-Index: linux-2.6.27.y/arch/Kconfig
-===================================================================
---- linux-2.6.27.y.orig/arch/Kconfig
-+++ linux-2.6.27.y/arch/Kconfig
-@@ -13,9 +13,18 @@ config OPROFILE
+diff -Nurb linux-2.6.27-590/arch/Kconfig linux-2.6.27-591/arch/Kconfig
+--- linux-2.6.27-590/arch/Kconfig 2010-02-01 19:42:05.000000000 -0500
++++ linux-2.6.27-591/arch/Kconfig 2010-02-01 19:42:30.000000000 -0500
+@@ -13,9 +13,18 @@
If unsure, say N.
config KPROBES
bool "Kprobes"
depends on KALLSYMS && MODULES
-Index: linux-2.6.27.y/arch/x86/kernel/asm-offsets_32.c
-===================================================================
---- linux-2.6.27.y.orig/arch/x86/kernel/asm-offsets_32.c
-+++ linux-2.6.27.y/arch/x86/kernel/asm-offsets_32.c
+diff -Nurb linux-2.6.27-590/arch/x86/kernel/asm-offsets_32.c linux-2.6.27-591/arch/x86/kernel/asm-offsets_32.c
+--- linux-2.6.27-590/arch/x86/kernel/asm-offsets_32.c 2008-10-09 18:13:53.000000000 -0400
++++ linux-2.6.27-591/arch/x86/kernel/asm-offsets_32.c 2010-02-01 19:42:30.000000000 -0500
@@ -9,6 +9,7 @@
#include <linux/signal.h>
#include <linux/personality.h>
void foo(void)
{
OFFSET(IA32_SIGCONTEXT_ax, sigcontext, ax);
-@@ -50,6 +62,16 @@ void foo(void)
+@@ -50,6 +62,16 @@
OFFSET(CPUINFO_x86_vendor_id, cpuinfo_x86, x86_vendor_id);
BLANK();
OFFSET(TI_task, thread_info, task);
OFFSET(TI_exec_domain, thread_info, exec_domain);
OFFSET(TI_flags, thread_info, flags);
-Index: linux-2.6.27.y/arch/x86/kernel/entry_32.S
-===================================================================
---- linux-2.6.27.y.orig/arch/x86/kernel/entry_32.S
-+++ linux-2.6.27.y/arch/x86/kernel/entry_32.S
-@@ -426,6 +426,33 @@ ENTRY(system_call)
+diff -Nurb linux-2.6.27-590/arch/x86/kernel/entry_32.S linux-2.6.27-591/arch/x86/kernel/entry_32.S
+--- linux-2.6.27-590/arch/x86/kernel/entry_32.S 2008-10-09 18:13:53.000000000 -0400
++++ linux-2.6.27-591/arch/x86/kernel/entry_32.S 2010-02-01 19:42:30.000000000 -0500
+@@ -426,6 +426,33 @@
cmpl $(nr_syscalls), %eax
jae syscall_badsys
syscall_call:
call *sys_call_table(,%eax,4)
movl %eax,PT_EAX(%esp) # store the return value
syscall_exit:
-Index: linux-2.6.27.y/arch/x86/mm/fault.c
-===================================================================
---- linux-2.6.27.y.orig/arch/x86/mm/fault.c
-+++ linux-2.6.27.y/arch/x86/mm/fault.c
-@@ -79,6 +79,15 @@ static inline int notify_page_fault(stru
+diff -Nurb linux-2.6.27-590/arch/x86/mm/fault.c linux-2.6.27-591/arch/x86/mm/fault.c
+--- linux-2.6.27-590/arch/x86/mm/fault.c 2010-02-01 19:42:05.000000000 -0500
++++ linux-2.6.27-591/arch/x86/mm/fault.c 2010-02-01 19:42:30.000000000 -0500
+@@ -79,6 +79,15 @@
#endif
}
/*
* X86_32
* Sometimes AMD Athlon/Opteron CPUs report invalid exceptions on prefetch.
-Index: linux-2.6.27.y/drivers/oprofile/cpu_buffer.c
-===================================================================
---- linux-2.6.27.y.orig/drivers/oprofile/cpu_buffer.c
-+++ linux-2.6.27.y/drivers/oprofile/cpu_buffer.c
+diff -Nurb linux-2.6.27-590/drivers/oprofile/cpu_buffer.c linux-2.6.27-591/drivers/oprofile/cpu_buffer.c
+--- linux-2.6.27-590/drivers/oprofile/cpu_buffer.c 2008-10-09 18:13:53.000000000 -0400
++++ linux-2.6.27-591/drivers/oprofile/cpu_buffer.c 2010-02-01 19:42:30.000000000 -0500
@@ -21,6 +21,7 @@
#include <linux/oprofile.h>
#include <linux/vmalloc.h>
#include "event_buffer.h"
#include "cpu_buffer.h"
-@@ -147,6 +148,17 @@ static void increment_head(struct oprofi
+@@ -147,6 +148,17 @@
b->head_pos = 0;
}
static inline void
add_sample(struct oprofile_cpu_buffer * cpu_buf,
unsigned long pc, unsigned long event)
-@@ -155,6 +167,7 @@ add_sample(struct oprofile_cpu_buffer *
+@@ -155,6 +167,7 @@
entry->eip = pc;
entry->event = event;
increment_head(cpu_buf);
}
static inline void
-@@ -250,8 +263,28 @@ void oprofile_add_sample(struct pt_regs
+@@ -250,8 +263,28 @@
{
int is_kernel = !user_mode(regs);
unsigned long pc = profile_pc(regs);
}
void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event)
-Index: linux-2.6.27.y/fs/bio.c
-===================================================================
---- linux-2.6.27.y.orig/fs/bio.c
-+++ linux-2.6.27.y/fs/bio.c
+diff -Nurb linux-2.6.27-590/fs/bio.c linux-2.6.27-591/fs/bio.c
+--- linux-2.6.27-590/fs/bio.c 2008-10-09 18:13:53.000000000 -0400
++++ linux-2.6.27-591/fs/bio.c 2010-02-01 19:42:30.000000000 -0500
@@ -27,6 +27,7 @@
#include <linux/workqueue.h>
#include <linux/blktrace_api.h>
static struct kmem_cache *bio_slab __read_mostly;
-@@ -44,6 +45,7 @@ static struct biovec_slab bvec_slabs[BIO
+@@ -44,6 +45,7 @@
};
#undef BV
/*
* fs_bio_set is the bio_set containing bio and iovec memory pools used by
* IO code that does not need private memory pools.
-@@ -1171,6 +1173,14 @@ void bio_check_pages_dirty(struct bio *b
+@@ -1171,6 +1173,14 @@
}
}
/**
* bio_endio - end I/O on a bio
* @bio: bio
-@@ -1192,6 +1202,24 @@ void bio_endio(struct bio *bio, int erro
+@@ -1192,6 +1202,24 @@
else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
error = -EIO;
if (bio->bi_end_io)
bio->bi_end_io(bio, error);
}
-Index: linux-2.6.27.y/fs/exec.c
-===================================================================
---- linux-2.6.27.y.orig/fs/exec.c
-+++ linux-2.6.27.y/fs/exec.c
+diff -Nurb linux-2.6.27-590/fs/exec.c linux-2.6.27-591/fs/exec.c
+--- linux-2.6.27-590/fs/exec.c 2010-02-01 19:42:07.000000000 -0500
++++ linux-2.6.27-591/fs/exec.c 2010-02-01 19:42:31.000000000 -0500
@@ -27,6 +27,7 @@
#include <linux/fdtable.h>
#include <linux/mm.h>
#include <linux/fcntl.h>
#include <linux/smp_lock.h>
#include <linux/swap.h>
-@@ -698,6 +699,13 @@ struct file *open_exec(const char *name)
+@@ -698,6 +699,13 @@
goto out;
}
return file;
out_path_put:
-Index: linux-2.6.27.y/include/linux/arrays.h
-===================================================================
---- /dev/null
-+++ linux-2.6.27.y/include/linux/arrays.h
+diff -Nurb linux-2.6.27-590/include/linux/arrays.h linux-2.6.27-591/include/linux/arrays.h
+--- linux-2.6.27-590/include/linux/arrays.h 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.27-591/include/linux/arrays.h 2010-02-01 19:42:31.000000000 -0500
@@ -0,0 +1,36 @@
+#ifndef __ARRAYS_H__
+#define __ARRAYS_H__
+ struct task_struct *task;
+};
+#endif
-Index: linux-2.6.27.y/include/linux/sched.h.rej
-===================================================================
---- /dev/null
-+++ linux-2.6.27.y/include/linux/sched.h.rej
+diff -Nurb linux-2.6.27-590/include/linux/sched.h linux-2.6.27-591/include/linux/sched.h
+--- linux-2.6.27-590/include/linux/sched.h 2010-02-01 19:42:07.000000000 -0500
++++ linux-2.6.27-591/include/linux/sched.h 2010-02-01 19:47:30.000000000 -0500
+@@ -1133,6 +1133,11 @@
+ cputime_t utime, stime, utimescaled, stimescaled;
+ cputime_t gtime;
+ cputime_t prev_utime, prev_stime;
++
++ #ifdef CONFIG_CHOPSTIX
++ unsigned long last_interrupted, last_ran_j;
++ #endif
++
+ unsigned long nvcsw, nivcsw; /* context switch counts */
+ struct timespec start_time; /* monotonic time */
+ struct timespec real_start_time; /* boot based time */
+diff -Nurb linux-2.6.27-590/include/linux/sched.h.rej linux-2.6.27-591/include/linux/sched.h.rej
+--- linux-2.6.27-590/include/linux/sched.h.rej 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.27-591/include/linux/sched.h.rej 2010-02-01 19:42:31.000000000 -0500
@@ -0,0 +1,19 @@
+***************
+*** 850,855 ****
+ unsigned long long sched_time; /* sched_clock time spent running */
+ enum sleep_type sleep_type;
+
-Index: linux-2.6.27.y/kernel/sched.c
-===================================================================
---- linux-2.6.27.y.orig/kernel/sched.c
-+++ linux-2.6.27.y/kernel/sched.c
+diff -Nurb linux-2.6.27-590/kernel/sched.c linux-2.6.27-591/kernel/sched.c
+--- linux-2.6.27-590/kernel/sched.c 2010-02-01 19:42:07.000000000 -0500
++++ linux-2.6.27-591/kernel/sched.c 2010-02-01 19:47:30.000000000 -0500
@@ -10,7 +10,7 @@
* 1998-11-19 Implemented schedule_timeout() and related stuff
* by Andrea Arcangeli
/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
-@@ -4436,6 +4440,29 @@ pick_next_task(struct rq *rq, struct tas
+@@ -2368,6 +2372,10 @@
+ INIT_HLIST_HEAD(&p->preempt_notifiers);
+ #endif
+
++#ifdef CONFIG_CHOPSTIX
++ p->last_ran_j = jiffies;
++ p->last_interrupted = INTERRUPTIBLE;
++#endif
+ /*
+ * We mark the process as running here, but have not actually
+ * inserted it onto the runqueue yet. This guarantees that
+@@ -4428,6 +4436,29 @@
}
}
/*
* schedule() is the main scheduler function.
*/
-@@ -5382,6 +5409,7 @@ long sched_setaffinity(pid_t pid, const
+@@ -4482,6 +4513,61 @@
+ next = pick_next_task(rq, prev);
+
+ if (likely(prev != next)) {
++
++#ifdef CONFIG_CHOPSTIX
++ /* Run only if the Chopstix module so decrees it */
++ if (rec_event) {
++ unsigned long diff;
++ int sampling_reason;
++ prev->last_ran_j = jiffies;
++ if (next->last_interrupted!=INTERRUPTIBLE) {
++ if (next->last_interrupted!=RUNNING) {
++ diff = (jiffies-next->last_interrupted);
++ sampling_reason = 0;/* BLOCKING */
++ }
++ else {
++ diff = jiffies-next->last_ran_j;
++ sampling_reason = 1;/* PREEMPTION */
++ }
++
++ if (diff >= HZ/10) {
++ struct event_spec {
++ unsigned long pc;
++ unsigned long dcookie;
++ unsigned int count;
++ unsigned int reason;
++ };
++
++ struct event event;
++ struct event_spec espec;
++ struct pt_regs *regs;
++ regs = task_pt_regs(current);
++
++ espec.reason = sampling_reason;
++ event.event_data=&espec;
++ event.task=next;
++ espec.pc=regs->ip;
++ event.event_type=2;
++ /* index in the event array currently set up */
++ /* make sure the counters are loaded in the order we want them to show up*/
++ (*rec_event)(&event, diff);
++ }
++ }
++ /* next has been elected to run */
++ next->last_interrupted=0;
++
++ /* An uninterruptible process just yielded. Record the current jiffy */
++ if (prev->state & TASK_UNINTERRUPTIBLE) {
++ prev->last_interrupted=jiffies;
++ }
++ /* An interruptible process just yielded, or it got preempted.
++ * Mark it as interruptible */
++ else if (prev->state & TASK_INTERRUPTIBLE) {
++ prev->last_interrupted=INTERRUPTIBLE;
++ }
++ }
++#endif
++
+ sched_info_switch(prev, next);
+
+ rq->nr_switches++;
+@@ -5369,6 +5455,7 @@
get_task_struct(p);
read_unlock(&tasklist_lock);
retval = -EPERM;
if ((current->euid != p->euid) && (current->euid != p->uid) &&
!capable(CAP_SYS_NICE))
-Index: linux-2.6.27.y/kernel/sched.c.rej
-===================================================================
---- /dev/null
-+++ linux-2.6.27.y/kernel/sched.c.rej
-@@ -0,0 +1,258 @@
-+***************
-+*** 23,28 ****
-+ #include <linux/nmi.h>
-+ #include <linux/init.h>
-+ #include <asm/uaccess.h>
-+ #include <linux/highmem.h>
-+ #include <linux/smp_lock.h>
-+ #include <asm/mmu_context.h>
-+--- 23,29 ----
-+ #include <linux/nmi.h>
-+ #include <linux/init.h>
-+ #include <asm/uaccess.h>
-++ #include <linux/arrays.h>
-+ #include <linux/highmem.h>
-+ #include <linux/smp_lock.h>
-+ #include <asm/mmu_context.h>
-+***************
-+*** 451,456 ****
-+
-+ repeat_lock_task:
-+ rq = task_rq(p);
-+ spin_lock(&rq->lock);
-+ if (unlikely(rq != task_rq(p))) {
-+ spin_unlock(&rq->lock);
-+--- 455,461 ----
-+
-+ repeat_lock_task:
-+ rq = task_rq(p);
-++
-+ spin_lock(&rq->lock);
-+ if (unlikely(rq != task_rq(p))) {
-+ spin_unlock(&rq->lock);
-+***************
-+*** 1761,1766 ****
-+ * event cannot wake it up and insert it on the runqueue either.
-+ */
-+ p->state = TASK_RUNNING;
-+
-+ /*
-+ * Make sure we do not leak PI boosting priority to the child:
-+--- 1766,1786 ----
-+ * event cannot wake it up and insert it on the runqueue either.
-+ */
-+ p->state = TASK_RUNNING;
-++ #ifdef CONFIG_CHOPSTIX
-++ /* The jiffy of last interruption */
-++ if (p->state & TASK_UNINTERRUPTIBLE) {
-++ p->last_interrupted=jiffies;
-++ }
-++ else
-++ if (p->state & TASK_INTERRUPTIBLE) {
-++ p->last_interrupted=INTERRUPTIBLE;
-++ }
-++ else
-++ p->last_interrupted=RUNNING;
-++
-++ /* The jiffy of last execution */
-++ p->last_ran_j=jiffies;
-++ #endif
-+
-+ /*
-+ * Make sure we do not leak PI boosting priority to the child:
-+***************
-+*** 3628,3633 ****
-+
-+ #endif
-+
-+ static inline int interactive_sleep(enum sleep_type sleep_type)
-+ {
-+ return (sleep_type == SLEEP_INTERACTIVE ||
-+--- 3648,3654 ----
-+
-+ #endif
-+
-++
-+ static inline int interactive_sleep(enum sleep_type sleep_type)
-+ {
-+ return (sleep_type == SLEEP_INTERACTIVE ||
-+***************
-+*** 3637,3652 ****
-+ /*
-+ * schedule() is the main scheduler function.
-+ */
-+ asmlinkage void __sched schedule(void)
-+ {
-+ struct task_struct *prev, *next;
-+ struct prio_array *array;
-+ struct list_head *queue;
-+ unsigned long long now;
-+- unsigned long run_time;
-+ int cpu, idx, new_prio;
-+ long *switch_count;
-+ struct rq *rq;
-+
-+ /*
-+ * Test if we are atomic. Since do_exit() needs to call into
-+--- 3658,3685 ----
-+ /*
-+ * schedule() is the main scheduler function.
-+ */
-++
-++ #ifdef CONFIG_CHOPSTIX
-++ extern void (*rec_event)(void *,unsigned int);
-++ struct event_spec {
-++ unsigned long pc;
-++ unsigned long dcookie;
-++ unsigned int count;
-++ unsigned int reason;
-++ };
-++ #endif
-++
-+ asmlinkage void __sched schedule(void)
-+ {
-+ struct task_struct *prev, *next;
-+ struct prio_array *array;
-+ struct list_head *queue;
-+ unsigned long long now;
-++ unsigned long run_time, diff;
-+ int cpu, idx, new_prio;
-+ long *switch_count;
-+ struct rq *rq;
-++ int sampling_reason;
-+
-+ /*
-+ * Test if we are atomic. Since do_exit() needs to call into
-+***************
-+*** 3700,3705 ****
-+ switch_count = &prev->nivcsw;
-+ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
-+ switch_count = &prev->nvcsw;
-+ if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
-+ unlikely(signal_pending(prev))))
-+ prev->state = TASK_RUNNING;
-+--- 3733,3739 ----
-+ switch_count = &prev->nivcsw;
-+ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
-+ switch_count = &prev->nvcsw;
-++
-+ if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
-+ unlikely(signal_pending(prev))))
-+ prev->state = TASK_RUNNING;
-+***************
-+*** 3709,3714 ****
-+ vx_uninterruptible_inc(prev);
-+ }
-+ deactivate_task(prev, rq);
-+ }
-+ }
-+
-+--- 3743,3759 ----
-+ vx_uninterruptible_inc(prev);
-+ }
-+ deactivate_task(prev, rq);
-++ #ifdef CONFIG_CHOPSTIX
-++ /* An uninterruptible process just yielded. Record the current jiffie */
-++ if (prev->state & TASK_UNINTERRUPTIBLE) {
-++ prev->last_interrupted=jiffies;
-++ }
-++ /* An interruptible process just yielded, or it got preempted.
-++ * Mark it as interruptible */
-++ else if (prev->state & TASK_INTERRUPTIBLE) {
-++ prev->last_interrupted=INTERRUPTIBLE;
-++ }
-++ #endif
-+ }
-+ }
-+
-+***************
-+*** 3785,3790 ****
-+ prev->sleep_avg = 0;
-+ prev->timestamp = prev->last_ran = now;
-+
-+ sched_info_switch(prev, next);
-+ if (likely(prev != next)) {
-+ next->timestamp = next->last_ran = now;
-+--- 3830,3869 ----
-+ prev->sleep_avg = 0;
-+ prev->timestamp = prev->last_ran = now;
-+
-++ #ifdef CONFIG_CHOPSTIX
-++ /* Run only if the Chopstix module so decrees it */
-++ if (rec_event) {
-++ prev->last_ran_j = jiffies;
-++ if (next->last_interrupted!=INTERRUPTIBLE) {
-++ if (next->last_interrupted!=RUNNING) {
-++ diff = (jiffies-next->last_interrupted);
-++ sampling_reason = 0;/* BLOCKING */
-++ }
-++ else {
-++ diff = jiffies-next->last_ran_j;
-++ sampling_reason = 1;/* PREEMPTION */
-++ }
-++
-++ if (diff >= HZ/10) {
-++ struct event event;
-++ struct event_spec espec;
-++ struct pt_regs *regs;
-++ regs = task_pt_regs(current);
-++
-++ espec.reason = sampling_reason;
-++ event.event_data=&espec;
-++ event.task=next;
-++ espec.pc=regs->eip;
-++ event.event_type=2;
-++ /* index in the event array currently set up */
-++ /* make sure the counters are loaded in the order we want them to show up*/
-++ (*rec_event)(&event, diff);
-++ }
-++ }
-++ /* next has been elected to run */
-++ next->last_interrupted=0;
-++ }
-++ #endif
-+ sched_info_switch(prev, next);
-+ if (likely(prev != next)) {
-+ next->timestamp = next->last_ran = now;
-+***************
-+*** 5737,5742 ****
-+ jiffies_to_timespec(p->policy == SCHED_FIFO ?
-+ 0 : task_timeslice(p), &t);
-+ read_unlock(&tasklist_lock);
-+ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
-+ out_nounlock:
-+ return retval;
-+--- 5817,5823 ----
-+ jiffies_to_timespec(p->policy == SCHED_FIFO ?
-+ 0 : task_timeslice(p), &t);
-+ read_unlock(&tasklist_lock);
-++
-+ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
-+ out_nounlock:
-+ return retval;
-+***************
-+*** 7980,7982 ****
-+ }
-+
-+ #endif
-+--- 8061,8080 ----
-+ }
-+
-+ #endif
-++
-++ #ifdef CONFIG_CHOPSTIX
-++ void (*rec_event)(void *,unsigned int) = NULL;
-++
-++ /* To support safe calling from asm */
-++ asmlinkage void rec_event_asm (struct event *event_signature_in, unsigned int count) {
-++ struct pt_regs *regs;
-++ struct event_spec *es = event_signature_in->event_data;
-++ regs = task_pt_regs(current);
-++ event_signature_in->task=current;
-++ es->pc=regs->eip;
-++ event_signature_in->count=1;
-++ (*rec_event)(event_signature_in, count);
-++ }
-++ EXPORT_SYMBOL(rec_event);
-++ EXPORT_SYMBOL(in_sched_functions);
-++ #endif
-Index: linux-2.6.27.y/mm/memory.c
-===================================================================
---- linux-2.6.27.y.orig/mm/memory.c
-+++ linux-2.6.27.y/mm/memory.c
-@@ -61,6 +61,7 @@
-
- #include <linux/swapops.h>
- #include <linux/elf.h>
+diff -Nurb linux-2.6.27-590/kernel/sched.c.orig linux-2.6.27-591/kernel/sched.c.orig
+--- linux-2.6.27-590/kernel/sched.c.orig 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.27-591/kernel/sched.c.orig 2010-02-01 19:43:07.000000000 -0500
+@@ -0,0 +1,9326 @@
++/*
++ * kernel/sched.c
++ *
++ * Kernel scheduler and related syscalls
++ *
++ * Copyright (C) 1991-2002 Linus Torvalds
++ *
++ * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and
++ * make semaphores SMP safe
++ * 1998-11-19 Implemented schedule_timeout() and related stuff
++ * by Andrea Arcangeli
++ * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar:
++ * hybrid priority-list and round-robin deventn with
++ * an array-switch method of distributing timeslices
++ * and per-CPU runqueues. Cleanups and useful suggestions
++ * by Davide Libenzi, preemptible kernel bits by Robert Love.
++ * 2003-09-03 Interactivity tuning by Con Kolivas.
++ * 2004-04-02 Scheduler domains code by Nick Piggin
++ * 2007-04-15 Work begun on replacing all interactivity tuning with a
++ * fair scheduling design by Con Kolivas.
++ * 2007-05-05 Load balancing (smp-nice) and other improvements
++ * by Peter Williams
++ * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith
++ * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri
++ * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins,
++ * Thomas Gleixner, Mike Kravetz
++ */
++
++#include <linux/mm.h>
++#include <linux/module.h>
++#include <linux/nmi.h>
++#include <linux/init.h>
++#include <linux/uaccess.h>
++#include <linux/highmem.h>
++#include <linux/smp_lock.h>
++#include <asm/mmu_context.h>
++#include <linux/interrupt.h>
++#include <linux/capability.h>
++#include <linux/completion.h>
++#include <linux/kernel_stat.h>
++#include <linux/debug_locks.h>
++#include <linux/security.h>
++#include <linux/notifier.h>
++#include <linux/profile.h>
++#include <linux/freezer.h>
++#include <linux/vmalloc.h>
++#include <linux/blkdev.h>
++#include <linux/delay.h>
++#include <linux/pid_namespace.h>
++#include <linux/smp.h>
++#include <linux/threads.h>
++#include <linux/timer.h>
++#include <linux/rcupdate.h>
++#include <linux/cpu.h>
++#include <linux/cpuset.h>
++#include <linux/percpu.h>
++#include <linux/kthread.h>
++#include <linux/seq_file.h>
++#include <linux/sysctl.h>
++#include <linux/syscalls.h>
++#include <linux/times.h>
++#include <linux/tsacct_kern.h>
++#include <linux/kprobes.h>
++#include <linux/delayacct.h>
++#include <linux/reciprocal_div.h>
++#include <linux/unistd.h>
++#include <linux/pagemap.h>
++#include <linux/hrtimer.h>
++#include <linux/tick.h>
++#include <linux/bootmem.h>
++#include <linux/debugfs.h>
++#include <linux/ctype.h>
++#include <linux/ftrace.h>
++#include <linux/vs_sched.h>
++#include <linux/vs_cvirt.h>
+#include <linux/arrays.h>
-
- #include "internal.h"
-
-@@ -2753,6 +2754,15 @@ out:
- return ret;
- }
-
-+extern void (*rec_event)(void *,unsigned int);
-+struct event_spec {
-+ unsigned long pc;
-+ unsigned long dcookie;
-+ unsigned count;
-+ unsigned char reason;
++
++#include <asm/tlb.h>
++#include <asm/irq_regs.h>
++
++#include "sched_cpupri.h"
++
++#define INTERRUPTIBLE -1
++#define RUNNING 0
++
++/*
++ * Convert user-nice values [ -20 ... 0 ... 19 ]
++ * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
++ * and back.
++ */
++#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20)
++#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20)
++#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio)
++
++/*
++ * 'User priority' is the nice value converted to something we
++ * can work with better when scaling various scheduler parameters,
++ * it's a [ 0 ... 39 ] range.
++ */
++#define USER_PRIO(p) ((p)-MAX_RT_PRIO)
++#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
++#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
++
++/*
++ * Helpers for converting nanosecond timing to jiffy resolution
++ */
++#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
++
++#define NICE_0_LOAD SCHED_LOAD_SCALE
++#define NICE_0_SHIFT SCHED_LOAD_SHIFT
++
++/*
++ * These are the 'tuning knobs' of the scheduler:
++ *
++ * default timeslice is 100 msecs (used only for SCHED_RR tasks).
++ * Timeslices get refilled after they expire.
++ */
++#define DEF_TIMESLICE (100 * HZ / 1000)
++
++/*
++ * single value that denotes runtime == period, ie unlimited time.
++ */
++#define RUNTIME_INF ((u64)~0ULL)
++
++#ifdef CONFIG_SMP
++/*
++ * Divide a load by a sched group cpu_power : (load / sg->__cpu_power)
++ * Since cpu_power is a 'constant', we can use a reciprocal divide.
++ */
++static inline u32 sg_div_cpu_power(const struct sched_group *sg, u32 load)
++{
++ return reciprocal_divide(load, sg->reciprocal_cpu_power);
++}
++
++/*
++ * Each time a sched group cpu_power is changed,
++ * we must compute its reciprocal value
++ */
++static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val)
++{
++ sg->__cpu_power += val;
++ sg->reciprocal_cpu_power = reciprocal_value(sg->__cpu_power);
++}
++#endif
++
++static inline int rt_policy(int policy)
++{
++ if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
++ return 1;
++ return 0;
++}
++
++static inline int task_has_rt_policy(struct task_struct *p)
++{
++ return rt_policy(p->policy);
++}
++
++/*
++ * This is the priority-queue data structure of the RT scheduling class:
++ */
++struct rt_prio_array {
++ DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
++ struct list_head queue[MAX_RT_PRIO];
+};
+
++struct rt_bandwidth {
++ /* nests inside the rq lock: */
++ spinlock_t rt_runtime_lock;
++ ktime_t rt_period;
++ u64 rt_runtime;
++ struct hrtimer rt_period_timer;
++};
+
- /*
- * By the time we get here, we already hold the mm semaphore
- */
-@@ -2782,6 +2792,24 @@ int handle_mm_fault(struct mm_struct *mm
- if (!pte)
- return VM_FAULT_OOM;
-
-+#ifdef CONFIG_CHOPSTIX
-+ if (rec_event) {
-+ struct event event;
-+ struct event_spec espec;
-+ struct pt_regs *regs;
-+ unsigned int pc;
-+ regs = task_pt_regs(current);
-+ pc = regs->ip & (unsigned int) ~4095;
++static struct rt_bandwidth def_rt_bandwidth;
+
-+ espec.reason = 0; /* alloc */
-+ event.event_data=&espec;
-+ event.task = current;
-+ espec.pc=pc;
-+ event.event_type=5;
-+ (*rec_event)(&event, 1);
++static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
++
++static enum hrtimer_restart sched_rt_period_timer(struct hrtimer *timer)
++{
++ struct rt_bandwidth *rt_b =
++ container_of(timer, struct rt_bandwidth, rt_period_timer);
++ ktime_t now;
++ int overrun;
++ int idle = 0;
++
++ for (;;) {
++ now = hrtimer_cb_get_time(timer);
++ overrun = hrtimer_forward(timer, now, rt_b->rt_period);
++
++ if (!overrun)
++ break;
++
++ idle = do_sched_rt_period_timer(rt_b, overrun);
++ }
++
++ return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
++}
++
++static
++void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
++{
++ rt_b->rt_period = ns_to_ktime(period);
++ rt_b->rt_runtime = runtime;
++
++ spin_lock_init(&rt_b->rt_runtime_lock);
++
++ hrtimer_init(&rt_b->rt_period_timer,
++ CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++ rt_b->rt_period_timer.function = sched_rt_period_timer;
++ rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED;
++}
++
++static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
++{
++ ktime_t now;
++
++ if (rt_b->rt_runtime == RUNTIME_INF)
++ return;
++
++ if (hrtimer_active(&rt_b->rt_period_timer))
++ return;
++
++ spin_lock(&rt_b->rt_runtime_lock);
++ for (;;) {
++ if (hrtimer_active(&rt_b->rt_period_timer))
++ break;
++
++ now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
++ hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
++ hrtimer_start(&rt_b->rt_period_timer,
++ rt_b->rt_period_timer.expires,
++ HRTIMER_MODE_ABS);
+ }
++ spin_unlock(&rt_b->rt_runtime_lock);
++}
++
++#ifdef CONFIG_RT_GROUP_SCHED
++static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
++{
++ hrtimer_cancel(&rt_b->rt_period_timer);
++}
+#endif
+
- return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
- }
-
-Index: linux-2.6.27.y/mm/slab.c
-===================================================================
---- linux-2.6.27.y.orig/mm/slab.c
-+++ linux-2.6.27.y/mm/slab.c
++/*
++ * sched_domains_mutex serializes calls to arch_init_sched_domains,
++ * detach_destroy_domains and partition_sched_domains.
++ */
++static DEFINE_MUTEX(sched_domains_mutex);
++
++#ifdef CONFIG_GROUP_SCHED
++
++#include <linux/cgroup.h>
++
++struct cfs_rq;
++
++static LIST_HEAD(task_groups);
++
++/* task group related information */
++struct task_group {
++#ifdef CONFIG_CGROUP_SCHED
++ struct cgroup_subsys_state css;
++#endif
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ /* schedulable entities of this group on each cpu */
++ struct sched_entity **se;
++ /* runqueue "owned" by this group on each cpu */
++ struct cfs_rq **cfs_rq;
++ unsigned long shares;
++#endif
++
++#ifdef CONFIG_RT_GROUP_SCHED
++ struct sched_rt_entity **rt_se;
++ struct rt_rq **rt_rq;
++
++ struct rt_bandwidth rt_bandwidth;
++#endif
++
++ struct rcu_head rcu;
++ struct list_head list;
++
++ struct task_group *parent;
++ struct list_head siblings;
++ struct list_head children;
++};
++
++#ifdef CONFIG_USER_SCHED
++
++/*
++ * Root task group.
++ * Every UID task group (including init_task_group aka UID-0) will
++ * be a child to this group.
++ */
++struct task_group root_task_group;
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++/* Default task group's sched entity on each cpu */
++static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
++/* Default task group's cfs_rq on each cpu */
++static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++
++#ifdef CONFIG_RT_GROUP_SCHED
++static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
++static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
++#endif /* CONFIG_RT_GROUP_SCHED */
++#else /* !CONFIG_FAIR_GROUP_SCHED */
++#define root_task_group init_task_group
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++
++/* task_group_lock serializes add/remove of task groups and also changes to
++ * a task group's cpu shares.
++ */
++static DEFINE_SPINLOCK(task_group_lock);
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++#ifdef CONFIG_USER_SCHED
++# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
++#else /* !CONFIG_USER_SCHED */
++# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
++#endif /* CONFIG_USER_SCHED */
++
++/*
++ * A weight of 0 or 1 can cause arithmetics problems.
++ * A weight of a cfs_rq is the sum of weights of which entities
++ * are queued on this cfs_rq, so a weight of a entity should not be
++ * too large, so as the shares value of a task group.
++ * (The default weight is 1024 - so there's no practical
++ * limitation from this.)
++ */
++#define MIN_SHARES 2
++#define MAX_SHARES (1UL << 18)
++
++static int init_task_group_load = INIT_TASK_GROUP_LOAD;
++#endif
++
++/* Default task group.
++ * Every task in system belong to this group at bootup.
++ */
++struct task_group init_task_group;
++
++/* return group to which a task belongs */
++static inline struct task_group *task_group(struct task_struct *p)
++{
++ struct task_group *tg;
++
++#ifdef CONFIG_USER_SCHED
++ tg = p->user->tg;
++#elif defined(CONFIG_CGROUP_SCHED)
++ tg = container_of(task_subsys_state(p, cpu_cgroup_subsys_id),
++ struct task_group, css);
++#else
++ tg = &init_task_group;
++#endif
++ return tg;
++}
++
++/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
++static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
++{
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
++ p->se.parent = task_group(p)->se[cpu];
++#endif
++
++#ifdef CONFIG_RT_GROUP_SCHED
++ p->rt.rt_rq = task_group(p)->rt_rq[cpu];
++ p->rt.parent = task_group(p)->rt_se[cpu];
++#endif
++}
++
++#else
++
++static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
++static inline struct task_group *task_group(struct task_struct *p)
++{
++ return NULL;
++}
++
++#endif /* CONFIG_GROUP_SCHED */
++
++/* CFS-related fields in a runqueue */
++struct cfs_rq {
++ struct load_weight load;
++ unsigned long nr_running;
++
++ u64 exec_clock;
++ u64 min_vruntime;
++ u64 pair_start;
++
++ struct rb_root tasks_timeline;
++ struct rb_node *rb_leftmost;
++
++ struct list_head tasks;
++ struct list_head *balance_iterator;
++
++ /*
++ * 'curr' points to currently running entity on this cfs_rq.
++ * It is set to NULL otherwise (i.e when none are currently running).
++ */
++ struct sched_entity *curr, *next;
++
++ unsigned long nr_spread_over;
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
++
++ /*
++ * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
++ * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
++ * (like users, containers etc.)
++ *
++ * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
++ * list is used during load balance.
++ */
++ struct list_head leaf_cfs_rq_list;
++ struct task_group *tg; /* group that "owns" this runqueue */
++
++#ifdef CONFIG_SMP
++ /*
++ * the part of load.weight contributed by tasks
++ */
++ unsigned long task_weight;
++
++ /*
++ * h_load = weight * f(tg)
++ *
++ * Where f(tg) is the recursive weight fraction assigned to
++ * this group.
++ */
++ unsigned long h_load;
++
++ /*
++ * this cpu's part of tg->shares
++ */
++ unsigned long shares;
++
++ /*
++ * load.weight at the time we set shares
++ */
++ unsigned long rq_weight;
++#endif
++#endif
++};
++
++/* Real-Time classes' related field in a runqueue: */
++struct rt_rq {
++ struct rt_prio_array active;
++ unsigned long rt_nr_running;
++#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
++ int highest_prio; /* highest queued rt task prio */
++#endif
++#ifdef CONFIG_SMP
++ unsigned long rt_nr_migratory;
++ int overloaded;
++#endif
++ int rt_throttled;
++ u64 rt_time;
++ u64 rt_runtime;
++ /* Nests inside the rq lock: */
++ spinlock_t rt_runtime_lock;
++
++#ifdef CONFIG_RT_GROUP_SCHED
++ unsigned long rt_nr_boosted;
++
++ struct rq *rq;
++ struct list_head leaf_rt_rq_list;
++ struct task_group *tg;
++ struct sched_rt_entity *rt_se;
++#endif
++};
++
++#ifdef CONFIG_SMP
++
++/*
++ * We add the notion of a root-domain which will be used to define per-domain
++ * variables. Each exclusive cpuset essentially defines an island domain by
++ * fully partitioning the member cpus from any other cpuset. Whenever a new
++ * exclusive cpuset is created, we also create and attach a new root-domain
++ * object.
++ *
++ */
++struct root_domain {
++ atomic_t refcount;
++ cpumask_t span;
++ cpumask_t online;
++
++ /*
++ * The "RT overload" flag: it gets set if a CPU has more than
++ * one runnable RT task.
++ */
++ cpumask_t rto_mask;
++ atomic_t rto_count;
++#ifdef CONFIG_SMP
++ struct cpupri cpupri;
++#endif
++};
++
++/*
++ * By default the system creates a single root-domain with all cpus as
++ * members (mimicking the global state we have today).
++ */
++static struct root_domain def_root_domain;
++
++#endif
++ unsigned long norm_time;
++ unsigned long idle_time;
++#ifdef CONFIG_VSERVER_IDLETIME
++ int idle_skip;
++#endif
++#ifdef CONFIG_VSERVER_HARDCPU
++ struct list_head hold_queue;
++ unsigned long nr_onhold;
++ int idle_tokens;
++#endif
++
++/*
++ * This is the main, per-CPU runqueue data structure.
++ *
++ * Locking rule: those places that want to lock multiple runqueues
++ * (such as the load balancing or the thread migration code), lock
++ * acquire operations must be ordered by ascending &runqueue.
++ */
++struct rq {
++ /* runqueue lock: */
++ spinlock_t lock;
++
++ /*
++ * nr_running and cpu_load should be in the same cacheline because
++ * remote CPUs use both these fields when doing load calculation.
++ */
++ unsigned long nr_running;
++ #define CPU_LOAD_IDX_MAX 5
++ unsigned long cpu_load[CPU_LOAD_IDX_MAX];
++ unsigned char idle_at_tick;
++#ifdef CONFIG_NO_HZ
++ unsigned long last_tick_seen;
++ unsigned char in_nohz_recently;
++#endif
++ /* capture load from *all* tasks on this cpu: */
++ struct load_weight load;
++ unsigned long nr_load_updates;
++ u64 nr_switches;
++
++ struct cfs_rq cfs;
++ struct rt_rq rt;
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ /* list of leaf cfs_rq on this cpu: */
++ struct list_head leaf_cfs_rq_list;
++#endif
++#ifdef CONFIG_RT_GROUP_SCHED
++ struct list_head leaf_rt_rq_list;
++#endif
++
++ /*
++ * This is part of a global counter where only the total sum
++ * over all CPUs matters. A task can increase this counter on
++ * one CPU and if it got migrated afterwards it may decrease
++ * it on another CPU. Always updated under the runqueue lock:
++ */
++ unsigned long nr_uninterruptible;
++
++ struct task_struct *curr, *idle;
++ unsigned long next_balance;
++ struct mm_struct *prev_mm;
++
++ u64 clock;
++
++ atomic_t nr_iowait;
++
++#ifdef CONFIG_SMP
++ struct root_domain *rd;
++ struct sched_domain *sd;
++
++ /* For active balancing */
++ int active_balance;
++ int push_cpu;
++ /* cpu of this runqueue: */
++ int cpu;
++ int online;
++
++ unsigned long avg_load_per_task;
++
++ struct task_struct *migration_thread;
++ struct list_head migration_queue;
++#endif
++
++#ifdef CONFIG_SCHED_HRTICK
++#ifdef CONFIG_SMP
++ int hrtick_csd_pending;
++ struct call_single_data hrtick_csd;
++#endif
++ struct hrtimer hrtick_timer;
++#endif
++
++#ifdef CONFIG_SCHEDSTATS
++ /* latency stats */
++ struct sched_info rq_sched_info;
++
++ /* sys_sched_yield() stats */
++ unsigned int yld_exp_empty;
++ unsigned int yld_act_empty;
++ unsigned int yld_both_empty;
++ unsigned int yld_count;
++
++ /* schedule() stats */
++ unsigned int sched_switch;
++ unsigned int sched_count;
++ unsigned int sched_goidle;
++
++ /* try_to_wake_up() stats */
++ unsigned int ttwu_count;
++ unsigned int ttwu_local;
++
++ /* BKL stats */
++ unsigned int bkl_count;
++#endif
++};
++
++static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
++
++static inline void check_preempt_curr(struct rq *rq, struct task_struct *p)
++{
++ rq->curr->sched_class->check_preempt_curr(rq, p);
++}
++
++static inline int cpu_of(struct rq *rq)
++{
++#ifdef CONFIG_SMP
++ return rq->cpu;
++#else
++ return 0;
++#endif
++}
++
++/*
++ * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
++ * See detach_destroy_domains: synchronize_sched for details.
++ *
++ * The domain tree of any CPU may only be accessed from within
++ * preempt-disabled sections.
++ */
++#define for_each_domain(cpu, __sd) \
++ for (__sd = rcu_dereference(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent)
++
++#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
++#define this_rq() (&__get_cpu_var(runqueues))
++#define task_rq(p) cpu_rq(task_cpu(p))
++#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
++
++static inline void update_rq_clock(struct rq *rq)
++{
++ rq->clock = sched_clock_cpu(cpu_of(rq));
++}
++
++/*
++ * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
++ */
++#ifdef CONFIG_SCHED_DEBUG
++# define const_debug __read_mostly
++#else
++# define const_debug static const
++#endif
++
++/**
++ * runqueue_is_locked
++ *
++ * Returns true if the current cpu runqueue is locked.
++ * This interface allows printk to be called with the runqueue lock
++ * held and know whether or not it is OK to wake up the klogd.
++ */
++int runqueue_is_locked(void)
++{
++ int cpu = get_cpu();
++ struct rq *rq = cpu_rq(cpu);
++ int ret;
++
++ ret = spin_is_locked(&rq->lock);
++ put_cpu();
++ return ret;
++}
++
++/*
++ * Debugging: various feature bits
++ */
++
++#define SCHED_FEAT(name, enabled) \
++ __SCHED_FEAT_##name ,
++
++enum {
++#include "sched_features.h"
++};
++
++#undef SCHED_FEAT
++
++#define SCHED_FEAT(name, enabled) \
++ (1UL << __SCHED_FEAT_##name) * enabled |
++
++const_debug unsigned int sysctl_sched_features =
++#include "sched_features.h"
++ 0;
++
++#undef SCHED_FEAT
++
++#ifdef CONFIG_SCHED_DEBUG
++#define SCHED_FEAT(name, enabled) \
++ #name ,
++
++static __read_mostly char *sched_feat_names[] = {
++#include "sched_features.h"
++ NULL
++};
++
++#undef SCHED_FEAT
++
++static int sched_feat_open(struct inode *inode, struct file *filp)
++{
++ filp->private_data = inode->i_private;
++ return 0;
++}
++
++static ssize_t
++sched_feat_read(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ char *buf;
++ int r = 0;
++ int len = 0;
++ int i;
++
++ for (i = 0; sched_feat_names[i]; i++) {
++ len += strlen(sched_feat_names[i]);
++ len += 4;
++ }
++
++ buf = kmalloc(len + 2, GFP_KERNEL);
++ if (!buf)
++ return -ENOMEM;
++
++ for (i = 0; sched_feat_names[i]; i++) {
++ if (sysctl_sched_features & (1UL << i))
++ r += sprintf(buf + r, "%s ", sched_feat_names[i]);
++ else
++ r += sprintf(buf + r, "NO_%s ", sched_feat_names[i]);
++ }
++
++ r += sprintf(buf + r, "\n");
++ WARN_ON(r >= len + 2);
++
++ r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++
++ kfree(buf);
++
++ return r;
++}
++
++static ssize_t
++sched_feat_write(struct file *filp, const char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ char buf[64];
++ char *cmp = buf;
++ int neg = 0;
++ int i;
++
++ if (cnt > 63)
++ cnt = 63;
++
++ if (copy_from_user(&buf, ubuf, cnt))
++ return -EFAULT;
++
++ buf[cnt] = 0;
++
++ if (strncmp(buf, "NO_", 3) == 0) {
++ neg = 1;
++ cmp += 3;
++ }
++
++ for (i = 0; sched_feat_names[i]; i++) {
++ int len = strlen(sched_feat_names[i]);
++
++ if (strncmp(cmp, sched_feat_names[i], len) == 0) {
++ if (neg)
++ sysctl_sched_features &= ~(1UL << i);
++ else
++ sysctl_sched_features |= (1UL << i);
++ break;
++ }
++ }
++
++ if (!sched_feat_names[i])
++ return -EINVAL;
++
++ filp->f_pos += cnt;
++
++ return cnt;
++}
++
++static struct file_operations sched_feat_fops = {
++ .open = sched_feat_open,
++ .read = sched_feat_read,
++ .write = sched_feat_write,
++};
++
++static __init int sched_init_debug(void)
++{
++ debugfs_create_file("sched_features", 0644, NULL, NULL,
++ &sched_feat_fops);
++
++ return 0;
++}
++late_initcall(sched_init_debug);
++
++#endif
++
++#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
++
++/*
++ * Number of tasks to iterate in a single balance run.
++ * Limited because this is done with IRQs disabled.
++ */
++const_debug unsigned int sysctl_sched_nr_migrate = 32;
++
++/*
++ * ratelimit for updating the group shares.
++ * default: 0.25ms
++ */
++unsigned int sysctl_sched_shares_ratelimit = 250000;
++
++/*
++ * period over which we measure -rt task cpu usage in us.
++ * default: 1s
++ */
++unsigned int sysctl_sched_rt_period = 1000000;
++
++static __read_mostly int scheduler_running;
++
++/*
++ * part of the period that we allow rt tasks to run in us.
++ * default: 0.95s
++ */
++int sysctl_sched_rt_runtime = 950000;
++
++static inline u64 global_rt_period(void)
++{
++ return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
++}
++
++static inline u64 global_rt_runtime(void)
++{
++ if (sysctl_sched_rt_runtime < 0)
++ return RUNTIME_INF;
++
++ return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
++}
++
++#ifndef prepare_arch_switch
++# define prepare_arch_switch(next) do { } while (0)
++#endif
++#ifndef finish_arch_switch
++# define finish_arch_switch(prev) do { } while (0)
++#endif
++
++static inline int task_current(struct rq *rq, struct task_struct *p)
++{
++ return rq->curr == p;
++}
++
++#ifndef __ARCH_WANT_UNLOCKED_CTXSW
++static inline int task_running(struct rq *rq, struct task_struct *p)
++{
++ return task_current(rq, p);
++}
++
++static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
++{
++}
++
++static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
++{
++#ifdef CONFIG_DEBUG_SPINLOCK
++ /* this is a valid case when another task releases the spinlock */
++ rq->lock.owner = current;
++#endif
++ /*
++ * If we are tracking spinlock dependencies then we have to
++ * fix up the runqueue lock - which gets 'carried over' from
++ * prev into current:
++ */
++ spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
++
++ spin_unlock_irq(&rq->lock);
++}
++
++#else /* __ARCH_WANT_UNLOCKED_CTXSW */
++static inline int task_running(struct rq *rq, struct task_struct *p)
++{
++#ifdef CONFIG_SMP
++ return p->oncpu;
++#else
++ return task_current(rq, p);
++#endif
++}
++
++static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
++{
++#ifdef CONFIG_SMP
++ /*
++ * We can optimise this out completely for !SMP, because the
++ * SMP rebalancing from interrupt is the only thing that cares
++ * here.
++ */
++ next->oncpu = 1;
++#endif
++#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ spin_unlock_irq(&rq->lock);
++#else
++ spin_unlock(&rq->lock);
++#endif
++}
++
++static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
++{
++#ifdef CONFIG_SMP
++ /*
++ * After ->oncpu is cleared, the task can be moved to a different CPU.
++ * We must ensure this doesn't happen until the switch is completely
++ * finished.
++ */
++ smp_wmb();
++ prev->oncpu = 0;
++#endif
++#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ local_irq_enable();
++#endif
++}
++#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
++
++/*
++ * __task_rq_lock - lock the runqueue a given task resides on.
++ * Must be called interrupts disabled.
++ */
++static inline struct rq *__task_rq_lock(struct task_struct *p)
++ __acquires(rq->lock)
++{
++ for (;;) {
++ struct rq *rq = task_rq(p);
++ spin_lock(&rq->lock);
++ if (likely(rq == task_rq(p)))
++ return rq;
++ spin_unlock(&rq->lock);
++ }
++}
++
++/*
++ * task_rq_lock - lock the runqueue a given task resides on and disable
++ * interrupts. Note the ordering: we can safely lookup the task_rq without
++ * explicitly disabling preemption.
++ */
++static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
++ __acquires(rq->lock)
++{
++ struct rq *rq;
++
++ for (;;) {
++ local_irq_save(*flags);
++ rq = task_rq(p);
++ spin_lock(&rq->lock);
++ if (likely(rq == task_rq(p)))
++ return rq;
++ spin_unlock_irqrestore(&rq->lock, *flags);
++ }
++}
++
++static void __task_rq_unlock(struct rq *rq)
++ __releases(rq->lock)
++{
++ spin_unlock(&rq->lock);
++}
++
++static inline void task_rq_unlock(struct rq *rq, unsigned long *flags)
++ __releases(rq->lock)
++{
++ spin_unlock_irqrestore(&rq->lock, *flags);
++}
++
++/*
++ * this_rq_lock - lock this runqueue and disable interrupts.
++ */
++static struct rq *this_rq_lock(void)
++ __acquires(rq->lock)
++{
++ struct rq *rq;
++
++ local_irq_disable();
++ rq = this_rq();
++ spin_lock(&rq->lock);
++
++ return rq;
++}
++
++#ifdef CONFIG_SCHED_HRTICK
++/*
++ * Use HR-timers to deliver accurate preemption points.
++ *
++ * Its all a bit involved since we cannot program an hrt while holding the
++ * rq->lock. So what we do is store a state in in rq->hrtick_* and ask for a
++ * reschedule event.
++ *
++ * When we get rescheduled we reprogram the hrtick_timer outside of the
++ * rq->lock.
++ */
++
++/*
++ * Use hrtick when:
++ * - enabled by features
++ * - hrtimer is actually high res
++ */
++static inline int hrtick_enabled(struct rq *rq)
++{
++ if (!sched_feat(HRTICK))
++ return 0;
++ if (!cpu_active(cpu_of(rq)))
++ return 0;
++ return hrtimer_is_hres_active(&rq->hrtick_timer);
++}
++
++static void hrtick_clear(struct rq *rq)
++{
++ if (hrtimer_active(&rq->hrtick_timer))
++ hrtimer_cancel(&rq->hrtick_timer);
++}
++
++/*
++ * High-resolution timer tick.
++ * Runs from hardirq context with interrupts disabled.
++ */
++static enum hrtimer_restart hrtick(struct hrtimer *timer)
++{
++ struct rq *rq = container_of(timer, struct rq, hrtick_timer);
++
++ WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
++
++ spin_lock(&rq->lock);
++ update_rq_clock(rq);
++ rq->curr->sched_class->task_tick(rq, rq->curr, 1);
++ spin_unlock(&rq->lock);
++
++ return HRTIMER_NORESTART;
++}
++
++#ifdef CONFIG_SMP
++/*
++ * called from hardirq (IPI) context
++ */
++static void __hrtick_start(void *arg)
++{
++ struct rq *rq = arg;
++
++ spin_lock(&rq->lock);
++ hrtimer_restart(&rq->hrtick_timer);
++ rq->hrtick_csd_pending = 0;
++ spin_unlock(&rq->lock);
++}
++
++/*
++ * Called to set the hrtick timer state.
++ *
++ * called with rq->lock held and irqs disabled
++ */
++static void hrtick_start(struct rq *rq, u64 delay)
++{
++ struct hrtimer *timer = &rq->hrtick_timer;
++ ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
++
++ timer->expires = time;
++
++ if (rq == this_rq()) {
++ hrtimer_restart(timer);
++ } else if (!rq->hrtick_csd_pending) {
++ __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd);
++ rq->hrtick_csd_pending = 1;
++ }
++}
++
++static int
++hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
++{
++ int cpu = (int)(long)hcpu;
++
++ switch (action) {
++ case CPU_UP_CANCELED:
++ case CPU_UP_CANCELED_FROZEN:
++ case CPU_DOWN_PREPARE:
++ case CPU_DOWN_PREPARE_FROZEN:
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ hrtick_clear(cpu_rq(cpu));
++ return NOTIFY_OK;
++ }
++
++ return NOTIFY_DONE;
++}
++
++static __init void init_hrtick(void)
++{
++ hotcpu_notifier(hotplug_hrtick, 0);
++}
++#else
++/*
++ * Called to set the hrtick timer state.
++ *
++ * called with rq->lock held and irqs disabled
++ */
++static void hrtick_start(struct rq *rq, u64 delay)
++{
++ hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL);
++}
++
++static void init_hrtick(void)
++{
++}
++#endif /* CONFIG_SMP */
++
++static void init_rq_hrtick(struct rq *rq)
++{
++#ifdef CONFIG_SMP
++ rq->hrtick_csd_pending = 0;
++
++ rq->hrtick_csd.flags = 0;
++ rq->hrtick_csd.func = __hrtick_start;
++ rq->hrtick_csd.info = rq;
++#endif
++
++ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++ rq->hrtick_timer.function = hrtick;
++ rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
++}
++#else
++static inline void hrtick_clear(struct rq *rq)
++{
++}
++
++static inline void init_rq_hrtick(struct rq *rq)
++{
++}
++
++static inline void init_hrtick(void)
++{
++}
++#endif
++
++/*
++ * resched_task - mark a task 'to be rescheduled now'.
++ *
++ * On UP this means the setting of the need_resched flag, on SMP it
++ * might also involve a cross-CPU call to trigger the scheduler on
++ * the target CPU.
++ */
++#ifdef CONFIG_SMP
++
++#ifndef tsk_is_polling
++#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
++#endif
++
++static void resched_task(struct task_struct *p)
++{
++ int cpu;
++
++ assert_spin_locked(&task_rq(p)->lock);
++
++ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
++ return;
++
++ set_tsk_thread_flag(p, TIF_NEED_RESCHED);
++
++ cpu = task_cpu(p);
++ if (cpu == smp_processor_id())
++ return;
++
++ /* NEED_RESCHED must be visible before we test polling */
++ smp_mb();
++ if (!tsk_is_polling(p))
++ smp_send_reschedule(cpu);
++}
++
++static void resched_cpu(int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long flags;
++
++ if (!spin_trylock_irqsave(&rq->lock, flags))
++ return;
++ resched_task(cpu_curr(cpu));
++ spin_unlock_irqrestore(&rq->lock, flags);
++}
++
++#ifdef CONFIG_NO_HZ
++/*
++ * When add_timer_on() enqueues a timer into the timer wheel of an
++ * idle CPU then this timer might expire before the next timer event
++ * which is scheduled to wake up that CPU. In case of a completely
++ * idle system the next event might even be infinite time into the
++ * future. wake_up_idle_cpu() ensures that the CPU is woken up and
++ * leaves the inner idle loop so the newly added timer is taken into
++ * account when the CPU goes back to idle and evaluates the timer
++ * wheel for the next timer event.
++ */
++void wake_up_idle_cpu(int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++
++ if (cpu == smp_processor_id())
++ return;
++
++ /*
++ * This is safe, as this function is called with the timer
++ * wheel base lock of (cpu) held. When the CPU is on the way
++ * to idle and has not yet set rq->curr to idle then it will
++ * be serialized on the timer wheel base lock and take the new
++ * timer into account automatically.
++ */
++ if (rq->curr != rq->idle)
++ return;
++
++ /*
++ * We can set TIF_RESCHED on the idle task of the other CPU
++ * lockless. The worst case is that the other CPU runs the
++ * idle task through an additional NOOP schedule()
++ */
++ set_tsk_thread_flag(rq->idle, TIF_NEED_RESCHED);
++
++ /* NEED_RESCHED must be visible before we test polling */
++ smp_mb();
++ if (!tsk_is_polling(rq->idle))
++ smp_send_reschedule(cpu);
++}
++#endif /* CONFIG_NO_HZ */
++
++#else /* !CONFIG_SMP */
++static void resched_task(struct task_struct *p)
++{
++ assert_spin_locked(&task_rq(p)->lock);
++ set_tsk_need_resched(p);
++}
++#endif /* CONFIG_SMP */
++
++#if BITS_PER_LONG == 32
++# define WMULT_CONST (~0UL)
++#else
++# define WMULT_CONST (1UL << 32)
++#endif
++
++#define WMULT_SHIFT 32
++
++/*
++ * Shift right and round:
++ */
++#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
++
++/*
++ * delta *= weight / lw
++ */
++static unsigned long
++calc_delta_mine(unsigned long delta_exec, unsigned long weight,
++ struct load_weight *lw)
++{
++ u64 tmp;
++
++ if (!lw->inv_weight) {
++ if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST))
++ lw->inv_weight = 1;
++ else
++ lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)
++ / (lw->weight+1);
++ }
++
++ tmp = (u64)delta_exec * weight;
++ /*
++ * Check whether we'd overflow the 64-bit multiplication:
++ */
++ if (unlikely(tmp > WMULT_CONST))
++ tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
++ WMULT_SHIFT/2);
++ else
++ tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT);
++
++ return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
++}
++
++static inline void update_load_add(struct load_weight *lw, unsigned long inc)
++{
++ lw->weight += inc;
++ lw->inv_weight = 0;
++}
++
++static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
++{
++ lw->weight -= dec;
++ lw->inv_weight = 0;
++}
++
++/*
++ * To aid in avoiding the subversion of "niceness" due to uneven distribution
++ * of tasks with abnormal "nice" values across CPUs the contribution that
++ * each task makes to its run queue's load is weighted according to its
++ * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
++ * scaled version of the new time slice allocation that they receive on time
++ * slice expiry etc.
++ */
++
++#define WEIGHT_IDLEPRIO 2
++#define WMULT_IDLEPRIO (1 << 31)
++
++/*
++ * Nice levels are multiplicative, with a gentle 10% change for every
++ * nice level changed. I.e. when a CPU-bound task goes from nice 0 to
++ * nice 1, it will get ~10% less CPU time than another CPU-bound task
++ * that remained on nice 0.
++ *
++ * The "10% effect" is relative and cumulative: from _any_ nice level,
++ * if you go up 1 level, it's -10% CPU usage, if you go down 1 level
++ * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
++ * If a task goes up by ~10% and another task goes down by ~10% then
++ * the relative distance between them is ~25%.)
++ */
++static const int prio_to_weight[40] = {
++ /* -20 */ 88761, 71755, 56483, 46273, 36291,
++ /* -15 */ 29154, 23254, 18705, 14949, 11916,
++ /* -10 */ 9548, 7620, 6100, 4904, 3906,
++ /* -5 */ 3121, 2501, 1991, 1586, 1277,
++ /* 0 */ 1024, 820, 655, 526, 423,
++ /* 5 */ 335, 272, 215, 172, 137,
++ /* 10 */ 110, 87, 70, 56, 45,
++ /* 15 */ 36, 29, 23, 18, 15,
++};
++
++/*
++ * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
++ *
++ * In cases where the weight does not change often, we can use the
++ * precalculated inverse to speed up arithmetics by turning divisions
++ * into multiplications:
++ */
++static const u32 prio_to_wmult[40] = {
++ /* -20 */ 48388, 59856, 76040, 92818, 118348,
++ /* -15 */ 147320, 184698, 229616, 287308, 360437,
++ /* -10 */ 449829, 563644, 704093, 875809, 1099582,
++ /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326,
++ /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587,
++ /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126,
++ /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717,
++ /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
++};
++
++static void activate_task(struct rq *rq, struct task_struct *p, int wakeup);
++
++/*
++ * runqueue iterator, to support SMP load-balancing between different
++ * scheduling classes, without having to expose their internal data
++ * structures to the load-balancing proper:
++ */
++struct rq_iterator {
++ void *arg;
++ struct task_struct *(*start)(void *);
++ struct task_struct *(*next)(void *);
++};
++
++#ifdef CONFIG_SMP
++static unsigned long
++balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ unsigned long max_load_move, struct sched_domain *sd,
++ enum cpu_idle_type idle, int *all_pinned,
++ int *this_best_prio, struct rq_iterator *iterator);
++
++static int
++iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ struct sched_domain *sd, enum cpu_idle_type idle,
++ struct rq_iterator *iterator);
++#endif
++
++#ifdef CONFIG_CGROUP_CPUACCT
++static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
++#else
++static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
++#endif
++
++static inline void inc_cpu_load(struct rq *rq, unsigned long load)
++{
++ update_load_add(&rq->load, load);
++}
++
++static inline void dec_cpu_load(struct rq *rq, unsigned long load)
++{
++ update_load_sub(&rq->load, load);
++}
++
++#ifdef CONFIG_SMP
++static unsigned long source_load(int cpu, int type);
++static unsigned long target_load(int cpu, int type);
++static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
++
++static unsigned long cpu_avg_load_per_task(int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++
++ if (rq->nr_running)
++ rq->avg_load_per_task = rq->load.weight / rq->nr_running;
++
++ return rq->avg_load_per_task;
++}
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++
++typedef void (*tg_visitor)(struct task_group *, int, struct sched_domain *);
++
++/*
++ * Iterate the full tree, calling @down when first entering a node and @up when
++ * leaving it for the final time.
++ */
++static void
++walk_tg_tree(tg_visitor down, tg_visitor up, int cpu, struct sched_domain *sd)
++{
++ struct task_group *parent, *child;
++
++ rcu_read_lock();
++ parent = &root_task_group;
++down:
++ (*down)(parent, cpu, sd);
++ list_for_each_entry_rcu(child, &parent->children, siblings) {
++ parent = child;
++ goto down;
++
++up:
++ continue;
++ }
++ (*up)(parent, cpu, sd);
++
++ child = parent;
++ parent = parent->parent;
++ if (parent)
++ goto up;
++ rcu_read_unlock();
++}
++
++static void __set_se_shares(struct sched_entity *se, unsigned long shares);
++
++/*
++ * Calculate and set the cpu's group shares.
++ */
++static void
++__update_group_shares_cpu(struct task_group *tg, int cpu,
++ unsigned long sd_shares, unsigned long sd_rq_weight)
++{
++ int boost = 0;
++ unsigned long shares;
++ unsigned long rq_weight;
++
++ if (!tg->se[cpu])
++ return;
++
++ rq_weight = tg->cfs_rq[cpu]->load.weight;
++
++ /*
++ * If there are currently no tasks on the cpu pretend there is one of
++ * average load so that when a new task gets to run here it will not
++ * get delayed by group starvation.
++ */
++ if (!rq_weight) {
++ boost = 1;
++ rq_weight = NICE_0_LOAD;
++ }
++
++ if (unlikely(rq_weight > sd_rq_weight))
++ rq_weight = sd_rq_weight;
++
++ /*
++ * \Sum shares * rq_weight
++ * shares = -----------------------
++ * \Sum rq_weight
++ *
++ */
++ shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
++
++ /*
++ * record the actual number of shares, not the boosted amount.
++ */
++ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
++ tg->cfs_rq[cpu]->rq_weight = rq_weight;
++
++ if (shares < MIN_SHARES)
++ shares = MIN_SHARES;
++ else if (shares > MAX_SHARES)
++ shares = MAX_SHARES;
++
++ __set_se_shares(tg->se[cpu], shares);
++}
++
++/*
++ * Re-compute the task group their per cpu shares over the given domain.
++ * This needs to be done in a bottom-up fashion because the rq weight of a
++ * parent group depends on the shares of its child groups.
++ */
++static void
++tg_shares_up(struct task_group *tg, int cpu, struct sched_domain *sd)
++{
++ unsigned long rq_weight = 0;
++ unsigned long shares = 0;
++ int i;
++
++ for_each_cpu_mask(i, sd->span) {
++ rq_weight += tg->cfs_rq[i]->load.weight;
++ shares += tg->cfs_rq[i]->shares;
++ }
++
++ if ((!shares && rq_weight) || shares > tg->shares)
++ shares = tg->shares;
++
++ if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
++ shares = tg->shares;
++
++ if (!rq_weight)
++ rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
++
++ for_each_cpu_mask(i, sd->span) {
++ struct rq *rq = cpu_rq(i);
++ unsigned long flags;
++
++ spin_lock_irqsave(&rq->lock, flags);
++ __update_group_shares_cpu(tg, i, shares, rq_weight);
++ spin_unlock_irqrestore(&rq->lock, flags);
++ }
++}
++
++/*
++ * Compute the cpu's hierarchical load factor for each task group.
++ * This needs to be done in a top-down fashion because the load of a child
++ * group is a fraction of its parents load.
++ */
++static void
++tg_load_down(struct task_group *tg, int cpu, struct sched_domain *sd)
++{
++ unsigned long load;
++
++ if (!tg->parent) {
++ load = cpu_rq(cpu)->load.weight;
++ } else {
++ load = tg->parent->cfs_rq[cpu]->h_load;
++ load *= tg->cfs_rq[cpu]->shares;
++ load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
++ }
++
++ tg->cfs_rq[cpu]->h_load = load;
++}
++
++static void
++tg_nop(struct task_group *tg, int cpu, struct sched_domain *sd)
++{
++}
++
++static void update_shares(struct sched_domain *sd)
++{
++ u64 now = cpu_clock(raw_smp_processor_id());
++ s64 elapsed = now - sd->last_update;
++
++ if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
++ sd->last_update = now;
++ walk_tg_tree(tg_nop, tg_shares_up, 0, sd);
++ }
++}
++
++static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
++{
++ spin_unlock(&rq->lock);
++ update_shares(sd);
++ spin_lock(&rq->lock);
++}
++
++static void update_h_load(int cpu)
++{
++ walk_tg_tree(tg_load_down, tg_nop, cpu, NULL);
++}
++
++#else
++
++static inline void update_shares(struct sched_domain *sd)
++{
++}
++
++static inline void update_shares_locked(struct rq *rq, struct sched_domain *sd)
++{
++}
++
++#endif
++
++#endif
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
++{
++#ifdef CONFIG_SMP
++ cfs_rq->shares = shares;
++#endif
++}
++#endif
++
++#include "sched_stats.h"
++#include "sched_idletask.c"
++#include "sched_fair.c"
++#include "sched_rt.c"
++#ifdef CONFIG_SCHED_DEBUG
++# include "sched_debug.c"
++#endif
++
++#define sched_class_highest (&rt_sched_class)
++#define for_each_class(class) \
++ for (class = sched_class_highest; class; class = class->next)
++
++static void inc_nr_running(struct rq *rq)
++{
++ rq->nr_running++;
++}
++
++static void dec_nr_running(struct rq *rq)
++{
++ rq->nr_running--;
++}
++
++static void set_load_weight(struct task_struct *p)
++{
++ if (task_has_rt_policy(p)) {
++ p->se.load.weight = prio_to_weight[0] * 2;
++ p->se.load.inv_weight = prio_to_wmult[0] >> 1;
++ return;
++ }
++
++ /*
++ * SCHED_IDLE tasks get minimal weight:
++ */
++ if (p->policy == SCHED_IDLE) {
++ p->se.load.weight = WEIGHT_IDLEPRIO;
++ p->se.load.inv_weight = WMULT_IDLEPRIO;
++ return;
++ }
++
++ p->se.load.weight = prio_to_weight[p->static_prio - MAX_RT_PRIO];
++ p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
++}
++
++static void update_avg(u64 *avg, u64 sample)
++{
++ s64 diff = sample - *avg;
++ *avg += diff >> 3;
++}
++
++static void enqueue_task(struct rq *rq, struct task_struct *p, int wakeup)
++{
++ // BUG_ON(p->state & TASK_ONHOLD);
++ sched_info_queued(p);
++ p->sched_class->enqueue_task(rq, p, wakeup);
++ p->se.on_rq = 1;
++}
++
++static void dequeue_task(struct rq *rq, struct task_struct *p, int sleep)
++{
++ if (sleep && p->se.last_wakeup) {
++ update_avg(&p->se.avg_overlap,
++ p->se.sum_exec_runtime - p->se.last_wakeup);
++ p->se.last_wakeup = 0;
++ }
++
++ sched_info_dequeued(p);
++ p->sched_class->dequeue_task(rq, p, sleep);
++ p->se.on_rq = 0;
++}
++
++/*
++ * __normal_prio - return the priority that is based on the static prio
++ */
++static inline int __normal_prio(struct task_struct *p)
++{
++ return p->static_prio;
++}
++
++/*
++ * Calculate the expected normal priority: i.e. priority
++ * without taking RT-inheritance into account. Might be
++ * boosted by interactivity modifiers. Changes upon fork,
++ * setprio syscalls, and whenever the interactivity
++ * estimator recalculates.
++ */
++static inline int normal_prio(struct task_struct *p)
++{
++ int prio;
++
++ if (task_has_rt_policy(p))
++ prio = MAX_RT_PRIO-1 - p->rt_priority;
++ else
++ prio = __normal_prio(p);
++ return prio;
++}
++
++/*
++ * Calculate the current priority, i.e. the priority
++ * taken into account by the scheduler. This value might
++ * be boosted by RT tasks, or might be boosted by
++ * interactivity modifiers. Will be RT if the task got
++ * RT-boosted. If not then it returns p->normal_prio.
++ */
++static int effective_prio(struct task_struct *p)
++{
++ p->normal_prio = normal_prio(p);
++ /*
++ * If we are RT tasks or we were boosted to RT priority,
++ * keep the priority unchanged. Otherwise, update priority
++ * to the normal priority:
++ */
++ if (!rt_prio(p->prio))
++ return p->normal_prio;
++ return p->prio;
++}
++
++/*
++ * activate_task - move a task to the runqueue.
++ */
++static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
++{
++ if (task_contributes_to_load(p))
++ rq->nr_uninterruptible--;
++
++ enqueue_task(rq, p, wakeup);
++ inc_nr_running(rq);
++}
++
++/*
++ * deactivate_task - remove a task from the runqueue.
++ */
++static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
++{
++ if (task_contributes_to_load(p))
++ rq->nr_uninterruptible++;
++
++ dequeue_task(rq, p, sleep);
++ dec_nr_running(rq);
++}
++
++/**
++ * task_curr - is this task currently executing on a CPU?
++ * @p: the task in question.
++ */
++inline int task_curr(const struct task_struct *p)
++{
++ return cpu_curr(task_cpu(p)) == p;
++}
++
++static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
++{
++ set_task_rq(p, cpu);
++#ifdef CONFIG_SMP
++ /*
++ * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
++ * successfuly executed on another CPU. We must ensure that updates of
++ * per-task data have been completed by this moment.
++ */
++ smp_wmb();
++ task_thread_info(p)->cpu = cpu;
++#endif
++}
++
++static inline void check_class_changed(struct rq *rq, struct task_struct *p,
++ const struct sched_class *prev_class,
++ int oldprio, int running)
++{
++ if (prev_class != p->sched_class) {
++ if (prev_class->switched_from)
++ prev_class->switched_from(rq, p, running);
++ p->sched_class->switched_to(rq, p, running);
++ } else
++ p->sched_class->prio_changed(rq, p, oldprio, running);
++}
++
++#ifdef CONFIG_SMP
++
++/* Used instead of source_load when we know the type == 0 */
++static unsigned long weighted_cpuload(const int cpu)
++{
++ return cpu_rq(cpu)->load.weight;
++}
++
++/*
++ * Is this task likely cache-hot:
++ */
++static int
++task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
++{
++ s64 delta;
++
++ /*
++ * Buddy candidates are cache hot:
++ */
++ if (sched_feat(CACHE_HOT_BUDDY) && (&p->se == cfs_rq_of(&p->se)->next))
++ return 1;
++
++ if (p->sched_class != &fair_sched_class)
++ return 0;
++
++ if (sysctl_sched_migration_cost == -1)
++ return 1;
++ if (sysctl_sched_migration_cost == 0)
++ return 0;
++
++ delta = now - p->se.exec_start;
++
++ return delta < (s64)sysctl_sched_migration_cost;
++}
++
++
++void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
++{
++ int old_cpu = task_cpu(p);
++ struct rq *old_rq = cpu_rq(old_cpu), *new_rq = cpu_rq(new_cpu);
++ struct cfs_rq *old_cfsrq = task_cfs_rq(p),
++ *new_cfsrq = cpu_cfs_rq(old_cfsrq, new_cpu);
++ u64 clock_offset;
++
++ clock_offset = old_rq->clock - new_rq->clock;
++
++#ifdef CONFIG_SCHEDSTATS
++ if (p->se.wait_start)
++ p->se.wait_start -= clock_offset;
++ if (p->se.sleep_start)
++ p->se.sleep_start -= clock_offset;
++ if (p->se.block_start)
++ p->se.block_start -= clock_offset;
++ if (old_cpu != new_cpu) {
++ schedstat_inc(p, se.nr_migrations);
++ if (task_hot(p, old_rq->clock, NULL))
++ schedstat_inc(p, se.nr_forced2_migrations);
++ }
++#endif
++ p->se.vruntime -= old_cfsrq->min_vruntime -
++ new_cfsrq->min_vruntime;
++
++ __set_task_cpu(p, new_cpu);
++}
++
++struct migration_req {
++ struct list_head list;
++
++ struct task_struct *task;
++ int dest_cpu;
++
++ struct completion done;
++};
++
++#include "sched_mon.h"
++
++
++/*
++ * The task's runqueue lock must be held.
++ * Returns true if you have to wait for migration thread.
++ */
++static int
++migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
++{
++ struct rq *rq = task_rq(p);
++
++ vxm_migrate_task(p, rq, dest_cpu);
++ /*
++ * If the task is not on a runqueue (and not running), then
++ * it is sufficient to simply update the task's cpu field.
++ */
++ if (!p->se.on_rq && !task_running(rq, p)) {
++ set_task_cpu(p, dest_cpu);
++ return 0;
++ }
++
++ init_completion(&req->done);
++ req->task = p;
++ req->dest_cpu = dest_cpu;
++ list_add(&req->list, &rq->migration_queue);
++
++ return 1;
++}
++
++/*
++ * wait_task_inactive - wait for a thread to unschedule.
++ *
++ * If @match_state is nonzero, it's the @p->state value just checked and
++ * not expected to change. If it changes, i.e. @p might have woken up,
++ * then return zero. When we succeed in waiting for @p to be off its CPU,
++ * we return a positive number (its total switch count). If a second call
++ * a short while later returns the same number, the caller can be sure that
++ * @p has remained unscheduled the whole time.
++ *
++ * The caller must ensure that the task *will* unschedule sometime soon,
++ * else this function might spin for a *long* time. This function can't
++ * be called with interrupts off, or it may introduce deadlock with
++ * smp_call_function() if an IPI is sent by the same process we are
++ * waiting to become inactive.
++ */
++unsigned long wait_task_inactive(struct task_struct *p, long match_state)
++{
++ unsigned long flags;
++ int running, on_rq;
++ unsigned long ncsw;
++ struct rq *rq;
++
++ for (;;) {
++ /*
++ * We do the initial early heuristics without holding
++ * any task-queue locks at all. We'll only try to get
++ * the runqueue lock when things look like they will
++ * work out!
++ */
++ rq = task_rq(p);
++
++ /*
++ * If the task is actively running on another CPU
++ * still, just relax and busy-wait without holding
++ * any locks.
++ *
++ * NOTE! Since we don't hold any locks, it's not
++ * even sure that "rq" stays as the right runqueue!
++ * But we don't care, since "task_running()" will
++ * return false if the runqueue has changed and p
++ * is actually now running somewhere else!
++ */
++ while (task_running(rq, p)) {
++ if (match_state && unlikely(p->state != match_state))
++ return 0;
++ cpu_relax();
++ }
++
++ /*
++ * Ok, time to look more closely! We need the rq
++ * lock now, to be *sure*. If we're wrong, we'll
++ * just go back and repeat.
++ */
++ rq = task_rq_lock(p, &flags);
++ running = task_running(rq, p);
++ on_rq = p->se.on_rq;
++ ncsw = 0;
++ if (!match_state || p->state == match_state) {
++ ncsw = p->nivcsw + p->nvcsw;
++ if (unlikely(!ncsw))
++ ncsw = 1;
++ }
++ task_rq_unlock(rq, &flags);
++
++ /*
++ * If it changed from the expected state, bail out now.
++ */
++ if (unlikely(!ncsw))
++ break;
++
++ /*
++ * Was it really running after all now that we
++ * checked with the proper locks actually held?
++ *
++ * Oops. Go back and try again..
++ */
++ if (unlikely(running)) {
++ cpu_relax();
++ continue;
++ }
++
++ /*
++ * It's not enough that it's not actively running,
++ * it must be off the runqueue _entirely_, and not
++ * preempted!
++ *
++ * So if it wa still runnable (but just not actively
++ * running right now), it's preempted, and we should
++ * yield - it could be a while.
++ */
++ if (unlikely(on_rq)) {
++ schedule_timeout_uninterruptible(1);
++ continue;
++ }
++
++ /*
++ * Ahh, all good. It wasn't running, and it wasn't
++ * runnable, which means that it will never become
++ * running in the future either. We're all done!
++ */
++ break;
++ }
++
++ return ncsw;
++}
++
++/***
++ * kick_process - kick a running thread to enter/exit the kernel
++ * @p: the to-be-kicked thread
++ *
++ * Cause a process which is running on another CPU to enter
++ * kernel-mode, without any delay. (to get signals handled.)
++ *
++ * NOTE: this function doesnt have to take the runqueue lock,
++ * because all it wants to ensure is that the remote task enters
++ * the kernel. If the IPI races and the task has been migrated
++ * to another CPU then no harm is done and the purpose has been
++ * achieved as well.
++ */
++void kick_process(struct task_struct *p)
++{
++ int cpu;
++
++ preempt_disable();
++ cpu = task_cpu(p);
++ if ((cpu != smp_processor_id()) && task_curr(p))
++ smp_send_reschedule(cpu);
++ preempt_enable();
++}
++
++/*
++ * Return a low guess at the load of a migration-source cpu weighted
++ * according to the scheduling class and "nice" value.
++ *
++ * We want to under-estimate the load of migration sources, to
++ * balance conservatively.
++ */
++static unsigned long source_load(int cpu, int type)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long total = weighted_cpuload(cpu);
++
++ if (type == 0 || !sched_feat(LB_BIAS))
++ return total;
++
++ return min(rq->cpu_load[type-1], total);
++}
++
++/*
++ * Return a high guess at the load of a migration-target cpu weighted
++ * according to the scheduling class and "nice" value.
++ */
++static unsigned long target_load(int cpu, int type)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long total = weighted_cpuload(cpu);
++
++ if (type == 0 || !sched_feat(LB_BIAS))
++ return total;
++
++ return max(rq->cpu_load[type-1], total);
++}
++
++/*
++ * find_idlest_group finds and returns the least busy CPU group within the
++ * domain.
++ */
++static struct sched_group *
++find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
++{
++ struct sched_group *idlest = NULL, *this = NULL, *group = sd->groups;
++ unsigned long min_load = ULONG_MAX, this_load = 0;
++ int load_idx = sd->forkexec_idx;
++ int imbalance = 100 + (sd->imbalance_pct-100)/2;
++
++ do {
++ unsigned long load, avg_load;
++ int local_group;
++ int i;
++
++ /* Skip over this group if it has no CPUs allowed */
++ if (!cpus_intersects(group->cpumask, p->cpus_allowed))
++ continue;
++
++ local_group = cpu_isset(this_cpu, group->cpumask);
++
++ /* Tally up the load of all CPUs in the group */
++ avg_load = 0;
++
++ for_each_cpu_mask_nr(i, group->cpumask) {
++ /* Bias balancing toward cpus of our domain */
++ if (local_group)
++ load = source_load(i, load_idx);
++ else
++ load = target_load(i, load_idx);
++
++ avg_load += load;
++ }
++
++ /* Adjust by relative CPU power of the group */
++ avg_load = sg_div_cpu_power(group,
++ avg_load * SCHED_LOAD_SCALE);
++
++ if (local_group) {
++ this_load = avg_load;
++ this = group;
++ } else if (avg_load < min_load) {
++ min_load = avg_load;
++ idlest = group;
++ }
++ } while (group = group->next, group != sd->groups);
++
++ if (!idlest || 100*this_load < imbalance*min_load)
++ return NULL;
++ return idlest;
++}
++
++/*
++ * find_idlest_cpu - find the idlest cpu among the cpus in group.
++ */
++static int
++find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu,
++ cpumask_t *tmp)
++{
++ unsigned long load, min_load = ULONG_MAX;
++ int idlest = -1;
++ int i;
++
++ /* Traverse only the allowed CPUs */
++ cpus_and(*tmp, group->cpumask, p->cpus_allowed);
++
++ for_each_cpu_mask_nr(i, *tmp) {
++ load = weighted_cpuload(i);
++
++ if (load < min_load || (load == min_load && i == this_cpu)) {
++ min_load = load;
++ idlest = i;
++ }
++ }
++
++ return idlest;
++}
++
++/*
++ * sched_balance_self: balance the current task (running on cpu) in domains
++ * that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
++ * SD_BALANCE_EXEC.
++ *
++ * Balance, ie. select the least loaded group.
++ *
++ * Returns the target CPU number, or the same CPU if no balancing is needed.
++ *
++ * preempt must be disabled.
++ */
++static int sched_balance_self(int cpu, int flag)
++{
++ struct task_struct *t = current;
++ struct sched_domain *tmp, *sd = NULL;
++
++ for_each_domain(cpu, tmp) {
++ /*
++ * If power savings logic is enabled for a domain, stop there.
++ */
++ if (tmp->flags & SD_POWERSAVINGS_BALANCE)
++ break;
++ if (tmp->flags & flag)
++ sd = tmp;
++ }
++
++ if (sd)
++ update_shares(sd);
++
++ while (sd) {
++ cpumask_t span, tmpmask;
++ struct sched_group *group;
++ int new_cpu, weight;
++
++ if (!(sd->flags & flag)) {
++ sd = sd->child;
++ continue;
++ }
++
++ span = sd->span;
++ group = find_idlest_group(sd, t, cpu);
++ if (!group) {
++ sd = sd->child;
++ continue;
++ }
++
++ new_cpu = find_idlest_cpu(group, t, cpu, &tmpmask);
++ if (new_cpu == -1 || new_cpu == cpu) {
++ /* Now try balancing at a lower domain level of cpu */
++ sd = sd->child;
++ continue;
++ }
++
++ /* Now try balancing at a lower domain level of new_cpu */
++ cpu = new_cpu;
++ sd = NULL;
++ weight = cpus_weight(span);
++ for_each_domain(cpu, tmp) {
++ if (weight <= cpus_weight(tmp->span))
++ break;
++ if (tmp->flags & flag)
++ sd = tmp;
++ }
++ /* while loop will break here if sd == NULL */
++ }
++
++ return cpu;
++}
++
++#endif /* CONFIG_SMP */
++
++/***
++ * try_to_wake_up - wake up a thread
++ * @p: the to-be-woken-up thread
++ * @state: the mask of task states that can be woken
++ * @sync: do a synchronous wakeup?
++ *
++ * Put it on the run-queue if it's not already there. The "current"
++ * thread is always on the run-queue (except when the actual
++ * re-schedule is in progress), and as such you're allowed to do
++ * the simpler "current->state = TASK_RUNNING" to mark yourself
++ * runnable without the overhead of this.
++ *
++ * returns failure only if the task is already active.
++ */
++static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
++{
++ int cpu, orig_cpu, this_cpu, success = 0;
++ unsigned long flags;
++ long old_state;
++ struct rq *rq;
++
++ if (!sched_feat(SYNC_WAKEUPS))
++ sync = 0;
++
++#ifdef CONFIG_SMP
++ if (sched_feat(LB_WAKEUP_UPDATE)) {
++ struct sched_domain *sd;
++
++ this_cpu = raw_smp_processor_id();
++ cpu = task_cpu(p);
++
++ for_each_domain(this_cpu, sd) {
++ if (cpu_isset(cpu, sd->span)) {
++ update_shares(sd);
++ break;
++ }
++ }
++ }
++#endif
++
++ smp_wmb();
++ rq = task_rq_lock(p, &flags);
++ old_state = p->state;
++ if (!(old_state & state))
++ goto out;
++
++ if (p->se.on_rq)
++ goto out_running;
++
++ cpu = task_cpu(p);
++ orig_cpu = cpu;
++ this_cpu = smp_processor_id();
++
++#ifdef CONFIG_SMP
++ if (unlikely(task_running(rq, p)))
++ goto out_activate;
++
++ cpu = p->sched_class->select_task_rq(p, sync);
++ if (cpu != orig_cpu) {
++ set_task_cpu(p, cpu);
++ task_rq_unlock(rq, &flags);
++ /* might preempt at this point */
++ rq = task_rq_lock(p, &flags);
++ old_state = p->state;
++
++ /* we need to unhold suspended tasks
++ if (old_state & TASK_ONHOLD) {
++ vx_unhold_task(p, rq);
++ old_state = p->state;
++ } */
++ if (!(old_state & state))
++ goto out;
++ if (p->se.on_rq)
++ goto out_running;
++
++ this_cpu = smp_processor_id();
++ cpu = task_cpu(p);
++ }
++
++#ifdef CONFIG_SCHEDSTATS
++ schedstat_inc(rq, ttwu_count);
++ if (cpu == this_cpu)
++ schedstat_inc(rq, ttwu_local);
++ else {
++ struct sched_domain *sd;
++ for_each_domain(this_cpu, sd) {
++ if (cpu_isset(cpu, sd->span)) {
++ schedstat_inc(sd, ttwu_wake_remote);
++ break;
++ }
++ }
++ }
++#endif /* CONFIG_SCHEDSTATS */
++
++out_activate:
++#endif /* CONFIG_SMP */
++ schedstat_inc(p, se.nr_wakeups);
++ if (sync)
++ schedstat_inc(p, se.nr_wakeups_sync);
++ if (orig_cpu != cpu)
++ schedstat_inc(p, se.nr_wakeups_migrate);
++ if (cpu == this_cpu)
++ schedstat_inc(p, se.nr_wakeups_local);
++ else
++ schedstat_inc(p, se.nr_wakeups_remote);
++ update_rq_clock(rq);
++ activate_task(rq, p, 1);
++ success = 1;
++
++out_running:
++ trace_mark(kernel_sched_wakeup,
++ "pid %d state %ld ## rq %p task %p rq->curr %p",
++ p->pid, p->state, rq, p, rq->curr);
++ check_preempt_curr(rq, p);
++
++ p->state = TASK_RUNNING;
++#ifdef CONFIG_SMP
++ if (p->sched_class->task_wake_up)
++ p->sched_class->task_wake_up(rq, p);
++#endif
++out:
++ current->se.last_wakeup = current->se.sum_exec_runtime;
++
++ task_rq_unlock(rq, &flags);
++
++ return success;
++}
++
++int wake_up_process(struct task_struct *p)
++{
++ return try_to_wake_up(p, TASK_ALL, 0);
++}
++EXPORT_SYMBOL(wake_up_process);
++
++int wake_up_state(struct task_struct *p, unsigned int state)
++{
++ return try_to_wake_up(p, state, 0);
++}
++
++/*
++ * Perform scheduler related setup for a newly forked process p.
++ * p is forked by current.
++ *
++ * __sched_fork() is basic setup used by init_idle() too:
++ */
++static void __sched_fork(struct task_struct *p)
++{
++ p->se.exec_start = 0;
++ p->se.sum_exec_runtime = 0;
++ p->se.prev_sum_exec_runtime = 0;
++ p->se.last_wakeup = 0;
++ p->se.avg_overlap = 0;
++
++#ifdef CONFIG_SCHEDSTATS
++ p->se.wait_start = 0;
++ p->se.sum_sleep_runtime = 0;
++ p->se.sleep_start = 0;
++ p->se.block_start = 0;
++ p->se.sleep_max = 0;
++ p->se.block_max = 0;
++ p->se.exec_max = 0;
++ p->se.slice_max = 0;
++ p->se.wait_max = 0;
++#endif
++
++ INIT_LIST_HEAD(&p->rt.run_list);
++ p->se.on_rq = 0;
++ INIT_LIST_HEAD(&p->se.group_node);
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++ INIT_HLIST_HEAD(&p->preempt_notifiers);
++#endif
++
++ /*
++ * We mark the process as running here, but have not actually
++ * inserted it onto the runqueue yet. This guarantees that
++ * nobody will actually run it, and a signal or other external
++ * event cannot wake it up and insert it on the runqueue either.
++ */
++ p->state = TASK_RUNNING;
++}
++
++/*
++ * fork()/clone()-time setup:
++ */
++void sched_fork(struct task_struct *p, int clone_flags)
++{
++ int cpu = get_cpu();
++
++ __sched_fork(p);
++
++#ifdef CONFIG_SMP
++ cpu = sched_balance_self(cpu, SD_BALANCE_FORK);
++#endif
++ set_task_cpu(p, cpu);
++
++ /*
++ * Make sure we do not leak PI boosting priority to the child:
++ */
++ p->prio = current->normal_prio;
++ if (!rt_prio(p->prio))
++ p->sched_class = &fair_sched_class;
++
++#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
++ if (likely(sched_info_on()))
++ memset(&p->sched_info, 0, sizeof(p->sched_info));
++#endif
++#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
++ p->oncpu = 0;
++#endif
++#ifdef CONFIG_PREEMPT
++ /* Want to start with kernel preemption disabled. */
++ task_thread_info(p)->preempt_count = 1;
++#endif
++ put_cpu();
++}
++
++/*
++ * wake_up_new_task - wake up a newly created task for the first time.
++ *
++ * This function will do some initial scheduler statistics housekeeping
++ * that must be done for every newly created context, then puts the task
++ * on the runqueue and wakes it.
++ */
++void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
++{
++ unsigned long flags;
++ struct rq *rq;
++
++ rq = task_rq_lock(p, &flags);
++ BUG_ON(p->state != TASK_RUNNING);
++ update_rq_clock(rq);
++
++ p->prio = effective_prio(p);
++
++ if (!p->sched_class->task_new || !current->se.on_rq) {
++ activate_task(rq, p, 0);
++ } else {
++ /*
++ * Let the scheduling class do new task startup
++ * management (if any):
++ */
++ p->sched_class->task_new(rq, p);
++ inc_nr_running(rq);
++ }
++ trace_mark(kernel_sched_wakeup_new,
++ "pid %d state %ld ## rq %p task %p rq->curr %p",
++ p->pid, p->state, rq, p, rq->curr);
++ check_preempt_curr(rq, p);
++#ifdef CONFIG_SMP
++ if (p->sched_class->task_wake_up)
++ p->sched_class->task_wake_up(rq, p);
++#endif
++ task_rq_unlock(rq, &flags);
++}
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++
++/**
++ * preempt_notifier_register - tell me when current is being being preempted & rescheduled
++ * @notifier: notifier struct to register
++ */
++void preempt_notifier_register(struct preempt_notifier *notifier)
++{
++ hlist_add_head(¬ifier->link, ¤t->preempt_notifiers);
++}
++EXPORT_SYMBOL_GPL(preempt_notifier_register);
++
++/**
++ * preempt_notifier_unregister - no longer interested in preemption notifications
++ * @notifier: notifier struct to unregister
++ *
++ * This is safe to call from within a preemption notifier.
++ */
++void preempt_notifier_unregister(struct preempt_notifier *notifier)
++{
++ hlist_del(¬ifier->link);
++}
++EXPORT_SYMBOL_GPL(preempt_notifier_unregister);
++
++static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
++{
++ struct preempt_notifier *notifier;
++ struct hlist_node *node;
++
++ hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
++ notifier->ops->sched_in(notifier, raw_smp_processor_id());
++}
++
++static void
++fire_sched_out_preempt_notifiers(struct task_struct *curr,
++ struct task_struct *next)
++{
++ struct preempt_notifier *notifier;
++ struct hlist_node *node;
++
++ hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
++ notifier->ops->sched_out(notifier, next);
++}
++
++#else /* !CONFIG_PREEMPT_NOTIFIERS */
++
++static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
++{
++}
++
++static void
++fire_sched_out_preempt_notifiers(struct task_struct *curr,
++ struct task_struct *next)
++{
++}
++
++#endif /* CONFIG_PREEMPT_NOTIFIERS */
++
++/**
++ * prepare_task_switch - prepare to switch tasks
++ * @rq: the runqueue preparing to switch
++ * @prev: the current task that is being switched out
++ * @next: the task we are going to switch to.
++ *
++ * This is called with the rq lock held and interrupts off. It must
++ * be paired with a subsequent finish_task_switch after the context
++ * switch.
++ *
++ * prepare_task_switch sets up locking and calls architecture specific
++ * hooks.
++ */
++static inline void
++prepare_task_switch(struct rq *rq, struct task_struct *prev,
++ struct task_struct *next)
++{
++ fire_sched_out_preempt_notifiers(prev, next);
++ prepare_lock_switch(rq, next);
++ prepare_arch_switch(next);
++}
++
++/**
++ * finish_task_switch - clean up after a task-switch
++ * @rq: runqueue associated with task-switch
++ * @prev: the thread we just switched away from.
++ *
++ * finish_task_switch must be called after the context switch, paired
++ * with a prepare_task_switch call before the context switch.
++ * finish_task_switch will reconcile locking set up by prepare_task_switch,
++ * and do any other architecture-specific cleanup actions.
++ *
++ * Note that we may have delayed dropping an mm in context_switch(). If
++ * so, we finish that here outside of the runqueue lock. (Doing it
++ * with the lock held can cause deadlocks; see schedule() for
++ * details.)
++ */
++static void finish_task_switch(struct rq *rq, struct task_struct *prev)
++ __releases(rq->lock)
++{
++ struct mm_struct *mm = rq->prev_mm;
++ long prev_state;
++
++ rq->prev_mm = NULL;
++
++ /*
++ * A task struct has one reference for the use as "current".
++ * If a task dies, then it sets TASK_DEAD in tsk->state and calls
++ * schedule one last time. The schedule call will never return, and
++ * the scheduled task must drop that reference.
++ * The test for TASK_DEAD must occur while the runqueue locks are
++ * still held, otherwise prev could be scheduled on another cpu, die
++ * there before we look at prev->state, and then the reference would
++ * be dropped twice.
++ * Manfred Spraul <manfred@colorfullife.com>
++ */
++ prev_state = prev->state;
++ finish_arch_switch(prev);
++ finish_lock_switch(rq, prev);
++#ifdef CONFIG_SMP
++ if (current->sched_class->post_schedule)
++ current->sched_class->post_schedule(rq);
++#endif
++
++ fire_sched_in_preempt_notifiers(current);
++ if (mm)
++ mmdrop(mm);
++ if (unlikely(prev_state == TASK_DEAD)) {
++ /*
++ * Remove function-return probe instances associated with this
++ * task and put them back on the free list.
++ */
++ kprobe_flush_task(prev);
++ put_task_struct(prev);
++ }
++}
++
++/**
++ * schedule_tail - first thing a freshly forked thread must call.
++ * @prev: the thread we just switched away from.
++ */
++asmlinkage void schedule_tail(struct task_struct *prev)
++ __releases(rq->lock)
++{
++ struct rq *rq = this_rq();
++
++ finish_task_switch(rq, prev);
++#ifdef __ARCH_WANT_UNLOCKED_CTXSW
++ /* In this case, finish_task_switch does not reenable preemption */
++ preempt_enable();
++#endif
++ if (current->set_child_tid)
++ put_user(task_pid_vnr(current), current->set_child_tid);
++}
++
++/*
++ * context_switch - switch to the new MM and the new
++ * thread's register state.
++ */
++static inline void
++context_switch(struct rq *rq, struct task_struct *prev,
++ struct task_struct *next)
++{
++ struct mm_struct *mm, *oldmm;
++
++ prepare_task_switch(rq, prev, next);
++ trace_mark(kernel_sched_schedule,
++ "prev_pid %d next_pid %d prev_state %ld "
++ "## rq %p prev %p next %p",
++ prev->pid, next->pid, prev->state,
++ rq, prev, next);
++ mm = next->mm;
++ oldmm = prev->active_mm;
++ /*
++ * For paravirt, this is coupled with an exit in switch_to to
++ * combine the page table reload and the switch backend into
++ * one hypercall.
++ */
++ arch_enter_lazy_cpu_mode();
++
++ if (unlikely(!mm)) {
++ next->active_mm = oldmm;
++ atomic_inc(&oldmm->mm_count);
++ enter_lazy_tlb(oldmm, next);
++ } else
++ switch_mm(oldmm, mm, next);
++
++ if (unlikely(!prev->mm)) {
++ prev->active_mm = NULL;
++ rq->prev_mm = oldmm;
++ }
++ /*
++ * Since the runqueue lock will be released by the next
++ * task (which is an invalid locking op but in the case
++ * of the scheduler it's an obvious special-case), so we
++ * do an early lockdep release here:
++ */
++#ifndef __ARCH_WANT_UNLOCKED_CTXSW
++ spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
++#endif
++
++ /* Here we just switch the register state and the stack. */
++ switch_to(prev, next, prev);
++
++ barrier();
++ /*
++ * this_rq must be evaluated again because prev may have moved
++ * CPUs since it called schedule(), thus the 'rq' on its stack
++ * frame will be invalid.
++ */
++ finish_task_switch(this_rq(), prev);
++}
++
++/*
++ * nr_running, nr_uninterruptible and nr_context_switches:
++ *
++ * externally visible scheduler statistics: current number of runnable
++ * threads, current number of uninterruptible-sleeping threads, total
++ * number of context switches performed since bootup.
++ */
++unsigned long nr_running(void)
++{
++ unsigned long i, sum = 0;
++
++ for_each_online_cpu(i)
++ sum += cpu_rq(i)->nr_running;
++
++ return sum;
++}
++
++unsigned long nr_uninterruptible(void)
++{
++ unsigned long i, sum = 0;
++
++ for_each_possible_cpu(i)
++ sum += cpu_rq(i)->nr_uninterruptible;
++
++ /*
++ * Since we read the counters lockless, it might be slightly
++ * inaccurate. Do not allow it to go below zero though:
++ */
++ if (unlikely((long)sum < 0))
++ sum = 0;
++
++ return sum;
++}
++
++unsigned long long nr_context_switches(void)
++{
++ int i;
++ unsigned long long sum = 0;
++
++ for_each_possible_cpu(i)
++ sum += cpu_rq(i)->nr_switches;
++
++ return sum;
++}
++
++unsigned long nr_iowait(void)
++{
++ unsigned long i, sum = 0;
++
++ for_each_possible_cpu(i)
++ sum += atomic_read(&cpu_rq(i)->nr_iowait);
++
++ return sum;
++}
++
++unsigned long nr_active(void)
++{
++ unsigned long i, running = 0, uninterruptible = 0;
++
++ for_each_online_cpu(i) {
++ running += cpu_rq(i)->nr_running;
++ uninterruptible += cpu_rq(i)->nr_uninterruptible;
++ }
++
++ if (unlikely((long)uninterruptible < 0))
++ uninterruptible = 0;
++
++ return running + uninterruptible;
++}
++
++/*
++ * Update rq->cpu_load[] statistics. This function is usually called every
++ * scheduler tick (TICK_NSEC).
++ */
++static void update_cpu_load(struct rq *this_rq)
++{
++ unsigned long this_load = this_rq->load.weight;
++ int i, scale;
++
++ this_rq->nr_load_updates++;
++
++ /* Update our load: */
++ for (i = 0, scale = 1; i < CPU_LOAD_IDX_MAX; i++, scale += scale) {
++ unsigned long old_load, new_load;
++
++ /* scale is effectively 1 << i now, and >> i divides by scale */
++
++ old_load = this_rq->cpu_load[i];
++ new_load = this_load;
++ /*
++ * Round up the averaging division if load is increasing. This
++ * prevents us from getting stuck on 9 if the load is 10, for
++ * example.
++ */
++ if (new_load > old_load)
++ new_load += scale-1;
++ this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i;
++ }
++}
++
++#ifdef CONFIG_SMP
++
++/*
++ * double_rq_lock - safely lock two runqueues
++ *
++ * Note this does not disable interrupts like task_rq_lock,
++ * you need to do so manually before calling.
++ */
++static void double_rq_lock(struct rq *rq1, struct rq *rq2)
++ __acquires(rq1->lock)
++ __acquires(rq2->lock)
++{
++ BUG_ON(!irqs_disabled());
++ if (rq1 == rq2) {
++ spin_lock(&rq1->lock);
++ __acquire(rq2->lock); /* Fake it out ;) */
++ } else {
++ if (rq1 < rq2) {
++ spin_lock(&rq1->lock);
++ spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
++ } else {
++ spin_lock(&rq2->lock);
++ spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
++ }
++ }
++ update_rq_clock(rq1);
++ update_rq_clock(rq2);
++}
++
++/*
++ * double_rq_unlock - safely unlock two runqueues
++ *
++ * Note this does not restore interrupts like task_rq_unlock,
++ * you need to do so manually after calling.
++ */
++static void double_rq_unlock(struct rq *rq1, struct rq *rq2)
++ __releases(rq1->lock)
++ __releases(rq2->lock)
++{
++ spin_unlock(&rq1->lock);
++ if (rq1 != rq2)
++ spin_unlock(&rq2->lock);
++ else
++ __release(rq2->lock);
++}
++
++/*
++ * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
++ */
++static int double_lock_balance(struct rq *this_rq, struct rq *busiest)
++ __releases(this_rq->lock)
++ __acquires(busiest->lock)
++ __acquires(this_rq->lock)
++{
++ int ret = 0;
++
++ if (unlikely(!irqs_disabled())) {
++ /* printk() doesn't work good under rq->lock */
++ spin_unlock(&this_rq->lock);
++ BUG_ON(1);
++ }
++ if (unlikely(!spin_trylock(&busiest->lock))) {
++ if (busiest < this_rq) {
++ spin_unlock(&this_rq->lock);
++ spin_lock(&busiest->lock);
++ spin_lock_nested(&this_rq->lock, SINGLE_DEPTH_NESTING);
++ ret = 1;
++ } else
++ spin_lock_nested(&busiest->lock, SINGLE_DEPTH_NESTING);
++ }
++ return ret;
++}
++
++static void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
++ __releases(busiest->lock)
++{
++ spin_unlock(&busiest->lock);
++ lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
++}
++
++/*
++ * If dest_cpu is allowed for this process, migrate the task to it.
++ * This is accomplished by forcing the cpu_allowed mask to only
++ * allow dest_cpu, which will force the cpu onto dest_cpu. Then
++ * the cpu_allowed mask is restored.
++ */
++static void sched_migrate_task(struct task_struct *p, int dest_cpu)
++{
++ struct migration_req req;
++ unsigned long flags;
++ struct rq *rq;
++
++ rq = task_rq_lock(p, &flags);
++ if (!cpu_isset(dest_cpu, p->cpus_allowed)
++ || unlikely(!cpu_active(dest_cpu)))
++ goto out;
++
++ /* force the process onto the specified CPU */
++ if (migrate_task(p, dest_cpu, &req)) {
++ /* Need to wait for migration thread (might exit: take ref). */
++ struct task_struct *mt = rq->migration_thread;
++
++ get_task_struct(mt);
++ task_rq_unlock(rq, &flags);
++ wake_up_process(mt);
++ put_task_struct(mt);
++ wait_for_completion(&req.done);
++
++ return;
++ }
++out:
++ task_rq_unlock(rq, &flags);
++}
++
++/*
++ * sched_exec - execve() is a valuable balancing opportunity, because at
++ * this point the task has the smallest effective memory and cache footprint.
++ */
++void sched_exec(void)
++{
++ int new_cpu, this_cpu = get_cpu();
++ new_cpu = sched_balance_self(this_cpu, SD_BALANCE_EXEC);
++ put_cpu();
++ if (new_cpu != this_cpu)
++ sched_migrate_task(current, new_cpu);
++}
++
++/*
++ * pull_task - move a task from a remote runqueue to the local runqueue.
++ * Both runqueues must be locked.
++ */
++static void pull_task(struct rq *src_rq, struct task_struct *p,
++ struct rq *this_rq, int this_cpu)
++{
++ deactivate_task(src_rq, p, 0);
++ set_task_cpu(p, this_cpu);
++ activate_task(this_rq, p, 0);
++ /*
++ * Note that idle threads have a prio of MAX_PRIO, for this test
++ * to be always true for them.
++ */
++ check_preempt_curr(this_rq, p);
++}
++
++/*
++ * can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
++ */
++static
++int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
++ struct sched_domain *sd, enum cpu_idle_type idle,
++ int *all_pinned)
++{
++ /*
++ * We do not migrate tasks that are:
++ * 1) running (obviously), or
++ * 2) cannot be migrated to this CPU due to cpus_allowed, or
++ * 3) are cache-hot on their current CPU.
++ */
++ if (!cpu_isset(this_cpu, p->cpus_allowed)) {
++ schedstat_inc(p, se.nr_failed_migrations_affine);
++ return 0;
++ }
++ *all_pinned = 0;
++
++ if (task_running(rq, p)) {
++ schedstat_inc(p, se.nr_failed_migrations_running);
++ return 0;
++ }
++
++ /*
++ * Aggressive migration if:
++ * 1) task is cache cold, or
++ * 2) too many balance attempts have failed.
++ */
++
++ if (!task_hot(p, rq->clock, sd) ||
++ sd->nr_balance_failed > sd->cache_nice_tries) {
++#ifdef CONFIG_SCHEDSTATS
++ if (task_hot(p, rq->clock, sd)) {
++ schedstat_inc(sd, lb_hot_gained[idle]);
++ schedstat_inc(p, se.nr_forced_migrations);
++ }
++#endif
++ return 1;
++ }
++
++ if (task_hot(p, rq->clock, sd)) {
++ schedstat_inc(p, se.nr_failed_migrations_hot);
++ return 0;
++ }
++ return 1;
++}
++
++static unsigned long
++balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ unsigned long max_load_move, struct sched_domain *sd,
++ enum cpu_idle_type idle, int *all_pinned,
++ int *this_best_prio, struct rq_iterator *iterator)
++{
++ int loops = 0, pulled = 0, pinned = 0;
++ struct task_struct *p;
++ long rem_load_move = max_load_move;
++
++ if (max_load_move == 0)
++ goto out;
++
++ pinned = 1;
++
++ /*
++ * Start the load-balancing iterator:
++ */
++ p = iterator->start(iterator->arg);
++next:
++ if (!p || loops++ > sysctl_sched_nr_migrate)
++ goto out;
++
++ if ((p->se.load.weight >> 1) > rem_load_move ||
++ !can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) {
++ p = iterator->next(iterator->arg);
++ goto next;
++ }
++
++ pull_task(busiest, p, this_rq, this_cpu);
++ pulled++;
++ rem_load_move -= p->se.load.weight;
++
++ /*
++ * We only want to steal up to the prescribed amount of weighted load.
++ */
++ if (rem_load_move > 0) {
++ if (p->prio < *this_best_prio)
++ *this_best_prio = p->prio;
++ p = iterator->next(iterator->arg);
++ goto next;
++ }
++out:
++ /*
++ * Right now, this is one of only two places pull_task() is called,
++ * so we can safely collect pull_task() stats here rather than
++ * inside pull_task().
++ */
++ schedstat_add(sd, lb_gained[idle], pulled);
++
++ if (all_pinned)
++ *all_pinned = pinned;
++
++ return max_load_move - rem_load_move;
++}
++
++/*
++ * move_tasks tries to move up to max_load_move weighted load from busiest to
++ * this_rq, as part of a balancing operation within domain "sd".
++ * Returns 1 if successful and 0 otherwise.
++ *
++ * Called with both runqueues locked.
++ */
++static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ unsigned long max_load_move,
++ struct sched_domain *sd, enum cpu_idle_type idle,
++ int *all_pinned)
++{
++ const struct sched_class *class = sched_class_highest;
++ unsigned long total_load_moved = 0;
++ int this_best_prio = this_rq->curr->prio;
++
++ do {
++ total_load_moved +=
++ class->load_balance(this_rq, this_cpu, busiest,
++ max_load_move - total_load_moved,
++ sd, idle, all_pinned, &this_best_prio);
++ class = class->next;
++
++ if (idle == CPU_NEWLY_IDLE && this_rq->nr_running)
++ break;
++
++ } while (class && max_load_move > total_load_moved);
++
++ return total_load_moved > 0;
++}
++
++static int
++iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ struct sched_domain *sd, enum cpu_idle_type idle,
++ struct rq_iterator *iterator)
++{
++ struct task_struct *p = iterator->start(iterator->arg);
++ int pinned = 0;
++
++ while (p) {
++ if (can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) {
++ pull_task(busiest, p, this_rq, this_cpu);
++ /*
++ * Right now, this is only the second place pull_task()
++ * is called, so we can safely collect pull_task()
++ * stats here rather than inside pull_task().
++ */
++ schedstat_inc(sd, lb_gained[idle]);
++
++ return 1;
++ }
++ p = iterator->next(iterator->arg);
++ }
++
++ return 0;
++}
++
++/*
++ * move_one_task tries to move exactly one task from busiest to this_rq, as
++ * part of active balancing operations within "domain".
++ * Returns 1 if successful and 0 otherwise.
++ *
++ * Called with both runqueues locked.
++ */
++static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
++ struct sched_domain *sd, enum cpu_idle_type idle)
++{
++ const struct sched_class *class;
++
++ for (class = sched_class_highest; class; class = class->next)
++ if (class->move_one_task(this_rq, this_cpu, busiest, sd, idle))
++ return 1;
++
++ return 0;
++}
++
++/*
++ * find_busiest_group finds and returns the busiest CPU group within the
++ * domain. It calculates and returns the amount of weighted load which
++ * should be moved to restore balance via the imbalance parameter.
++ */
++static struct sched_group *
++find_busiest_group(struct sched_domain *sd, int this_cpu,
++ unsigned long *imbalance, enum cpu_idle_type idle,
++ int *sd_idle, const cpumask_t *cpus, int *balance)
++{
++ struct sched_group *busiest = NULL, *this = NULL, *group = sd->groups;
++ unsigned long max_load, avg_load, total_load, this_load, total_pwr;
++ unsigned long max_pull;
++ unsigned long busiest_load_per_task, busiest_nr_running;
++ unsigned long this_load_per_task, this_nr_running;
++ int load_idx, group_imb = 0;
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++ int power_savings_balance = 1;
++ unsigned long leader_nr_running = 0, min_load_per_task = 0;
++ unsigned long min_nr_running = ULONG_MAX;
++ struct sched_group *group_min = NULL, *group_leader = NULL;
++#endif
++
++ max_load = this_load = total_load = total_pwr = 0;
++ busiest_load_per_task = busiest_nr_running = 0;
++ this_load_per_task = this_nr_running = 0;
++
++ if (idle == CPU_NOT_IDLE)
++ load_idx = sd->busy_idx;
++ else if (idle == CPU_NEWLY_IDLE)
++ load_idx = sd->newidle_idx;
++ else
++ load_idx = sd->idle_idx;
++
++ do {
++ unsigned long load, group_capacity, max_cpu_load, min_cpu_load;
++ int local_group;
++ int i;
++ int __group_imb = 0;
++ unsigned int balance_cpu = -1, first_idle_cpu = 0;
++ unsigned long sum_nr_running, sum_weighted_load;
++ unsigned long sum_avg_load_per_task;
++ unsigned long avg_load_per_task;
++
++ local_group = cpu_isset(this_cpu, group->cpumask);
++
++ if (local_group)
++ balance_cpu = first_cpu(group->cpumask);
++
++ /* Tally up the load of all CPUs in the group */
++ sum_weighted_load = sum_nr_running = avg_load = 0;
++ sum_avg_load_per_task = avg_load_per_task = 0;
++
++ max_cpu_load = 0;
++ min_cpu_load = ~0UL;
++
++ for_each_cpu_mask_nr(i, group->cpumask) {
++ struct rq *rq;
++
++ if (!cpu_isset(i, *cpus))
++ continue;
++
++ rq = cpu_rq(i);
++
++ if (*sd_idle && rq->nr_running)
++ *sd_idle = 0;
++
++ /* Bias balancing toward cpus of our domain */
++ if (local_group) {
++ if (idle_cpu(i) && !first_idle_cpu) {
++ first_idle_cpu = 1;
++ balance_cpu = i;
++ }
++
++ load = target_load(i, load_idx);
++ } else {
++ load = source_load(i, load_idx);
++ if (load > max_cpu_load)
++ max_cpu_load = load;
++ if (min_cpu_load > load)
++ min_cpu_load = load;
++ }
++
++ avg_load += load;
++ sum_nr_running += rq->nr_running;
++ sum_weighted_load += weighted_cpuload(i);
++
++ sum_avg_load_per_task += cpu_avg_load_per_task(i);
++ }
++
++ /*
++ * First idle cpu or the first cpu(busiest) in this sched group
++ * is eligible for doing load balancing at this and above
++ * domains. In the newly idle case, we will allow all the cpu's
++ * to do the newly idle load balance.
++ */
++ if (idle != CPU_NEWLY_IDLE && local_group &&
++ balance_cpu != this_cpu && balance) {
++ *balance = 0;
++ goto ret;
++ }
++
++ total_load += avg_load;
++ total_pwr += group->__cpu_power;
++
++ /* Adjust by relative CPU power of the group */
++ avg_load = sg_div_cpu_power(group,
++ avg_load * SCHED_LOAD_SCALE);
++
++
++ /*
++ * Consider the group unbalanced when the imbalance is larger
++ * than the average weight of two tasks.
++ *
++ * APZ: with cgroup the avg task weight can vary wildly and
++ * might not be a suitable number - should we keep a
++ * normalized nr_running number somewhere that negates
++ * the hierarchy?
++ */
++ avg_load_per_task = sg_div_cpu_power(group,
++ sum_avg_load_per_task * SCHED_LOAD_SCALE);
++
++ if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task)
++ __group_imb = 1;
++
++ group_capacity = group->__cpu_power / SCHED_LOAD_SCALE;
++
++ if (local_group) {
++ this_load = avg_load;
++ this = group;
++ this_nr_running = sum_nr_running;
++ this_load_per_task = sum_weighted_load;
++ } else if (avg_load > max_load &&
++ (sum_nr_running > group_capacity || __group_imb)) {
++ max_load = avg_load;
++ busiest = group;
++ busiest_nr_running = sum_nr_running;
++ busiest_load_per_task = sum_weighted_load;
++ group_imb = __group_imb;
++ }
++
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++ /*
++ * Busy processors will not participate in power savings
++ * balance.
++ */
++ if (idle == CPU_NOT_IDLE ||
++ !(sd->flags & SD_POWERSAVINGS_BALANCE))
++ goto group_next;
++
++ /*
++ * If the local group is idle or completely loaded
++ * no need to do power savings balance at this domain
++ */
++ if (local_group && (this_nr_running >= group_capacity ||
++ !this_nr_running))
++ power_savings_balance = 0;
++
++ /*
++ * If a group is already running at full capacity or idle,
++ * don't include that group in power savings calculations
++ */
++ if (!power_savings_balance || sum_nr_running >= group_capacity
++ || !sum_nr_running)
++ goto group_next;
++
++ /*
++ * Calculate the group which has the least non-idle load.
++ * This is the group from where we need to pick up the load
++ * for saving power
++ */
++ if ((sum_nr_running < min_nr_running) ||
++ (sum_nr_running == min_nr_running &&
++ first_cpu(group->cpumask) <
++ first_cpu(group_min->cpumask))) {
++ group_min = group;
++ min_nr_running = sum_nr_running;
++ min_load_per_task = sum_weighted_load /
++ sum_nr_running;
++ }
++
++ /*
++ * Calculate the group which is almost near its
++ * capacity but still has some space to pick up some load
++ * from other group and save more power
++ */
++ if (sum_nr_running <= group_capacity - 1) {
++ if (sum_nr_running > leader_nr_running ||
++ (sum_nr_running == leader_nr_running &&
++ first_cpu(group->cpumask) >
++ first_cpu(group_leader->cpumask))) {
++ group_leader = group;
++ leader_nr_running = sum_nr_running;
++ }
++ }
++group_next:
++#endif
++ group = group->next;
++ } while (group != sd->groups);
++
++ if (!busiest || this_load >= max_load || busiest_nr_running == 0)
++ goto out_balanced;
++
++ avg_load = (SCHED_LOAD_SCALE * total_load) / total_pwr;
++
++ if (this_load >= avg_load ||
++ 100*max_load <= sd->imbalance_pct*this_load)
++ goto out_balanced;
++
++ busiest_load_per_task /= busiest_nr_running;
++ if (group_imb)
++ busiest_load_per_task = min(busiest_load_per_task, avg_load);
++
++ /*
++ * We're trying to get all the cpus to the average_load, so we don't
++ * want to push ourselves above the average load, nor do we wish to
++ * reduce the max loaded cpu below the average load, as either of these
++ * actions would just result in more rebalancing later, and ping-pong
++ * tasks around. Thus we look for the minimum possible imbalance.
++ * Negative imbalances (*we* are more loaded than anyone else) will
++ * be counted as no imbalance for these purposes -- we can't fix that
++ * by pulling tasks to us. Be careful of negative numbers as they'll
++ * appear as very large values with unsigned longs.
++ */
++ if (max_load <= busiest_load_per_task)
++ goto out_balanced;
++
++ /*
++ * In the presence of smp nice balancing, certain scenarios can have
++ * max load less than avg load(as we skip the groups at or below
++ * its cpu_power, while calculating max_load..)
++ */
++ if (max_load < avg_load) {
++ *imbalance = 0;
++ goto small_imbalance;
++ }
++
++ /* Don't want to pull so many tasks that a group would go idle */
++ max_pull = min(max_load - avg_load, max_load - busiest_load_per_task);
++
++ /* How much load to actually move to equalise the imbalance */
++ *imbalance = min(max_pull * busiest->__cpu_power,
++ (avg_load - this_load) * this->__cpu_power)
++ / SCHED_LOAD_SCALE;
++
++ /*
++ * if *imbalance is less than the average load per runnable task
++ * there is no gaurantee that any tasks will be moved so we'll have
++ * a think about bumping its value to force at least one task to be
++ * moved
++ */
++ if (*imbalance < busiest_load_per_task) {
++ unsigned long tmp, pwr_now, pwr_move;
++ unsigned int imbn;
++
++small_imbalance:
++ pwr_move = pwr_now = 0;
++ imbn = 2;
++ if (this_nr_running) {
++ this_load_per_task /= this_nr_running;
++ if (busiest_load_per_task > this_load_per_task)
++ imbn = 1;
++ } else
++ this_load_per_task = cpu_avg_load_per_task(this_cpu);
++
++ if (max_load - this_load + 2*busiest_load_per_task >=
++ busiest_load_per_task * imbn) {
++ *imbalance = busiest_load_per_task;
++ return busiest;
++ }
++
++ /*
++ * OK, we don't have enough imbalance to justify moving tasks,
++ * however we may be able to increase total CPU power used by
++ * moving them.
++ */
++
++ pwr_now += busiest->__cpu_power *
++ min(busiest_load_per_task, max_load);
++ pwr_now += this->__cpu_power *
++ min(this_load_per_task, this_load);
++ pwr_now /= SCHED_LOAD_SCALE;
++
++ /* Amount of load we'd subtract */
++ tmp = sg_div_cpu_power(busiest,
++ busiest_load_per_task * SCHED_LOAD_SCALE);
++ if (max_load > tmp)
++ pwr_move += busiest->__cpu_power *
++ min(busiest_load_per_task, max_load - tmp);
++
++ /* Amount of load we'd add */
++ if (max_load * busiest->__cpu_power <
++ busiest_load_per_task * SCHED_LOAD_SCALE)
++ tmp = sg_div_cpu_power(this,
++ max_load * busiest->__cpu_power);
++ else
++ tmp = sg_div_cpu_power(this,
++ busiest_load_per_task * SCHED_LOAD_SCALE);
++ pwr_move += this->__cpu_power *
++ min(this_load_per_task, this_load + tmp);
++ pwr_move /= SCHED_LOAD_SCALE;
++
++ /* Move if we gain throughput */
++ if (pwr_move > pwr_now)
++ *imbalance = busiest_load_per_task;
++ }
++
++ return busiest;
++
++out_balanced:
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++ if (idle == CPU_NOT_IDLE || !(sd->flags & SD_POWERSAVINGS_BALANCE))
++ goto ret;
++
++ if (this == group_leader && group_leader != group_min) {
++ *imbalance = min_load_per_task;
++ return group_min;
++ }
++#endif
++ret:
++ *imbalance = 0;
++ return NULL;
++}
++
++/*
++ * find_busiest_queue - find the busiest runqueue among the cpus in group.
++ */
++static struct rq *
++find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle,
++ unsigned long imbalance, const cpumask_t *cpus)
++{
++ struct rq *busiest = NULL, *rq;
++ unsigned long max_load = 0;
++ int i;
++
++ for_each_cpu_mask_nr(i, group->cpumask) {
++ unsigned long wl;
++
++ if (!cpu_isset(i, *cpus))
++ continue;
++
++ rq = cpu_rq(i);
++ wl = weighted_cpuload(i);
++
++ if (rq->nr_running == 1 && wl > imbalance)
++ continue;
++
++ if (wl > max_load) {
++ max_load = wl;
++ busiest = rq;
++ }
++ }
++
++ return busiest;
++}
++
++/*
++ * Max backoff if we encounter pinned tasks. Pretty arbitrary value, but
++ * so long as it is large enough.
++ */
++#define MAX_PINNED_INTERVAL 512
++
++/*
++ * Check this_cpu to ensure it is balanced within domain. Attempt to move
++ * tasks if there is an imbalance.
++ */
++static int load_balance(int this_cpu, struct rq *this_rq,
++ struct sched_domain *sd, enum cpu_idle_type idle,
++ int *balance, cpumask_t *cpus)
++{
++ int ld_moved, all_pinned = 0, active_balance = 0, sd_idle = 0;
++ struct sched_group *group;
++ unsigned long imbalance;
++ struct rq *busiest;
++ unsigned long flags;
++
++ cpus_setall(*cpus);
++
++ /*
++ * When power savings policy is enabled for the parent domain, idle
++ * sibling can pick up load irrespective of busy siblings. In this case,
++ * let the state of idle sibling percolate up as CPU_IDLE, instead of
++ * portraying it as CPU_NOT_IDLE.
++ */
++ if (idle != CPU_NOT_IDLE && sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ sd_idle = 1;
++
++ schedstat_inc(sd, lb_count[idle]);
++
++redo:
++ update_shares(sd);
++ group = find_busiest_group(sd, this_cpu, &imbalance, idle, &sd_idle,
++ cpus, balance);
++
++ if (*balance == 0)
++ goto out_balanced;
++
++ if (!group) {
++ schedstat_inc(sd, lb_nobusyg[idle]);
++ goto out_balanced;
++ }
++
++ busiest = find_busiest_queue(group, idle, imbalance, cpus);
++ if (!busiest) {
++ schedstat_inc(sd, lb_nobusyq[idle]);
++ goto out_balanced;
++ }
++
++ BUG_ON(busiest == this_rq);
++
++ schedstat_add(sd, lb_imbalance[idle], imbalance);
++
++ ld_moved = 0;
++ if (busiest->nr_running > 1) {
++ /*
++ * Attempt to move tasks. If find_busiest_group has found
++ * an imbalance but busiest->nr_running <= 1, the group is
++ * still unbalanced. ld_moved simply stays zero, so it is
++ * correctly treated as an imbalance.
++ */
++ local_irq_save(flags);
++ double_rq_lock(this_rq, busiest);
++ ld_moved = move_tasks(this_rq, this_cpu, busiest,
++ imbalance, sd, idle, &all_pinned);
++ double_rq_unlock(this_rq, busiest);
++ local_irq_restore(flags);
++
++ /*
++ * some other cpu did the load balance for us.
++ */
++ if (ld_moved && this_cpu != smp_processor_id())
++ resched_cpu(this_cpu);
++
++ /* All tasks on this runqueue were pinned by CPU affinity */
++ if (unlikely(all_pinned)) {
++ cpu_clear(cpu_of(busiest), *cpus);
++ if (!cpus_empty(*cpus))
++ goto redo;
++ goto out_balanced;
++ }
++ }
++
++ if (!ld_moved) {
++ schedstat_inc(sd, lb_failed[idle]);
++ sd->nr_balance_failed++;
++
++ if (unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2)) {
++
++ spin_lock_irqsave(&busiest->lock, flags);
++
++ /* don't kick the migration_thread, if the curr
++ * task on busiest cpu can't be moved to this_cpu
++ */
++ if (!cpu_isset(this_cpu, busiest->curr->cpus_allowed)) {
++ spin_unlock_irqrestore(&busiest->lock, flags);
++ all_pinned = 1;
++ goto out_one_pinned;
++ }
++
++ if (!busiest->active_balance) {
++ busiest->active_balance = 1;
++ busiest->push_cpu = this_cpu;
++ active_balance = 1;
++ }
++ spin_unlock_irqrestore(&busiest->lock, flags);
++ if (active_balance)
++ wake_up_process(busiest->migration_thread);
++
++ /*
++ * We've kicked active balancing, reset the failure
++ * counter.
++ */
++ sd->nr_balance_failed = sd->cache_nice_tries+1;
++ }
++ } else
++ sd->nr_balance_failed = 0;
++
++ if (likely(!active_balance)) {
++ /* We were unbalanced, so reset the balancing interval */
++ sd->balance_interval = sd->min_interval;
++ } else {
++ /*
++ * If we've begun active balancing, start to back off. This
++ * case may not be covered by the all_pinned logic if there
++ * is only 1 task on the busy runqueue (because we don't call
++ * move_tasks).
++ */
++ if (sd->balance_interval < sd->max_interval)
++ sd->balance_interval *= 2;
++ }
++
++ if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ ld_moved = -1;
++
++ goto out;
++
++out_balanced:
++ schedstat_inc(sd, lb_balanced[idle]);
++
++ sd->nr_balance_failed = 0;
++
++out_one_pinned:
++ /* tune up the balancing interval */
++ if ((all_pinned && sd->balance_interval < MAX_PINNED_INTERVAL) ||
++ (sd->balance_interval < sd->max_interval))
++ sd->balance_interval *= 2;
++
++ if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ ld_moved = -1;
++ else
++ ld_moved = 0;
++out:
++ if (ld_moved)
++ update_shares(sd);
++ return ld_moved;
++}
++
++/*
++ * Check this_cpu to ensure it is balanced within domain. Attempt to move
++ * tasks if there is an imbalance.
++ *
++ * Called from schedule when this_rq is about to become idle (CPU_NEWLY_IDLE).
++ * this_rq is locked.
++ */
++static int
++load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd,
++ cpumask_t *cpus)
++{
++ struct sched_group *group;
++ struct rq *busiest = NULL;
++ unsigned long imbalance;
++ int ld_moved = 0;
++ int sd_idle = 0;
++ int all_pinned = 0;
++
++ cpus_setall(*cpus);
++
++ /*
++ * When power savings policy is enabled for the parent domain, idle
++ * sibling can pick up load irrespective of busy siblings. In this case,
++ * let the state of idle sibling percolate up as IDLE, instead of
++ * portraying it as CPU_NOT_IDLE.
++ */
++ if (sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ sd_idle = 1;
++
++ schedstat_inc(sd, lb_count[CPU_NEWLY_IDLE]);
++redo:
++ update_shares_locked(this_rq, sd);
++ group = find_busiest_group(sd, this_cpu, &imbalance, CPU_NEWLY_IDLE,
++ &sd_idle, cpus, NULL);
++ if (!group) {
++ schedstat_inc(sd, lb_nobusyg[CPU_NEWLY_IDLE]);
++ goto out_balanced;
++ }
++
++ busiest = find_busiest_queue(group, CPU_NEWLY_IDLE, imbalance, cpus);
++ if (!busiest) {
++ schedstat_inc(sd, lb_nobusyq[CPU_NEWLY_IDLE]);
++ goto out_balanced;
++ }
++
++ BUG_ON(busiest == this_rq);
++
++ schedstat_add(sd, lb_imbalance[CPU_NEWLY_IDLE], imbalance);
++
++ ld_moved = 0;
++ if (busiest->nr_running > 1) {
++ /* Attempt to move tasks */
++ double_lock_balance(this_rq, busiest);
++ /* this_rq->clock is already updated */
++ update_rq_clock(busiest);
++ ld_moved = move_tasks(this_rq, this_cpu, busiest,
++ imbalance, sd, CPU_NEWLY_IDLE,
++ &all_pinned);
++ double_unlock_balance(this_rq, busiest);
++
++ if (unlikely(all_pinned)) {
++ cpu_clear(cpu_of(busiest), *cpus);
++ if (!cpus_empty(*cpus))
++ goto redo;
++ }
++ }
++
++ if (!ld_moved) {
++ schedstat_inc(sd, lb_failed[CPU_NEWLY_IDLE]);
++ if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ return -1;
++ } else
++ sd->nr_balance_failed = 0;
++
++ update_shares_locked(this_rq, sd);
++ return ld_moved;
++
++out_balanced:
++ schedstat_inc(sd, lb_balanced[CPU_NEWLY_IDLE]);
++ if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
++ !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
++ return -1;
++ sd->nr_balance_failed = 0;
++
++ return 0;
++}
++
++/*
++ * idle_balance is called by schedule() if this_cpu is about to become
++ * idle. Attempts to pull tasks from other CPUs.
++ */
++static void idle_balance(int this_cpu, struct rq *this_rq)
++{
++ struct sched_domain *sd;
++ int pulled_task = -1;
++ unsigned long next_balance = jiffies + HZ;
++ cpumask_t tmpmask;
++
++ for_each_domain(this_cpu, sd) {
++ unsigned long interval;
++
++ if (!(sd->flags & SD_LOAD_BALANCE))
++ continue;
++
++ if (sd->flags & SD_BALANCE_NEWIDLE)
++ /* If we've pulled tasks over stop searching: */
++ pulled_task = load_balance_newidle(this_cpu, this_rq,
++ sd, &tmpmask);
++
++ interval = msecs_to_jiffies(sd->balance_interval);
++ if (time_after(next_balance, sd->last_balance + interval))
++ next_balance = sd->last_balance + interval;
++ if (pulled_task)
++ break;
++ }
++ if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
++ /*
++ * We are going idle. next_balance may be set based on
++ * a busy processor. So reset next_balance.
++ */
++ this_rq->next_balance = next_balance;
++ }
++}
++
++/*
++ * active_load_balance is run by migration threads. It pushes running tasks
++ * off the busiest CPU onto idle CPUs. It requires at least 1 task to be
++ * running on each physical CPU where possible, and avoids physical /
++ * logical imbalances.
++ *
++ * Called with busiest_rq locked.
++ */
++static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
++{
++ int target_cpu = busiest_rq->push_cpu;
++ struct sched_domain *sd;
++ struct rq *target_rq;
++
++ /* Is there any task to move? */
++ if (busiest_rq->nr_running <= 1)
++ return;
++
++ target_rq = cpu_rq(target_cpu);
++
++ /*
++ * This condition is "impossible", if it occurs
++ * we need to fix it. Originally reported by
++ * Bjorn Helgaas on a 128-cpu setup.
++ */
++ BUG_ON(busiest_rq == target_rq);
++
++ /* move a task from busiest_rq to target_rq */
++ double_lock_balance(busiest_rq, target_rq);
++ update_rq_clock(busiest_rq);
++ update_rq_clock(target_rq);
++
++ /* Search for an sd spanning us and the target CPU. */
++ for_each_domain(target_cpu, sd) {
++ if ((sd->flags & SD_LOAD_BALANCE) &&
++ cpu_isset(busiest_cpu, sd->span))
++ break;
++ }
++
++ if (likely(sd)) {
++ schedstat_inc(sd, alb_count);
++
++ if (move_one_task(target_rq, target_cpu, busiest_rq,
++ sd, CPU_IDLE))
++ schedstat_inc(sd, alb_pushed);
++ else
++ schedstat_inc(sd, alb_failed);
++ }
++ double_unlock_balance(busiest_rq, target_rq);
++}
++
++#ifdef CONFIG_NO_HZ
++static struct {
++ atomic_t load_balancer;
++ cpumask_t cpu_mask;
++} nohz ____cacheline_aligned = {
++ .load_balancer = ATOMIC_INIT(-1),
++ .cpu_mask = CPU_MASK_NONE,
++};
++
++/*
++ * This routine will try to nominate the ilb (idle load balancing)
++ * owner among the cpus whose ticks are stopped. ilb owner will do the idle
++ * load balancing on behalf of all those cpus. If all the cpus in the system
++ * go into this tickless mode, then there will be no ilb owner (as there is
++ * no need for one) and all the cpus will sleep till the next wakeup event
++ * arrives...
++ *
++ * For the ilb owner, tick is not stopped. And this tick will be used
++ * for idle load balancing. ilb owner will still be part of
++ * nohz.cpu_mask..
++ *
++ * While stopping the tick, this cpu will become the ilb owner if there
++ * is no other owner. And will be the owner till that cpu becomes busy
++ * or if all cpus in the system stop their ticks at which point
++ * there is no need for ilb owner.
++ *
++ * When the ilb owner becomes busy, it nominates another owner, during the
++ * next busy scheduler_tick()
++ */
++int select_nohz_load_balancer(int stop_tick)
++{
++ int cpu = smp_processor_id();
++
++ if (stop_tick) {
++ cpu_set(cpu, nohz.cpu_mask);
++ cpu_rq(cpu)->in_nohz_recently = 1;
++
++ /*
++ * If we are going offline and still the leader, give up!
++ */
++ if (!cpu_active(cpu) &&
++ atomic_read(&nohz.load_balancer) == cpu) {
++ if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
++ BUG();
++ return 0;
++ }
++
++ /* time for ilb owner also to sleep */
++ if (cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
++ if (atomic_read(&nohz.load_balancer) == cpu)
++ atomic_set(&nohz.load_balancer, -1);
++ return 0;
++ }
++
++ if (atomic_read(&nohz.load_balancer) == -1) {
++ /* make me the ilb owner */
++ if (atomic_cmpxchg(&nohz.load_balancer, -1, cpu) == -1)
++ return 1;
++ } else if (atomic_read(&nohz.load_balancer) == cpu)
++ return 1;
++ } else {
++ if (!cpu_isset(cpu, nohz.cpu_mask))
++ return 0;
++
++ cpu_clear(cpu, nohz.cpu_mask);
++
++ if (atomic_read(&nohz.load_balancer) == cpu)
++ if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
++ BUG();
++ }
++ return 0;
++}
++#endif
++
++static DEFINE_SPINLOCK(balancing);
++
++/*
++ * It checks each scheduling domain to see if it is due to be balanced,
++ * and initiates a balancing operation if so.
++ *
++ * Balancing parameters are set up in arch_init_sched_domains.
++ */
++static void rebalance_domains(int cpu, enum cpu_idle_type idle)
++{
++ int balance = 1;
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long interval;
++ struct sched_domain *sd;
++ /* Earliest time when we have to do rebalance again */
++ unsigned long next_balance = jiffies + 60*HZ;
++ int update_next_balance = 0;
++ int need_serialize;
++ cpumask_t tmp;
++
++ for_each_domain(cpu, sd) {
++ if (!(sd->flags & SD_LOAD_BALANCE))
++ continue;
++
++ interval = sd->balance_interval;
++ if (idle != CPU_IDLE)
++ interval *= sd->busy_factor;
++
++ /* scale ms to jiffies */
++ interval = msecs_to_jiffies(interval);
++ if (unlikely(!interval))
++ interval = 1;
++ if (interval > HZ*NR_CPUS/10)
++ interval = HZ*NR_CPUS/10;
++
++ need_serialize = sd->flags & SD_SERIALIZE;
++
++ if (need_serialize) {
++ if (!spin_trylock(&balancing))
++ goto out;
++ }
++
++ if (time_after_eq(jiffies, sd->last_balance + interval)) {
++ if (load_balance(cpu, rq, sd, idle, &balance, &tmp)) {
++ /*
++ * We've pulled tasks over so either we're no
++ * longer idle, or one of our SMT siblings is
++ * not idle.
++ */
++ idle = CPU_NOT_IDLE;
++ }
++ sd->last_balance = jiffies;
++ }
++ if (need_serialize)
++ spin_unlock(&balancing);
++out:
++ if (time_after(next_balance, sd->last_balance + interval)) {
++ next_balance = sd->last_balance + interval;
++ update_next_balance = 1;
++ }
++
++ /*
++ * Stop the load balance at this level. There is another
++ * CPU in our sched group which is doing load balancing more
++ * actively.
++ */
++ if (!balance)
++ break;
++ }
++
++ /*
++ * next_balance will be updated only when there is a need.
++ * When the cpu is attached to null domain for ex, it will not be
++ * updated.
++ */
++ if (likely(update_next_balance))
++ rq->next_balance = next_balance;
++}
++
++/*
++ * run_rebalance_domains is triggered when needed from the scheduler tick.
++ * In CONFIG_NO_HZ case, the idle load balance owner will do the
++ * rebalancing for all the cpus for whom scheduler ticks are stopped.
++ */
++static void run_rebalance_domains(struct softirq_action *h)
++{
++ int this_cpu = smp_processor_id();
++ struct rq *this_rq = cpu_rq(this_cpu);
++ enum cpu_idle_type idle = this_rq->idle_at_tick ?
++ CPU_IDLE : CPU_NOT_IDLE;
++
++ rebalance_domains(this_cpu, idle);
++
++#ifdef CONFIG_NO_HZ
++ /*
++ * If this cpu is the owner for idle load balancing, then do the
++ * balancing on behalf of the other idle cpus whose ticks are
++ * stopped.
++ */
++ if (this_rq->idle_at_tick &&
++ atomic_read(&nohz.load_balancer) == this_cpu) {
++ cpumask_t cpus = nohz.cpu_mask;
++ struct rq *rq;
++ int balance_cpu;
++
++ cpu_clear(this_cpu, cpus);
++ for_each_cpu_mask_nr(balance_cpu, cpus) {
++ /*
++ * If this cpu gets work to do, stop the load balancing
++ * work being done for other cpus. Next load
++ * balancing owner will pick it up.
++ */
++ if (need_resched())
++ break;
++
++ rebalance_domains(balance_cpu, CPU_IDLE);
++
++ rq = cpu_rq(balance_cpu);
++ if (time_after(this_rq->next_balance, rq->next_balance))
++ this_rq->next_balance = rq->next_balance;
++ }
++ }
++#endif
++}
++
++/*
++ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
++ *
++ * In case of CONFIG_NO_HZ, this is the place where we nominate a new
++ * idle load balancing owner or decide to stop the periodic load balancing,
++ * if the whole system is idle.
++ */
++static inline void trigger_load_balance(struct rq *rq, int cpu)
++{
++#ifdef CONFIG_NO_HZ
++ /*
++ * If we were in the nohz mode recently and busy at the current
++ * scheduler tick, then check if we need to nominate new idle
++ * load balancer.
++ */
++ if (rq->in_nohz_recently && !rq->idle_at_tick) {
++ rq->in_nohz_recently = 0;
++
++ if (atomic_read(&nohz.load_balancer) == cpu) {
++ cpu_clear(cpu, nohz.cpu_mask);
++ atomic_set(&nohz.load_balancer, -1);
++ }
++
++ if (atomic_read(&nohz.load_balancer) == -1) {
++ /*
++ * simple selection for now: Nominate the
++ * first cpu in the nohz list to be the next
++ * ilb owner.
++ *
++ * TBD: Traverse the sched domains and nominate
++ * the nearest cpu in the nohz.cpu_mask.
++ */
++ int ilb = first_cpu(nohz.cpu_mask);
++
++ if (ilb < nr_cpu_ids)
++ resched_cpu(ilb);
++ }
++ }
++
++ /*
++ * If this cpu is idle and doing idle load balancing for all the
++ * cpus with ticks stopped, is it time for that to stop?
++ */
++ if (rq->idle_at_tick && atomic_read(&nohz.load_balancer) == cpu &&
++ cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
++ resched_cpu(cpu);
++ return;
++ }
++
++ /*
++ * If this cpu is idle and the idle load balancing is done by
++ * someone else, then no need raise the SCHED_SOFTIRQ
++ */
++ if (rq->idle_at_tick && atomic_read(&nohz.load_balancer) != cpu &&
++ cpu_isset(cpu, nohz.cpu_mask))
++ return;
++#endif
++ if (time_after_eq(jiffies, rq->next_balance))
++ raise_softirq(SCHED_SOFTIRQ);
++}
++
++#else /* CONFIG_SMP */
++
++/*
++ * on UP we do not need to balance between CPUs:
++ */
++static inline void idle_balance(int cpu, struct rq *rq)
++{
++}
++
++#endif
++
++DEFINE_PER_CPU(struct kernel_stat, kstat);
++
++EXPORT_PER_CPU_SYMBOL(kstat);
++
++/*
++ * Return p->sum_exec_runtime plus any more ns on the sched_clock
++ * that have not yet been banked in case the task is currently running.
++ */
++unsigned long long task_sched_runtime(struct task_struct *p)
++{
++ unsigned long flags;
++ u64 ns, delta_exec;
++ struct rq *rq;
++
++ rq = task_rq_lock(p, &flags);
++ ns = p->se.sum_exec_runtime;
++ if (task_current(rq, p)) {
++ update_rq_clock(rq);
++ delta_exec = rq->clock - p->se.exec_start;
++ if ((s64)delta_exec > 0)
++ ns += delta_exec;
++ }
++ task_rq_unlock(rq, &flags);
++
++ return ns;
++}
++
++/*
++ * Account user cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @cputime: the cpu time spent in user space since the last update
++ */
++void account_user_time(struct task_struct *p, cputime_t cputime)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ struct vx_info *vxi = p->vx_info; /* p is _always_ current */
++ cputime64_t tmp;
++ int nice = (TASK_NICE(p) > 0);
++
++ p->utime = cputime_add(p->utime, cputime);
++ vx_account_user(vxi, cputime, nice);
++
++ /* Add user time to cpustat. */
++ tmp = cputime_to_cputime64(cputime);
++ if (nice)
++ cpustat->nice = cputime64_add(cpustat->nice, tmp);
++ else
++ cpustat->user = cputime64_add(cpustat->user, tmp);
++ /* Account for user time used */
++ acct_update_integrals(p);
++}
++
++/*
++ * Account guest cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @cputime: the cpu time spent in virtual machine since the last update
++ */
++static void account_guest_time(struct task_struct *p, cputime_t cputime)
++{
++ cputime64_t tmp;
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++
++ tmp = cputime_to_cputime64(cputime);
++
++ p->utime = cputime_add(p->utime, cputime);
++ p->gtime = cputime_add(p->gtime, cputime);
++
++ cpustat->user = cputime64_add(cpustat->user, tmp);
++ cpustat->guest = cputime64_add(cpustat->guest, tmp);
++}
++
++/*
++ * Account scaled user cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @cputime: the cpu time spent in user space since the last update
++ */
++void account_user_time_scaled(struct task_struct *p, cputime_t cputime)
++{
++ p->utimescaled = cputime_add(p->utimescaled, cputime);
++}
++
++/*
++ * Account system cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @hardirq_offset: the offset to subtract from hardirq_count()
++ * @cputime: the cpu time spent in kernel space since the last update
++ */
++void account_system_time(struct task_struct *p, int hardirq_offset,
++ cputime_t cputime)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ struct vx_info *vxi = p->vx_info; /* p is _always_ current */
++ struct rq *rq = this_rq();
++ cputime64_t tmp;
++
++ if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) {
++ account_guest_time(p, cputime);
++ return;
++ }
++
++ p->stime = cputime_add(p->stime, cputime);
++ vx_account_system(vxi, cputime, (p == rq->idle));
++
++ /* Add system time to cpustat. */
++ tmp = cputime_to_cputime64(cputime);
++ if (hardirq_count() - hardirq_offset)
++ cpustat->irq = cputime64_add(cpustat->irq, tmp);
++ else if (softirq_count())
++ cpustat->softirq = cputime64_add(cpustat->softirq, tmp);
++ else if (p != rq->idle)
++ cpustat->system = cputime64_add(cpustat->system, tmp);
++ else if (atomic_read(&rq->nr_iowait) > 0)
++ cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
++ else
++ cpustat->idle = cputime64_add(cpustat->idle, tmp);
++ /* Account for system time used */
++ acct_update_integrals(p);
++}
++
++/*
++ * Account scaled system cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @hardirq_offset: the offset to subtract from hardirq_count()
++ * @cputime: the cpu time spent in kernel space since the last update
++ */
++void account_system_time_scaled(struct task_struct *p, cputime_t cputime)
++{
++ p->stimescaled = cputime_add(p->stimescaled, cputime);
++}
++
++/*
++ * Account for involuntary wait time.
++ * @p: the process from which the cpu time has been stolen
++ * @steal: the cpu time spent in involuntary wait
++ */
++void account_steal_time(struct task_struct *p, cputime_t steal)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime64_t tmp = cputime_to_cputime64(steal);
++ struct rq *rq = this_rq();
++
++ if (p == rq->idle) {
++ p->stime = cputime_add(p->stime, steal);
++ if (atomic_read(&rq->nr_iowait) > 0)
++ cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
++ else
++ cpustat->idle = cputime64_add(cpustat->idle, tmp);
++ } else
++ cpustat->steal = cputime64_add(cpustat->steal, tmp);
++}
++
++/*
++ * Use precise platform statistics if available:
++ */
++#ifdef CONFIG_VIRT_CPU_ACCOUNTING
++cputime_t task_utime(struct task_struct *p)
++{
++ return p->utime;
++}
++
++cputime_t task_stime(struct task_struct *p)
++{
++ return p->stime;
++}
++#else
++cputime_t task_utime(struct task_struct *p)
++{
++ clock_t utime = cputime_to_clock_t(p->utime),
++ total = utime + cputime_to_clock_t(p->stime);
++ u64 temp;
++
++ /*
++ * Use CFS's precise accounting:
++ */
++ temp = (u64)nsec_to_clock_t(p->se.sum_exec_runtime);
++
++ if (total) {
++ temp *= utime;
++ do_div(temp, total);
++ }
++ utime = (clock_t)temp;
++
++ p->prev_utime = max(p->prev_utime, clock_t_to_cputime(utime));
++ return p->prev_utime;
++}
++
++cputime_t task_stime(struct task_struct *p)
++{
++ clock_t stime;
++
++ /*
++ * Use CFS's precise accounting. (we subtract utime from
++ * the total, to make sure the total observed by userspace
++ * grows monotonically - apps rely on that):
++ */
++ stime = nsec_to_clock_t(p->se.sum_exec_runtime) -
++ cputime_to_clock_t(task_utime(p));
++
++ if (stime >= 0)
++ p->prev_stime = max(p->prev_stime, clock_t_to_cputime(stime));
++
++ return p->prev_stime;
++}
++#endif
++
++inline cputime_t task_gtime(struct task_struct *p)
++{
++ return p->gtime;
++}
++
++/*
++ * This function gets called by the timer code, with HZ frequency.
++ * We call it with interrupts disabled.
++ *
++ * It also gets called by the fork code, when changing the parent's
++ * timeslices.
++ */
++void scheduler_tick(void)
++{
++ int cpu = smp_processor_id();
++ struct rq *rq = cpu_rq(cpu);
++ struct task_struct *curr = rq->curr;
++
++ sched_clock_tick();
++
++ spin_lock(&rq->lock);
++ update_rq_clock(rq);
++ update_cpu_load(rq);
++ curr->sched_class->task_tick(rq, curr, 0);
++ spin_unlock(&rq->lock);
++
++#ifdef CONFIG_SMP
++ rq->idle_at_tick = idle_cpu(cpu);
++ trigger_load_balance(rq, cpu);
++#endif
++}
++
++#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
++ defined(CONFIG_PREEMPT_TRACER))
++
++static inline unsigned long get_parent_ip(unsigned long addr)
++{
++ if (in_lock_functions(addr)) {
++ addr = CALLER_ADDR2;
++ if (in_lock_functions(addr))
++ addr = CALLER_ADDR3;
++ }
++ return addr;
++}
++
++void __kprobes add_preempt_count(int val)
++{
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Underflow?
++ */
++ if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0)))
++ return;
++#endif
++ preempt_count() += val;
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Spinlock count overflowing soon?
++ */
++ DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
++ PREEMPT_MASK - 10);
++#endif
++ if (preempt_count() == val)
++ trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
++}
++EXPORT_SYMBOL(add_preempt_count);
++
++void __kprobes sub_preempt_count(int val)
++{
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Underflow?
++ */
++ if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
++ return;
++ /*
++ * Is the spinlock portion underflowing?
++ */
++ if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) &&
++ !(preempt_count() & PREEMPT_MASK)))
++ return;
++#endif
++
++ if (preempt_count() == val)
++ trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
++ preempt_count() -= val;
++}
++EXPORT_SYMBOL(sub_preempt_count);
++
++#endif
++
++/*
++ * Print scheduling while atomic bug:
++ */
++static noinline void __schedule_bug(struct task_struct *prev)
++{
++ struct pt_regs *regs = get_irq_regs();
++
++ printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
++ prev->comm, prev->pid, preempt_count());
++
++ debug_show_held_locks(prev);
++ print_modules();
++ if (irqs_disabled())
++ print_irqtrace_events(prev);
++
++ if (regs)
++ show_regs(regs);
++ else
++ dump_stack();
++}
++
++/*
++ * Various schedule()-time debugging checks and statistics:
++ */
++static inline void schedule_debug(struct task_struct *prev)
++{
++ /*
++ * Test if we are atomic. Since do_exit() needs to call into
++ * schedule() atomically, we ignore that path for now.
++ * Otherwise, whine if we are scheduling when we should not be.
++ */
++ if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
++ __schedule_bug(prev);
++
++ profile_hit(SCHED_PROFILING, __builtin_return_address(0));
++
++ schedstat_inc(this_rq(), sched_count);
++#ifdef CONFIG_SCHEDSTATS
++ if (unlikely(prev->lock_depth >= 0)) {
++ schedstat_inc(this_rq(), bkl_count);
++ schedstat_inc(prev, sched_info.bkl_count);
++ }
++#endif
++}
++
++/*
++ * Pick up the highest-prio task:
++ */
++static inline struct task_struct *
++pick_next_task(struct rq *rq, struct task_struct *prev)
++{
++ const struct sched_class *class;
++ struct task_struct *p;
++
++ /*
++ * Optimization: we know that if all tasks are in
++ * the fair class we can call that function directly:
++ */
++ if (likely(rq->nr_running == rq->cfs.nr_running)) {
++ p = fair_sched_class.pick_next_task(rq);
++ if (likely(p))
++ return p;
++ }
++
++ class = sched_class_highest;
++ for ( ; ; ) {
++ p = class->pick_next_task(rq);
++ if (p)
++ return p;
++ /*
++ * Will never be NULL as the idle class always
++ * returns a non-NULL p:
++ */
++ class = class->next;
++ }
++}
++
++void (*rec_event)(void *,unsigned int) = NULL;
++EXPORT_SYMBOL(rec_event);
++#ifdef CONFIG_CHOPSTIX
++
++struct event_spec {
++ unsigned long pc;
++ unsigned long dcookie;
++ unsigned int count;
++ unsigned int reason;
++};
++
++/* To support safe calling from asm */
++asmlinkage void rec_event_asm (struct event *event_signature_in, unsigned int count) {
++ struct pt_regs *regs;
++ struct event_spec *es = event_signature_in->event_data;
++ regs = task_pt_regs(current);
++ event_signature_in->task=current;
++ es->pc=regs->ip;
++ event_signature_in->count=1;
++ (*rec_event)(event_signature_in, count);
++}
++#endif
++
++/*
++ * schedule() is the main scheduler function.
++ */
++asmlinkage void __sched schedule(void)
++{
++ struct task_struct *prev, *next;
++ unsigned long *switch_count;
++ struct rq *rq;
++ int cpu;
++
++need_resched:
++ preempt_disable();
++ cpu = smp_processor_id();
++ rq = cpu_rq(cpu);
++ rcu_qsctr_inc(cpu);
++ prev = rq->curr;
++ switch_count = &prev->nivcsw;
++
++ release_kernel_lock(prev);
++need_resched_nonpreemptible:
++
++ schedule_debug(prev);
++
++ if (sched_feat(HRTICK))
++ hrtick_clear(rq);
++
++ /*
++ * Do the rq-clock update outside the rq lock:
++ */
++ local_irq_disable();
++ update_rq_clock(rq);
++ spin_lock(&rq->lock);
++ clear_tsk_need_resched(prev);
++
++ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
++ if (unlikely(signal_pending_state(prev->state, prev)))
++ prev->state = TASK_RUNNING;
++ else
++ deactivate_task(rq, prev, 1);
++ switch_count = &prev->nvcsw;
++ }
++
++#ifdef CONFIG_SMP
++ if (prev->sched_class->pre_schedule)
++ prev->sched_class->pre_schedule(rq, prev);
++#endif
++
++ if (unlikely(!rq->nr_running))
++ idle_balance(cpu, rq);
++
++ prev->sched_class->put_prev_task(rq, prev);
++ next = pick_next_task(rq, prev);
++
++ if (likely(prev != next)) {
++ sched_info_switch(prev, next);
++
++ rq->nr_switches++;
++ rq->curr = next;
++ ++*switch_count;
++
++ context_switch(rq, prev, next); /* unlocks the rq */
++ /*
++ * the context switch might have flipped the stack from under
++ * us, hence refresh the local variables.
++ */
++ cpu = smp_processor_id();
++ rq = cpu_rq(cpu);
++ } else
++ spin_unlock_irq(&rq->lock);
++
++ if (unlikely(reacquire_kernel_lock(current) < 0))
++ goto need_resched_nonpreemptible;
++
++ preempt_enable_no_resched();
++ if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
++ goto need_resched;
++}
++EXPORT_SYMBOL(schedule);
++
++#ifdef CONFIG_PREEMPT
++/*
++ * this is the entry point to schedule() from in-kernel preemption
++ * off of preempt_enable. Kernel preemptions off return from interrupt
++ * occur there and call schedule directly.
++ */
++asmlinkage void __sched preempt_schedule(void)
++{
++ struct thread_info *ti = current_thread_info();
++
++ /*
++ * If there is a non-zero preempt_count or interrupts are disabled,
++ * we do not want to preempt the current task. Just return..
++ */
++ if (likely(ti->preempt_count || irqs_disabled()))
++ return;
++
++ do {
++ add_preempt_count(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count(PREEMPT_ACTIVE);
++
++ /*
++ * Check again in case we missed a preemption opportunity
++ * between schedule and now.
++ */
++ barrier();
++ } while (unlikely(test_thread_flag(TIF_NEED_RESCHED)));
++}
++EXPORT_SYMBOL(preempt_schedule);
++
++/*
++ * this is the entry point to schedule() from kernel preemption
++ * off of irq context.
++ * Note, that this is called and return with irqs disabled. This will
++ * protect us against recursive calling from irq.
++ */
++asmlinkage void __sched preempt_schedule_irq(void)
++{
++ struct thread_info *ti = current_thread_info();
++
++ /* Catch callers which need to be fixed */
++ BUG_ON(ti->preempt_count || !irqs_disabled());
++
++ do {
++ add_preempt_count(PREEMPT_ACTIVE);
++ local_irq_enable();
++ schedule();
++ local_irq_disable();
++ sub_preempt_count(PREEMPT_ACTIVE);
++
++ /*
++ * Check again in case we missed a preemption opportunity
++ * between schedule and now.
++ */
++ barrier();
++ } while (unlikely(test_thread_flag(TIF_NEED_RESCHED)));
++}
++
++#endif /* CONFIG_PREEMPT */
++
++int default_wake_function(wait_queue_t *curr, unsigned mode, int sync,
++ void *key)
++{
++ return try_to_wake_up(curr->private, mode, sync);
++}
++EXPORT_SYMBOL(default_wake_function);
++
++/*
++ * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just
++ * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve
++ * number) then we wake all the non-exclusive tasks and one exclusive task.
++ *
++ * There are circumstances in which we can try to wake a task which has already
++ * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns
++ * zero in this (rare) case, and we handle it by continuing to scan the queue.
++ */
++static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, int sync, void *key)
++{
++ wait_queue_t *curr, *next;
++
++ list_for_each_entry_safe(curr, next, &q->task_list, task_list) {
++ unsigned flags = curr->flags;
++
++ if (curr->func(curr, mode, sync, key) &&
++ (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
++ break;
++ }
++}
++
++/**
++ * __wake_up - wake up threads blocked on a waitqueue.
++ * @q: the waitqueue
++ * @mode: which threads
++ * @nr_exclusive: how many wake-one or wake-many threads to wake up
++ * @key: is directly passed to the wakeup function
++ */
++void __wake_up(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, void *key)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&q->lock, flags);
++ __wake_up_common(q, mode, nr_exclusive, 0, key);
++ spin_unlock_irqrestore(&q->lock, flags);
++}
++EXPORT_SYMBOL(__wake_up);
++
++/*
++ * Same as __wake_up but called with the spinlock in wait_queue_head_t held.
++ */
++void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
++{
++ __wake_up_common(q, mode, 1, 0, NULL);
++}
++
++/**
++ * __wake_up_sync - wake up threads blocked on a waitqueue.
++ * @q: the waitqueue
++ * @mode: which threads
++ * @nr_exclusive: how many wake-one or wake-many threads to wake up
++ *
++ * The sync wakeup differs that the waker knows that it will schedule
++ * away soon, so while the target thread will be woken up, it will not
++ * be migrated to another CPU - ie. the two threads are 'synchronized'
++ * with each other. This can prevent needless bouncing between CPUs.
++ *
++ * On UP it can prevent extra preemption.
++ */
++void
++__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
++{
++ unsigned long flags;
++ int sync = 1;
++
++ if (unlikely(!q))
++ return;
++
++ if (unlikely(!nr_exclusive))
++ sync = 0;
++
++ spin_lock_irqsave(&q->lock, flags);
++ __wake_up_common(q, mode, nr_exclusive, sync, NULL);
++ spin_unlock_irqrestore(&q->lock, flags);
++}
++EXPORT_SYMBOL_GPL(__wake_up_sync); /* For internal use only */
++
++void complete(struct completion *x)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ x->done++;
++ __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++}
++EXPORT_SYMBOL(complete);
++
++void complete_all(struct completion *x)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ x->done += UINT_MAX/2;
++ __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++}
++EXPORT_SYMBOL(complete_all);
++
++static inline long __sched
++do_wait_for_common(struct completion *x, long timeout, int state)
++{
++ if (!x->done) {
++ DECLARE_WAITQUEUE(wait, current);
++
++ wait.flags |= WQ_FLAG_EXCLUSIVE;
++ __add_wait_queue_tail(&x->wait, &wait);
++ do {
++ if ((state == TASK_INTERRUPTIBLE &&
++ signal_pending(current)) ||
++ (state == TASK_KILLABLE &&
++ fatal_signal_pending(current))) {
++ timeout = -ERESTARTSYS;
++ break;
++ }
++ __set_current_state(state);
++ spin_unlock_irq(&x->wait.lock);
++ timeout = schedule_timeout(timeout);
++ spin_lock_irq(&x->wait.lock);
++ } while (!x->done && timeout);
++ __remove_wait_queue(&x->wait, &wait);
++ if (!x->done)
++ return timeout;
++ }
++ x->done--;
++ return timeout ?: 1;
++}
++
++static long __sched
++wait_for_common(struct completion *x, long timeout, int state)
++{
++ might_sleep();
++
++ spin_lock_irq(&x->wait.lock);
++ timeout = do_wait_for_common(x, timeout, state);
++ spin_unlock_irq(&x->wait.lock);
++ return timeout;
++}
++
++void __sched wait_for_completion(struct completion *x)
++{
++ wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion);
++
++unsigned long __sched
++wait_for_completion_timeout(struct completion *x, unsigned long timeout)
++{
++ return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion_timeout);
++
++int __sched wait_for_completion_interruptible(struct completion *x)
++{
++ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE);
++ if (t == -ERESTARTSYS)
++ return t;
++ return 0;
++}
++EXPORT_SYMBOL(wait_for_completion_interruptible);
++
++unsigned long __sched
++wait_for_completion_interruptible_timeout(struct completion *x,
++ unsigned long timeout)
++{
++ return wait_for_common(x, timeout, TASK_INTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
++
++int __sched wait_for_completion_killable(struct completion *x)
++{
++ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
++ if (t == -ERESTARTSYS)
++ return t;
++ return 0;
++}
++EXPORT_SYMBOL(wait_for_completion_killable);
++
++/**
++ * try_wait_for_completion - try to decrement a completion without blocking
++ * @x: completion structure
++ *
++ * Returns: 0 if a decrement cannot be done without blocking
++ * 1 if a decrement succeeded.
++ *
++ * If a completion is being used as a counting completion,
++ * attempt to decrement the counter without blocking. This
++ * enables us to avoid waiting if the resource the completion
++ * is protecting is not available.
++ */
++bool try_wait_for_completion(struct completion *x)
++{
++ int ret = 1;
++
++ spin_lock_irq(&x->wait.lock);
++ if (!x->done)
++ ret = 0;
++ else
++ x->done--;
++ spin_unlock_irq(&x->wait.lock);
++ return ret;
++}
++EXPORT_SYMBOL(try_wait_for_completion);
++
++/**
++ * completion_done - Test to see if a completion has any waiters
++ * @x: completion structure
++ *
++ * Returns: 0 if there are waiters (wait_for_completion() in progress)
++ * 1 if there are no waiters.
++ *
++ */
++bool completion_done(struct completion *x)
++{
++ int ret = 1;
++
++ spin_lock_irq(&x->wait.lock);
++ if (!x->done)
++ ret = 0;
++ spin_unlock_irq(&x->wait.lock);
++ return ret;
++}
++EXPORT_SYMBOL(completion_done);
++
++static long __sched
++sleep_on_common(wait_queue_head_t *q, int state, long timeout)
++{
++ unsigned long flags;
++ wait_queue_t wait;
++
++ init_waitqueue_entry(&wait, current);
++
++ __set_current_state(state);
++
++ spin_lock_irqsave(&q->lock, flags);
++ __add_wait_queue(q, &wait);
++ spin_unlock(&q->lock);
++ timeout = schedule_timeout(timeout);
++ spin_lock_irq(&q->lock);
++ __remove_wait_queue(q, &wait);
++ spin_unlock_irqrestore(&q->lock, flags);
++
++ return timeout;
++}
++
++void __sched interruptible_sleep_on(wait_queue_head_t *q)
++{
++ sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
++}
++EXPORT_SYMBOL(interruptible_sleep_on);
++
++long __sched
++interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
++{
++ return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout);
++}
++EXPORT_SYMBOL(interruptible_sleep_on_timeout);
++
++void __sched sleep_on(wait_queue_head_t *q)
++{
++ sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
++}
++EXPORT_SYMBOL(sleep_on);
++
++long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
++{
++ return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout);
++}
++EXPORT_SYMBOL(sleep_on_timeout);
++
++#ifdef CONFIG_RT_MUTEXES
++
++/*
++ * rt_mutex_setprio - set the current priority of a task
++ * @p: task
++ * @prio: prio value (kernel-internal form)
++ *
++ * This function changes the 'effective' priority of a task. It does
++ * not touch ->normal_prio like __setscheduler().
++ *
++ * Used by the rt_mutex code to implement priority inheritance logic.
++ */
++void rt_mutex_setprio(struct task_struct *p, int prio)
++{
++ unsigned long flags;
++ int oldprio, on_rq, running;
++ struct rq *rq;
++ const struct sched_class *prev_class = p->sched_class;
++
++ BUG_ON(prio < 0 || prio > MAX_PRIO);
++
++ rq = task_rq_lock(p, &flags);
++ update_rq_clock(rq);
++
++ oldprio = p->prio;
++ on_rq = p->se.on_rq;
++ running = task_current(rq, p);
++ if (on_rq)
++ dequeue_task(rq, p, 0);
++ if (running)
++ p->sched_class->put_prev_task(rq, p);
++
++ if (rt_prio(prio))
++ p->sched_class = &rt_sched_class;
++ else
++ p->sched_class = &fair_sched_class;
++
++ p->prio = prio;
++
++ if (running)
++ p->sched_class->set_curr_task(rq);
++ if (on_rq) {
++ enqueue_task(rq, p, 0);
++
++ check_class_changed(rq, p, prev_class, oldprio, running);
++ }
++ task_rq_unlock(rq, &flags);
++}
++
++#endif
++
++void set_user_nice(struct task_struct *p, long nice)
++{
++ int old_prio, delta, on_rq;
++ unsigned long flags;
++ struct rq *rq;
++
++ if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
++ return;
++ /*
++ * We have to be careful, if called from sys_setpriority(),
++ * the task might be in the middle of scheduling on another CPU.
++ */
++ rq = task_rq_lock(p, &flags);
++ update_rq_clock(rq);
++ /*
++ * The RT priorities are set via sched_setscheduler(), but we still
++ * allow the 'normal' nice value to be set - but as expected
++ * it wont have any effect on scheduling until the task is
++ * SCHED_FIFO/SCHED_RR:
++ */
++ if (task_has_rt_policy(p)) {
++ p->static_prio = NICE_TO_PRIO(nice);
++ goto out_unlock;
++ }
++ on_rq = p->se.on_rq;
++ if (on_rq)
++ dequeue_task(rq, p, 0);
++
++ p->static_prio = NICE_TO_PRIO(nice);
++ set_load_weight(p);
++ old_prio = p->prio;
++ p->prio = effective_prio(p);
++ delta = p->prio - old_prio;
++
++ if (on_rq) {
++ enqueue_task(rq, p, 0);
++ /*
++ * If the task increased its priority or is running and
++ * lowered its priority, then reschedule its CPU:
++ */
++ if (delta < 0 || (delta > 0 && task_running(rq, p)))
++ resched_task(rq->curr);
++ }
++out_unlock:
++ task_rq_unlock(rq, &flags);
++}
++EXPORT_SYMBOL(set_user_nice);
++
++/*
++ * can_nice - check if a task can reduce its nice value
++ * @p: task
++ * @nice: nice value
++ */
++int can_nice(const struct task_struct *p, const int nice)
++{
++ /* convert nice value [19,-20] to rlimit style value [1,40] */
++ int nice_rlim = 20 - nice;
++
++ return (nice_rlim <= p->signal->rlim[RLIMIT_NICE].rlim_cur ||
++ capable(CAP_SYS_NICE));
++}
++
++#ifdef __ARCH_WANT_SYS_NICE
++
++/*
++ * sys_nice - change the priority of the current process.
++ * @increment: priority increment
++ *
++ * sys_setpriority is a more generic, but much slower function that
++ * does similar things.
++ */
++SYSCALL_DEFINE1(nice, int, increment)
++{
++ long nice, retval;
++
++ /*
++ * Setpriority might change our priority at the same moment.
++ * We don't have to worry. Conceptually one call occurs first
++ * and we have a single winner.
++ */
++ if (increment < -40)
++ increment = -40;
++ if (increment > 40)
++ increment = 40;
++
++ nice = PRIO_TO_NICE(current->static_prio) + increment;
++ if (nice < -20)
++ nice = -20;
++ if (nice > 19)
++ nice = 19;
++
++ if (increment < 0 && !can_nice(current, nice))
++ return vx_flags(VXF_IGNEG_NICE, 0) ? 0 : -EPERM;
++
++ retval = security_task_setnice(current, nice);
++ if (retval)
++ return retval;
++
++ set_user_nice(current, nice);
++ return 0;
++}
++
++#endif
++
++/**
++ * task_prio - return the priority value of a given task.
++ * @p: the task in question.
++ *
++ * This is the priority value as seen by users in /proc.
++ * RT tasks are offset by -200. Normal tasks are centered
++ * around 0, value goes from -16 to +15.
++ */
++int task_prio(const struct task_struct *p)
++{
++ return p->prio - MAX_RT_PRIO;
++}
++
++/**
++ * task_nice - return the nice value of a given task.
++ * @p: the task in question.
++ */
++int task_nice(const struct task_struct *p)
++{
++ return TASK_NICE(p);
++}
++EXPORT_SYMBOL(task_nice);
++
++/**
++ * idle_cpu - is a given cpu idle currently?
++ * @cpu: the processor in question.
++ */
++int idle_cpu(int cpu)
++{
++ return cpu_curr(cpu) == cpu_rq(cpu)->idle;
++}
++
++/**
++ * idle_task - return the idle task for a given cpu.
++ * @cpu: the processor in question.
++ */
++struct task_struct *idle_task(int cpu)
++{
++ return cpu_rq(cpu)->idle;
++}
++
++/**
++ * find_process_by_pid - find a process with a matching PID value.
++ * @pid: the pid in question.
++ */
++static struct task_struct *find_process_by_pid(pid_t pid)
++{
++ return pid ? find_task_by_vpid(pid) : current;
++}
++
++/* Actually do priority change: must hold rq lock. */
++static void
++__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio)
++{
++ BUG_ON(p->se.on_rq);
++
++ p->policy = policy;
++ switch (p->policy) {
++ case SCHED_NORMAL:
++ case SCHED_BATCH:
++ case SCHED_IDLE:
++ p->sched_class = &fair_sched_class;
++ break;
++ case SCHED_FIFO:
++ case SCHED_RR:
++ p->sched_class = &rt_sched_class;
++ break;
++ }
++
++ p->rt_priority = prio;
++ p->normal_prio = normal_prio(p);
++ /* we are holding p->pi_lock already */
++ p->prio = rt_mutex_getprio(p);
++ set_load_weight(p);
++}
++
++static int __sched_setscheduler(struct task_struct *p, int policy,
++ struct sched_param *param, bool user)
++{
++ int retval, oldprio, oldpolicy = -1, on_rq, running;
++ unsigned long flags;
++ const struct sched_class *prev_class = p->sched_class;
++ struct rq *rq;
++
++ /* may grab non-irq protected spin_locks */
++ BUG_ON(in_interrupt());
++recheck:
++ /* double check policy once rq lock held */
++ if (policy < 0)
++ policy = oldpolicy = p->policy;
++ else if (policy != SCHED_FIFO && policy != SCHED_RR &&
++ policy != SCHED_NORMAL && policy != SCHED_BATCH &&
++ policy != SCHED_IDLE)
++ return -EINVAL;
++ /*
++ * Valid priorities for SCHED_FIFO and SCHED_RR are
++ * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
++ * SCHED_BATCH and SCHED_IDLE is 0.
++ */
++ if (param->sched_priority < 0 ||
++ (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) ||
++ (!p->mm && param->sched_priority > MAX_RT_PRIO-1))
++ return -EINVAL;
++ if (rt_policy(policy) != (param->sched_priority != 0))
++ return -EINVAL;
++
++ /*
++ * Allow unprivileged RT tasks to decrease priority:
++ */
++ if (user && !capable(CAP_SYS_NICE)) {
++ if (rt_policy(policy)) {
++ unsigned long rlim_rtprio;
++
++ if (!lock_task_sighand(p, &flags))
++ return -ESRCH;
++ rlim_rtprio = p->signal->rlim[RLIMIT_RTPRIO].rlim_cur;
++ unlock_task_sighand(p, &flags);
++
++ /* can't set/change the rt policy */
++ if (policy != p->policy && !rlim_rtprio)
++ return -EPERM;
++
++ /* can't increase priority */
++ if (param->sched_priority > p->rt_priority &&
++ param->sched_priority > rlim_rtprio)
++ return -EPERM;
++ }
++ /*
++ * Like positive nice levels, dont allow tasks to
++ * move out of SCHED_IDLE either:
++ */
++ if (p->policy == SCHED_IDLE && policy != SCHED_IDLE)
++ return -EPERM;
++
++ /* can't change other user's priorities */
++ if ((current->euid != p->euid) &&
++ (current->euid != p->uid))
++ return -EPERM;
++ }
++
++ if (user) {
++#ifdef CONFIG_RT_GROUP_SCHED
++ /*
++ * Do not allow realtime tasks into groups that have no runtime
++ * assigned.
++ */
++ if (rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
++ return -EPERM;
++#endif
++
++ retval = security_task_setscheduler(p, policy, param);
++ if (retval)
++ return retval;
++ }
++
++ /*
++ * make sure no PI-waiters arrive (or leave) while we are
++ * changing the priority of the task:
++ */
++ spin_lock_irqsave(&p->pi_lock, flags);
++ /*
++ * To be able to change p->policy safely, the apropriate
++ * runqueue lock must be held.
++ */
++ rq = __task_rq_lock(p);
++ /* recheck policy now with rq lock held */
++ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
++ policy = oldpolicy = -1;
++ __task_rq_unlock(rq);
++ spin_unlock_irqrestore(&p->pi_lock, flags);
++ goto recheck;
++ }
++ update_rq_clock(rq);
++ on_rq = p->se.on_rq;
++ running = task_current(rq, p);
++ if (on_rq)
++ deactivate_task(rq, p, 0);
++ if (running)
++ p->sched_class->put_prev_task(rq, p);
++
++ oldprio = p->prio;
++ __setscheduler(rq, p, policy, param->sched_priority);
++
++ if (running)
++ p->sched_class->set_curr_task(rq);
++ if (on_rq) {
++ activate_task(rq, p, 0);
++
++ check_class_changed(rq, p, prev_class, oldprio, running);
++ }
++ __task_rq_unlock(rq);
++ spin_unlock_irqrestore(&p->pi_lock, flags);
++
++ rt_mutex_adjust_pi(p);
++
++ return 0;
++}
++
++/**
++ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
++ * @p: the task in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ *
++ * NOTE that the task may be already dead.
++ */
++int sched_setscheduler(struct task_struct *p, int policy,
++ struct sched_param *param)
++{
++ return __sched_setscheduler(p, policy, param, true);
++}
++EXPORT_SYMBOL_GPL(sched_setscheduler);
++
++/**
++ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
++ * @p: the task in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ *
++ * Just like sched_setscheduler, only don't bother checking if the
++ * current context has permission. For example, this is needed in
++ * stop_machine(): we create temporary high priority worker threads,
++ * but our caller might not have that capability.
++ */
++int sched_setscheduler_nocheck(struct task_struct *p, int policy,
++ struct sched_param *param)
++{
++ return __sched_setscheduler(p, policy, param, false);
++}
++
++static int
++do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
++{
++ struct sched_param lparam;
++ struct task_struct *p;
++ int retval;
++
++ if (!param || pid < 0)
++ return -EINVAL;
++ if (copy_from_user(&lparam, param, sizeof(struct sched_param)))
++ return -EFAULT;
++
++ rcu_read_lock();
++ retval = -ESRCH;
++ p = find_process_by_pid(pid);
++ if (p != NULL)
++ retval = sched_setscheduler(p, policy, &lparam);
++ rcu_read_unlock();
++
++ return retval;
++}
++
++/**
++ * sys_sched_setscheduler - set/change the scheduler policy and RT priority
++ * @pid: the pid in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ */
++SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy,
++ struct sched_param __user *, param)
++{
++ /* negative values for policy are not valid */
++ if (policy < 0)
++ return -EINVAL;
++
++ return do_sched_setscheduler(pid, policy, param);
++}
++
++/**
++ * sys_sched_setparam - set/change the RT priority of a thread
++ * @pid: the pid in question.
++ * @param: structure containing the new RT priority.
++ */
++SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
++{
++ return do_sched_setscheduler(pid, -1, param);
++}
++
++/**
++ * sys_sched_getscheduler - get the policy (scheduling class) of a thread
++ * @pid: the pid in question.
++ */
++SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
++{
++ struct task_struct *p;
++ int retval;
++
++ if (pid < 0)
++ return -EINVAL;
++
++ retval = -ESRCH;
++ read_lock(&tasklist_lock);
++ p = find_process_by_pid(pid);
++ if (p) {
++ retval = security_task_getscheduler(p);
++ if (!retval)
++ retval = p->policy;
++ }
++ read_unlock(&tasklist_lock);
++ return retval;
++}
++
++/**
++ * sys_sched_getscheduler - get the RT priority of a thread
++ * @pid: the pid in question.
++ * @param: structure containing the RT priority.
++ */
++SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
++{
++ struct sched_param lp;
++ struct task_struct *p;
++ int retval;
++
++ if (!param || pid < 0)
++ return -EINVAL;
++
++ read_lock(&tasklist_lock);
++ p = find_process_by_pid(pid);
++ retval = -ESRCH;
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ lp.sched_priority = p->rt_priority;
++ read_unlock(&tasklist_lock);
++
++ /*
++ * This one might sleep, we cannot do it with a spinlock held ...
++ */
++ retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0;
++
++ return retval;
++
++out_unlock:
++ read_unlock(&tasklist_lock);
++ return retval;
++}
++
++long sched_setaffinity(pid_t pid, const cpumask_t *in_mask)
++{
++ cpumask_t cpus_allowed;
++ cpumask_t new_mask = *in_mask;
++ struct task_struct *p;
++ int retval;
++
++ get_online_cpus();
++ read_lock(&tasklist_lock);
++
++ p = find_process_by_pid(pid);
++ if (!p) {
++ read_unlock(&tasklist_lock);
++ put_online_cpus();
++ return -ESRCH;
++ }
++
++ /*
++ * It is not safe to call set_cpus_allowed with the
++ * tasklist_lock held. We will bump the task_struct's
++ * usage count and then drop tasklist_lock.
++ */
++ get_task_struct(p);
++ read_unlock(&tasklist_lock);
++
++
++ retval = -EPERM;
++ if ((current->euid != p->euid) && (current->euid != p->uid) &&
++ !capable(CAP_SYS_NICE))
++ goto out_unlock;
++
++ retval = security_task_setscheduler(p, 0, NULL);
++ if (retval)
++ goto out_unlock;
++
++ cpuset_cpus_allowed(p, &cpus_allowed);
++ cpus_and(new_mask, new_mask, cpus_allowed);
++ again:
++ retval = set_cpus_allowed_ptr(p, &new_mask);
++
++ if (!retval) {
++ cpuset_cpus_allowed(p, &cpus_allowed);
++ if (!cpus_subset(new_mask, cpus_allowed)) {
++ /*
++ * We must have raced with a concurrent cpuset
++ * update. Just reset the cpus_allowed to the
++ * cpuset's cpus_allowed
++ */
++ new_mask = cpus_allowed;
++ goto again;
++ }
++ }
++out_unlock:
++ put_task_struct(p);
++ put_online_cpus();
++ return retval;
++}
++
++static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len,
++ cpumask_t *new_mask)
++{
++ if (len < sizeof(cpumask_t)) {
++ memset(new_mask, 0, sizeof(cpumask_t));
++ } else if (len > sizeof(cpumask_t)) {
++ len = sizeof(cpumask_t);
++ }
++ return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0;
++}
++
++/**
++ * sys_sched_setaffinity - set the cpu affinity of a process
++ * @pid: pid of the process
++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
++ * @user_mask_ptr: user-space pointer to the new cpu mask
++ */
++SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len,
++ unsigned long __user *, user_mask_ptr)
++{
++ cpumask_t new_mask;
++ int retval;
++
++ retval = get_user_cpu_mask(user_mask_ptr, len, &new_mask);
++ if (retval)
++ return retval;
++
++ return sched_setaffinity(pid, &new_mask);
++}
++
++long sched_getaffinity(pid_t pid, cpumask_t *mask)
++{
++ struct task_struct *p;
++ int retval;
++
++ get_online_cpus();
++ read_lock(&tasklist_lock);
++
++ retval = -ESRCH;
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ cpus_and(*mask, p->cpus_allowed, cpu_online_map);
++
++out_unlock:
++ read_unlock(&tasklist_lock);
++ put_online_cpus();
++
++ return retval;
++}
++
++/**
++ * sys_sched_getaffinity - get the cpu affinity of a process
++ * @pid: pid of the process
++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
++ * @user_mask_ptr: user-space pointer to hold the current cpu mask
++ */
++SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,
++ unsigned long __user *, user_mask_ptr)
++{
++ int ret;
++ cpumask_t mask;
++
++ if (len < sizeof(cpumask_t))
++ return -EINVAL;
++
++ ret = sched_getaffinity(pid, &mask);
++ if (ret < 0)
++ return ret;
++
++ if (copy_to_user(user_mask_ptr, &mask, sizeof(cpumask_t)))
++ return -EFAULT;
++
++ return sizeof(cpumask_t);
++}
++
++/**
++ * sys_sched_yield - yield the current processor to other threads.
++ *
++ * This function yields the current CPU to other tasks. If there are no
++ * other threads running on this CPU then this function will return.
++ */
++SYSCALL_DEFINE0(sched_yield)
++{
++ struct rq *rq = this_rq_lock();
++
++ schedstat_inc(rq, yld_count);
++ current->sched_class->yield_task(rq);
++
++ /*
++ * Since we are going to call schedule() anyway, there's
++ * no need to preempt or enable interrupts:
++ */
++ __release(rq->lock);
++ spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
++ _raw_spin_unlock(&rq->lock);
++ preempt_enable_no_resched();
++
++ schedule();
++
++ return 0;
++}
++
++static void __cond_resched(void)
++{
++#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
++ __might_sleep(__FILE__, __LINE__);
++#endif
++ /*
++ * The BKS might be reacquired before we have dropped
++ * PREEMPT_ACTIVE, which could trigger a second
++ * cond_resched() call.
++ */
++ do {
++ add_preempt_count(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count(PREEMPT_ACTIVE);
++ } while (need_resched());
++}
++
++int __sched _cond_resched(void)
++{
++ if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
++ system_state == SYSTEM_RUNNING) {
++ __cond_resched();
++ return 1;
++ }
++ return 0;
++}
++EXPORT_SYMBOL(_cond_resched);
++
++/*
++ * cond_resched_lock() - if a reschedule is pending, drop the given lock,
++ * call schedule, and on return reacquire the lock.
++ *
++ * This works OK both with and without CONFIG_PREEMPT. We do strange low-level
++ * operations here to prevent schedule() from being called twice (once via
++ * spin_unlock(), once by hand).
++ */
++int cond_resched_lock(spinlock_t *lock)
++{
++ int resched = need_resched() && system_state == SYSTEM_RUNNING;
++ int ret = 0;
++
++ if (spin_needbreak(lock) || resched) {
++ spin_unlock(lock);
++ if (resched && need_resched())
++ __cond_resched();
++ else
++ cpu_relax();
++ ret = 1;
++ spin_lock(lock);
++ }
++ return ret;
++}
++EXPORT_SYMBOL(cond_resched_lock);
++
++int __sched cond_resched_softirq(void)
++{
++ BUG_ON(!in_softirq());
++
++ if (need_resched() && system_state == SYSTEM_RUNNING) {
++ local_bh_enable();
++ __cond_resched();
++ local_bh_disable();
++ return 1;
++ }
++ return 0;
++}
++EXPORT_SYMBOL(cond_resched_softirq);
++
++/**
++ * yield - yield the current processor to other threads.
++ *
++ * This is a shortcut for kernel-space yielding - it marks the
++ * thread runnable and calls sys_sched_yield().
++ */
++void __sched yield(void)
++{
++ set_current_state(TASK_RUNNING);
++ sys_sched_yield();
++}
++EXPORT_SYMBOL(yield);
++
++/*
++ * This task is about to go to sleep on IO. Increment rq->nr_iowait so
++ * that process accounting knows that this is a task in IO wait state.
++ *
++ * But don't do that if it is a deliberate, throttling IO wait (this task
++ * has set its backing_dev_info: the queue against which it should throttle)
++ */
++void __sched io_schedule(void)
++{
++ struct rq *rq = &__raw_get_cpu_var(runqueues);
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ schedule();
++ atomic_dec(&rq->nr_iowait);
++ delayacct_blkio_end();
++}
++EXPORT_SYMBOL(io_schedule);
++
++long __sched io_schedule_timeout(long timeout)
++{
++ struct rq *rq = &__raw_get_cpu_var(runqueues);
++ long ret;
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ ret = schedule_timeout(timeout);
++ atomic_dec(&rq->nr_iowait);
++ delayacct_blkio_end();
++ return ret;
++}
++
++/**
++ * sys_sched_get_priority_max - return maximum RT priority.
++ * @policy: scheduling class.
++ *
++ * this syscall returns the maximum rt_priority that can be used
++ * by a given scheduling class.
++ */
++SYSCALL_DEFINE1(sched_get_priority_max, int, policy)
++{
++ int ret = -EINVAL;
++
++ switch (policy) {
++ case SCHED_FIFO:
++ case SCHED_RR:
++ ret = MAX_USER_RT_PRIO-1;
++ break;
++ case SCHED_NORMAL:
++ case SCHED_BATCH:
++ case SCHED_IDLE:
++ ret = 0;
++ break;
++ }
++ return ret;
++}
++
++/**
++ * sys_sched_get_priority_min - return minimum RT priority.
++ * @policy: scheduling class.
++ *
++ * this syscall returns the minimum rt_priority that can be used
++ * by a given scheduling class.
++ */
++SYSCALL_DEFINE1(sched_get_priority_min, int, policy)
++{
++ int ret = -EINVAL;
++
++ switch (policy) {
++ case SCHED_FIFO:
++ case SCHED_RR:
++ ret = 1;
++ break;
++ case SCHED_NORMAL:
++ case SCHED_BATCH:
++ case SCHED_IDLE:
++ ret = 0;
++ }
++ return ret;
++}
++
++/**
++ * sys_sched_rr_get_interval - return the default timeslice of a process.
++ * @pid: pid of the process.
++ * @interval: userspace pointer to the timeslice value.
++ *
++ * this syscall writes the default timeslice value of a given process
++ * into the user-space timespec buffer. A value of '0' means infinity.
++ */
++SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
++ struct timespec __user *, interval)
++{
++ struct task_struct *p;
++ unsigned int time_slice;
++ int retval;
++ struct timespec t;
++
++ if (pid < 0)
++ return -EINVAL;
++
++ retval = -ESRCH;
++ read_lock(&tasklist_lock);
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ /*
++ * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER
++ * tasks that are on an otherwise idle runqueue:
++ */
++ time_slice = 0;
++ if (p->policy == SCHED_RR) {
++ time_slice = DEF_TIMESLICE;
++ } else if (p->policy != SCHED_FIFO) {
++ struct sched_entity *se = &p->se;
++ unsigned long flags;
++ struct rq *rq;
++
++ rq = task_rq_lock(p, &flags);
++ if (rq->cfs.load.weight)
++ time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
++ task_rq_unlock(rq, &flags);
++ }
++ read_unlock(&tasklist_lock);
++ jiffies_to_timespec(time_slice, &t);
++ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
++ return retval;
++
++out_unlock:
++ read_unlock(&tasklist_lock);
++ return retval;
++}
++
++static const char stat_nam[] = TASK_STATE_TO_CHAR_STR;
++
++void sched_show_task(struct task_struct *p)
++{
++ unsigned long free = 0;
++ unsigned state;
++
++ state = p->state ? __ffs(p->state) + 1 : 0;
++ printk(KERN_INFO "%-13.13s %c", p->comm,
++ state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?');
++#if BITS_PER_LONG == 32
++ if (state == TASK_RUNNING)
++ printk(KERN_CONT " running ");
++ else
++ printk(KERN_CONT " %08lx ", thread_saved_pc(p));
++#else
++ if (state == TASK_RUNNING)
++ printk(KERN_CONT " running task ");
++ else
++ printk(KERN_CONT " %016lx ", thread_saved_pc(p));
++#endif
++#ifdef CONFIG_DEBUG_STACK_USAGE
++ {
++ unsigned long *n = end_of_stack(p);
++ while (!*n)
++ n++;
++ free = (unsigned long)n - (unsigned long)end_of_stack(p);
++ }
++#endif
++ printk(KERN_CONT "%5lu %5d %6d\n", free,
++ task_pid_nr(p), task_pid_nr(p->real_parent));
++
++ show_stack(p, NULL);
++}
++
++void show_state_filter(unsigned long state_filter)
++{
++ struct task_struct *g, *p;
++
++#if BITS_PER_LONG == 32
++ printk(KERN_INFO
++ " task PC stack pid father\n");
++#else
++ printk(KERN_INFO
++ " task PC stack pid father\n");
++#endif
++ read_lock(&tasklist_lock);
++ do_each_thread(g, p) {
++ /*
++ * reset the NMI-timeout, listing all files on a slow
++ * console might take alot of time:
++ */
++ touch_nmi_watchdog();
++ if (!state_filter || (p->state & state_filter))
++ sched_show_task(p);
++ } while_each_thread(g, p);
++
++ touch_all_softlockup_watchdogs();
++
++#ifdef CONFIG_SCHED_DEBUG
++ sysrq_sched_debug_show();
++#endif
++ read_unlock(&tasklist_lock);
++ /*
++ * Only show locks if all tasks are dumped:
++ */
++ if (state_filter == -1)
++ debug_show_all_locks();
++}
++
++void __cpuinit init_idle_bootup_task(struct task_struct *idle)
++{
++ idle->sched_class = &idle_sched_class;
++}
++
++/**
++ * init_idle - set up an idle thread for a given CPU
++ * @idle: task in question
++ * @cpu: cpu the idle task belongs to
++ *
++ * NOTE: this function does not set the idle thread's NEED_RESCHED
++ * flag, to make booting more robust.
++ */
++void __cpuinit init_idle(struct task_struct *idle, int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long flags;
++
++ __sched_fork(idle);
++ idle->se.exec_start = sched_clock();
++
++ idle->prio = idle->normal_prio = MAX_PRIO;
++ idle->cpus_allowed = cpumask_of_cpu(cpu);
++ __set_task_cpu(idle, cpu);
++
++ spin_lock_irqsave(&rq->lock, flags);
++ rq->curr = rq->idle = idle;
++#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
++ idle->oncpu = 1;
++#endif
++ spin_unlock_irqrestore(&rq->lock, flags);
++
++ /* Set the preempt count _outside_ the spinlocks! */
++#if defined(CONFIG_PREEMPT)
++ task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
++#else
++ task_thread_info(idle)->preempt_count = 0;
++#endif
++ /*
++ * The idle tasks have their own, simple scheduling class:
++ */
++ idle->sched_class = &idle_sched_class;
++}
++
++/*
++ * In a system that switches off the HZ timer nohz_cpu_mask
++ * indicates which cpus entered this state. This is used
++ * in the rcu update to wait only for active cpus. For system
++ * which do not switch off the HZ timer nohz_cpu_mask should
++ * always be CPU_MASK_NONE.
++ */
++cpumask_t nohz_cpu_mask = CPU_MASK_NONE;
++
++/*
++ * Increase the granularity value when there are more CPUs,
++ * because with more CPUs the 'effective latency' as visible
++ * to users decreases. But the relationship is not linear,
++ * so pick a second-best guess by going with the log2 of the
++ * number of CPUs.
++ *
++ * This idea comes from the SD scheduler of Con Kolivas:
++ */
++static inline void sched_init_granularity(void)
++{
++ unsigned int factor = 1 + ilog2(num_online_cpus());
++ const unsigned long limit = 200000000;
++
++ sysctl_sched_min_granularity *= factor;
++ if (sysctl_sched_min_granularity > limit)
++ sysctl_sched_min_granularity = limit;
++
++ sysctl_sched_latency *= factor;
++ if (sysctl_sched_latency > limit)
++ sysctl_sched_latency = limit;
++
++ sysctl_sched_wakeup_granularity *= factor;
++
++ sysctl_sched_shares_ratelimit *= factor;
++}
++
++#ifdef CONFIG_SMP
++/*
++ * This is how migration works:
++ *
++ * 1) we queue a struct migration_req structure in the source CPU's
++ * runqueue and wake up that CPU's migration thread.
++ * 2) we down() the locked semaphore => thread blocks.
++ * 3) migration thread wakes up (implicitly it forces the migrated
++ * thread off the CPU)
++ * 4) it gets the migration request and checks whether the migrated
++ * task is still in the wrong runqueue.
++ * 5) if it's in the wrong runqueue then the migration thread removes
++ * it and puts it into the right queue.
++ * 6) migration thread up()s the semaphore.
++ * 7) we wake up and the migration is done.
++ */
++
++/*
++ * Change a given task's CPU affinity. Migrate the thread to a
++ * proper CPU and schedule it away if the CPU it's executing on
++ * is removed from the allowed bitmask.
++ *
++ * NOTE: the caller must have a valid reference to the task, the
++ * task must not exit() & deallocate itself prematurely. The
++ * call is not atomic; no spinlocks may be held.
++ */
++int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
++{
++ struct migration_req req;
++ unsigned long flags;
++ struct rq *rq;
++ int ret = 0;
++
++ rq = task_rq_lock(p, &flags);
++ if (!cpus_intersects(*new_mask, cpu_online_map)) {
++ ret = -EINVAL;
++ goto out;
++ }
++
++ if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
++ !cpus_equal(p->cpus_allowed, *new_mask))) {
++ ret = -EINVAL;
++ goto out;
++ }
++
++ if (p->sched_class->set_cpus_allowed)
++ p->sched_class->set_cpus_allowed(p, new_mask);
++ else {
++ p->cpus_allowed = *new_mask;
++ p->rt.nr_cpus_allowed = cpus_weight(*new_mask);
++ }
++
++ /* Can the task run on the task's current CPU? If so, we're done */
++ if (cpu_isset(task_cpu(p), *new_mask))
++ goto out;
++
++ if (migrate_task(p, any_online_cpu(*new_mask), &req)) {
++ /* Need help from migration thread: drop lock and wait. */
++ task_rq_unlock(rq, &flags);
++ wake_up_process(rq->migration_thread);
++ wait_for_completion(&req.done);
++ tlb_migrate_finish(p->mm);
++ return 0;
++ }
++out:
++ task_rq_unlock(rq, &flags);
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
++
++/*
++ * Move (not current) task off this cpu, onto dest cpu. We're doing
++ * this because either it can't run here any more (set_cpus_allowed()
++ * away from this CPU, or CPU going down), or because we're
++ * attempting to rebalance this task on exec (sched_exec).
++ *
++ * So we race with normal scheduler movements, but that's OK, as long
++ * as the task is no longer on this CPU.
++ *
++ * Returns non-zero if task was successfully migrated.
++ */
++static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
++{
++ struct rq *rq_dest, *rq_src;
++ int ret = 0, on_rq;
++
++ if (unlikely(!cpu_active(dest_cpu)))
++ return ret;
++
++ rq_src = cpu_rq(src_cpu);
++ rq_dest = cpu_rq(dest_cpu);
++
++ double_rq_lock(rq_src, rq_dest);
++ /* Already moved. */
++ if (task_cpu(p) != src_cpu)
++ goto done;
++ /* Affinity changed (again). */
++ if (!cpu_isset(dest_cpu, p->cpus_allowed))
++ goto fail;
++
++ on_rq = p->se.on_rq;
++ if (on_rq)
++ deactivate_task(rq_src, p, 0);
++
++ set_task_cpu(p, dest_cpu);
++ if (on_rq) {
++ activate_task(rq_dest, p, 0);
++ check_preempt_curr(rq_dest, p);
++ }
++done:
++ ret = 1;
++fail:
++ double_rq_unlock(rq_src, rq_dest);
++ return ret;
++}
++
++/*
++ * migration_thread - this is a highprio system thread that performs
++ * thread migration by bumping thread off CPU then 'pushing' onto
++ * another runqueue.
++ */
++static int migration_thread(void *data)
++{
++ int cpu = (long)data;
++ struct rq *rq;
++
++ rq = cpu_rq(cpu);
++ BUG_ON(rq->migration_thread != current);
++
++ set_current_state(TASK_INTERRUPTIBLE);
++ while (!kthread_should_stop()) {
++ struct migration_req *req;
++ struct list_head *head;
++
++ spin_lock_irq(&rq->lock);
++
++ if (cpu_is_offline(cpu)) {
++ spin_unlock_irq(&rq->lock);
++ goto wait_to_die;
++ }
++
++ if (rq->active_balance) {
++ active_load_balance(rq, cpu);
++ rq->active_balance = 0;
++ }
++
++ head = &rq->migration_queue;
++
++ if (list_empty(head)) {
++ spin_unlock_irq(&rq->lock);
++ schedule();
++ set_current_state(TASK_INTERRUPTIBLE);
++ continue;
++ }
++ req = list_entry(head->next, struct migration_req, list);
++ list_del_init(head->next);
++
++ spin_unlock(&rq->lock);
++ __migrate_task(req->task, cpu, req->dest_cpu);
++ local_irq_enable();
++
++ complete(&req->done);
++ }
++ __set_current_state(TASK_RUNNING);
++ return 0;
++
++wait_to_die:
++ /* Wait for kthread_stop */
++ set_current_state(TASK_INTERRUPTIBLE);
++ while (!kthread_should_stop()) {
++ schedule();
++ set_current_state(TASK_INTERRUPTIBLE);
++ }
++ __set_current_state(TASK_RUNNING);
++ return 0;
++}
++
++#ifdef CONFIG_HOTPLUG_CPU
++
++static int __migrate_task_irq(struct task_struct *p, int src_cpu, int dest_cpu)
++{
++ int ret;
++
++ local_irq_disable();
++ ret = __migrate_task(p, src_cpu, dest_cpu);
++ local_irq_enable();
++ return ret;
++}
++
++/*
++ * Figure out where task on dead CPU should go, use force if necessary.
++ * NOTE: interrupts should be disabled by the caller
++ */
++static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
++{
++ unsigned long flags;
++ cpumask_t mask;
++ struct rq *rq;
++ int dest_cpu;
++
++ do {
++ /* On same node? */
++ mask = node_to_cpumask(cpu_to_node(dead_cpu));
++ cpus_and(mask, mask, p->cpus_allowed);
++ dest_cpu = any_online_cpu(mask);
++
++ /* On any allowed CPU? */
++ if (dest_cpu >= nr_cpu_ids)
++ dest_cpu = any_online_cpu(p->cpus_allowed);
++
++ /* No more Mr. Nice Guy. */
++ if (dest_cpu >= nr_cpu_ids) {
++ cpumask_t cpus_allowed;
++
++ cpuset_cpus_allowed_locked(p, &cpus_allowed);
++ /*
++ * Try to stay on the same cpuset, where the
++ * current cpuset may be a subset of all cpus.
++ * The cpuset_cpus_allowed_locked() variant of
++ * cpuset_cpus_allowed() will not block. It must be
++ * called within calls to cpuset_lock/cpuset_unlock.
++ */
++ rq = task_rq_lock(p, &flags);
++ p->cpus_allowed = cpus_allowed;
++ dest_cpu = any_online_cpu(p->cpus_allowed);
++ task_rq_unlock(rq, &flags);
++
++ /*
++ * Don't tell them about moving exiting tasks or
++ * kernel threads (both mm NULL), since they never
++ * leave kernel.
++ */
++ if (p->mm && printk_ratelimit()) {
++ printk(KERN_INFO "process %d (%s) no "
++ "longer affine to cpu%d\n",
++ task_pid_nr(p), p->comm, dead_cpu);
++ }
++ }
++ } while (!__migrate_task_irq(p, dead_cpu, dest_cpu));
++}
++
++/*
++ * While a dead CPU has no uninterruptible tasks queued at this point,
++ * it might still have a nonzero ->nr_uninterruptible counter, because
++ * for performance reasons the counter is not stricly tracking tasks to
++ * their home CPUs. So we just add the counter to another CPU's counter,
++ * to keep the global sum constant after CPU-down:
++ */
++static void migrate_nr_uninterruptible(struct rq *rq_src)
++{
++ struct rq *rq_dest = cpu_rq(any_online_cpu(*CPU_MASK_ALL_PTR));
++ unsigned long flags;
++
++ local_irq_save(flags);
++ double_rq_lock(rq_src, rq_dest);
++ rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible;
++ rq_src->nr_uninterruptible = 0;
++ double_rq_unlock(rq_src, rq_dest);
++ local_irq_restore(flags);
++}
++
++/* Run through task list and migrate tasks from the dead cpu. */
++static void migrate_live_tasks(int src_cpu)
++{
++ struct task_struct *p, *t;
++
++ read_lock(&tasklist_lock);
++
++ do_each_thread(t, p) {
++ if (p == current)
++ continue;
++
++ if (task_cpu(p) == src_cpu)
++ move_task_off_dead_cpu(src_cpu, p);
++ } while_each_thread(t, p);
++
++ read_unlock(&tasklist_lock);
++}
++
++/*
++ * Schedules idle task to be the next runnable task on current CPU.
++ * It does so by boosting its priority to highest possible.
++ * Used by CPU offline code.
++ */
++void sched_idle_next(void)
++{
++ int this_cpu = smp_processor_id();
++ struct rq *rq = cpu_rq(this_cpu);
++ struct task_struct *p = rq->idle;
++ unsigned long flags;
++
++ /* cpu has to be offline */
++ BUG_ON(cpu_online(this_cpu));
++
++ /*
++ * Strictly not necessary since rest of the CPUs are stopped by now
++ * and interrupts disabled on the current cpu.
++ */
++ spin_lock_irqsave(&rq->lock, flags);
++
++ __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
++
++ update_rq_clock(rq);
++ activate_task(rq, p, 0);
++
++ spin_unlock_irqrestore(&rq->lock, flags);
++}
++
++/*
++ * Ensures that the idle task is using init_mm right before its cpu goes
++ * offline.
++ */
++void idle_task_exit(void)
++{
++ struct mm_struct *mm = current->active_mm;
++
++ BUG_ON(cpu_online(smp_processor_id()));
++
++ if (mm != &init_mm)
++ switch_mm(mm, &init_mm, current);
++ mmdrop(mm);
++}
++
++/* called under rq->lock with disabled interrupts */
++static void migrate_dead(unsigned int dead_cpu, struct task_struct *p)
++{
++ struct rq *rq = cpu_rq(dead_cpu);
++
++ /* Must be exiting, otherwise would be on tasklist. */
++ BUG_ON(!p->exit_state);
++
++ /* Cannot have done final schedule yet: would have vanished. */
++ BUG_ON(p->state == TASK_DEAD);
++
++ get_task_struct(p);
++
++ /*
++ * Drop lock around migration; if someone else moves it,
++ * that's OK. No task can be added to this CPU, so iteration is
++ * fine.
++ */
++ spin_unlock_irq(&rq->lock);
++ move_task_off_dead_cpu(dead_cpu, p);
++ spin_lock_irq(&rq->lock);
++
++ put_task_struct(p);
++}
++
++/* release_task() removes task from tasklist, so we won't find dead tasks. */
++static void migrate_dead_tasks(unsigned int dead_cpu)
++{
++ struct rq *rq = cpu_rq(dead_cpu);
++ struct task_struct *next;
++
++ for ( ; ; ) {
++ if (!rq->nr_running)
++ break;
++ update_rq_clock(rq);
++ next = pick_next_task(rq, rq->curr);
++ if (!next)
++ break;
++ next->sched_class->put_prev_task(rq, next);
++ migrate_dead(dead_cpu, next);
++
++ }
++}
++#endif /* CONFIG_HOTPLUG_CPU */
++
++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
++
++static struct ctl_table sd_ctl_dir[] = {
++ {
++ .procname = "sched_domain",
++ .mode = 0555,
++ },
++ {0, },
++};
++
++static struct ctl_table sd_ctl_root[] = {
++ {
++ .ctl_name = CTL_KERN,
++ .procname = "kernel",
++ .mode = 0555,
++ .child = sd_ctl_dir,
++ },
++ {0, },
++};
++
++static struct ctl_table *sd_alloc_ctl_entry(int n)
++{
++ struct ctl_table *entry =
++ kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL);
++
++ return entry;
++}
++
++static void sd_free_ctl_entry(struct ctl_table **tablep)
++{
++ struct ctl_table *entry;
++
++ /*
++ * In the intermediate directories, both the child directory and
++ * procname are dynamically allocated and could fail but the mode
++ * will always be set. In the lowest directory the names are
++ * static strings and all have proc handlers.
++ */
++ for (entry = *tablep; entry->mode; entry++) {
++ if (entry->child)
++ sd_free_ctl_entry(&entry->child);
++ if (entry->proc_handler == NULL)
++ kfree(entry->procname);
++ }
++
++ kfree(*tablep);
++ *tablep = NULL;
++}
++
++static void
++set_table_entry(struct ctl_table *entry,
++ const char *procname, void *data, int maxlen,
++ mode_t mode, proc_handler *proc_handler)
++{
++ entry->procname = procname;
++ entry->data = data;
++ entry->maxlen = maxlen;
++ entry->mode = mode;
++ entry->proc_handler = proc_handler;
++}
++
++static struct ctl_table *
++sd_alloc_ctl_domain_table(struct sched_domain *sd)
++{
++ struct ctl_table *table = sd_alloc_ctl_entry(12);
++
++ if (table == NULL)
++ return NULL;
++
++ set_table_entry(&table[0], "min_interval", &sd->min_interval,
++ sizeof(long), 0644, proc_doulongvec_minmax);
++ set_table_entry(&table[1], "max_interval", &sd->max_interval,
++ sizeof(long), 0644, proc_doulongvec_minmax);
++ set_table_entry(&table[2], "busy_idx", &sd->busy_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[3], "idle_idx", &sd->idle_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[5], "wake_idx", &sd->wake_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[7], "busy_factor", &sd->busy_factor,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[9], "cache_nice_tries",
++ &sd->cache_nice_tries,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[10], "flags", &sd->flags,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ /* &table[11] is terminator */
++
++ return table;
++}
++
++static ctl_table *sd_alloc_ctl_cpu_table(int cpu)
++{
++ struct ctl_table *entry, *table;
++ struct sched_domain *sd;
++ int domain_num = 0, i;
++ char buf[32];
++
++ for_each_domain(cpu, sd)
++ domain_num++;
++ entry = table = sd_alloc_ctl_entry(domain_num + 1);
++ if (table == NULL)
++ return NULL;
++
++ i = 0;
++ for_each_domain(cpu, sd) {
++ snprintf(buf, 32, "domain%d", i);
++ entry->procname = kstrdup(buf, GFP_KERNEL);
++ entry->mode = 0555;
++ entry->child = sd_alloc_ctl_domain_table(sd);
++ entry++;
++ i++;
++ }
++ return table;
++}
++
++static struct ctl_table_header *sd_sysctl_header;
++static void register_sched_domain_sysctl(void)
++{
++ int i, cpu_num = num_online_cpus();
++ struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
++ char buf[32];
++
++ WARN_ON(sd_ctl_dir[0].child);
++ sd_ctl_dir[0].child = entry;
++
++ if (entry == NULL)
++ return;
++
++ for_each_online_cpu(i) {
++ snprintf(buf, 32, "cpu%d", i);
++ entry->procname = kstrdup(buf, GFP_KERNEL);
++ entry->mode = 0555;
++ entry->child = sd_alloc_ctl_cpu_table(i);
++ entry++;
++ }
++
++ WARN_ON(sd_sysctl_header);
++ sd_sysctl_header = register_sysctl_table(sd_ctl_root);
++}
++
++/* may be called multiple times per register */
++static void unregister_sched_domain_sysctl(void)
++{
++ if (sd_sysctl_header)
++ unregister_sysctl_table(sd_sysctl_header);
++ sd_sysctl_header = NULL;
++ if (sd_ctl_dir[0].child)
++ sd_free_ctl_entry(&sd_ctl_dir[0].child);
++}
++#else
++static void register_sched_domain_sysctl(void)
++{
++}
++static void unregister_sched_domain_sysctl(void)
++{
++}
++#endif
++
++static void set_rq_online(struct rq *rq)
++{
++ if (!rq->online) {
++ const struct sched_class *class;
++
++ cpu_set(rq->cpu, rq->rd->online);
++ rq->online = 1;
++
++ for_each_class(class) {
++ if (class->rq_online)
++ class->rq_online(rq);
++ }
++ }
++}
++
++static void set_rq_offline(struct rq *rq)
++{
++ if (rq->online) {
++ const struct sched_class *class;
++
++ for_each_class(class) {
++ if (class->rq_offline)
++ class->rq_offline(rq);
++ }
++
++ cpu_clear(rq->cpu, rq->rd->online);
++ rq->online = 0;
++ }
++}
++
++/*
++ * migration_call - callback that gets triggered when a CPU is added.
++ * Here we can start up the necessary migration thread for the new CPU.
++ */
++static int __cpuinit
++migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
++{
++ struct task_struct *p;
++ int cpu = (long)hcpu;
++ unsigned long flags;
++ struct rq *rq;
++
++ switch (action) {
++
++ case CPU_UP_PREPARE:
++ case CPU_UP_PREPARE_FROZEN:
++ p = kthread_create(migration_thread, hcpu, "migration/%d", cpu);
++ if (IS_ERR(p))
++ return NOTIFY_BAD;
++ kthread_bind(p, cpu);
++ /* Must be high prio: stop_machine expects to yield to it. */
++ rq = task_rq_lock(p, &flags);
++ __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
++ task_rq_unlock(rq, &flags);
++ cpu_rq(cpu)->migration_thread = p;
++ break;
++
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ /* Strictly unnecessary, as first user will wake it. */
++ wake_up_process(cpu_rq(cpu)->migration_thread);
++
++ /* Update our root-domain */
++ rq = cpu_rq(cpu);
++ spin_lock_irqsave(&rq->lock, flags);
++ if (rq->rd) {
++ BUG_ON(!cpu_isset(cpu, rq->rd->span));
++
++ set_rq_online(rq);
++ }
++ spin_unlock_irqrestore(&rq->lock, flags);
++ break;
++
++#ifdef CONFIG_HOTPLUG_CPU
++ case CPU_UP_CANCELED:
++ case CPU_UP_CANCELED_FROZEN:
++ if (!cpu_rq(cpu)->migration_thread)
++ break;
++ /* Unbind it from offline cpu so it can run. Fall thru. */
++ kthread_bind(cpu_rq(cpu)->migration_thread,
++ any_online_cpu(cpu_online_map));
++ kthread_stop(cpu_rq(cpu)->migration_thread);
++ cpu_rq(cpu)->migration_thread = NULL;
++ break;
++
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ cpuset_lock(); /* around calls to cpuset_cpus_allowed_lock() */
++ migrate_live_tasks(cpu);
++ rq = cpu_rq(cpu);
++ kthread_stop(rq->migration_thread);
++ rq->migration_thread = NULL;
++ /* Idle task back to normal (off runqueue, low prio) */
++ spin_lock_irq(&rq->lock);
++ update_rq_clock(rq);
++ deactivate_task(rq, rq->idle, 0);
++ rq->idle->static_prio = MAX_PRIO;
++ __setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
++ rq->idle->sched_class = &idle_sched_class;
++ migrate_dead_tasks(cpu);
++ spin_unlock_irq(&rq->lock);
++ cpuset_unlock();
++ migrate_nr_uninterruptible(rq);
++ BUG_ON(rq->nr_running != 0);
++
++ /*
++ * No need to migrate the tasks: it was best-effort if
++ * they didn't take sched_hotcpu_mutex. Just wake up
++ * the requestors.
++ */
++ spin_lock_irq(&rq->lock);
++ while (!list_empty(&rq->migration_queue)) {
++ struct migration_req *req;
++
++ req = list_entry(rq->migration_queue.next,
++ struct migration_req, list);
++ list_del_init(&req->list);
++ spin_unlock_irq(&rq->lock);
++ complete(&req->done);
++ spin_lock_irq(&rq->lock);
++ }
++ spin_unlock_irq(&rq->lock);
++ break;
++
++ case CPU_DYING:
++ case CPU_DYING_FROZEN:
++ /* Update our root-domain */
++ rq = cpu_rq(cpu);
++ spin_lock_irqsave(&rq->lock, flags);
++ if (rq->rd) {
++ BUG_ON(!cpu_isset(cpu, rq->rd->span));
++ set_rq_offline(rq);
++ }
++ spin_unlock_irqrestore(&rq->lock, flags);
++ break;
++#endif
++ }
++ return NOTIFY_OK;
++}
++
++/* Register at highest priority so that task migration (migrate_all_tasks)
++ * happens before everything else.
++ */
++static struct notifier_block __cpuinitdata migration_notifier = {
++ .notifier_call = migration_call,
++ .priority = 10
++};
++
++static int __init migration_init(void)
++{
++ void *cpu = (void *)(long)smp_processor_id();
++ int err;
++
++ /* Start one for the boot CPU: */
++ err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
++ BUG_ON(err == NOTIFY_BAD);
++ migration_call(&migration_notifier, CPU_ONLINE, cpu);
++ register_cpu_notifier(&migration_notifier);
++
++ return err;
++}
++early_initcall(migration_init);
++#endif
++
++#ifdef CONFIG_SMP
++
++#ifdef CONFIG_SCHED_DEBUG
++
++static inline const char *sd_level_to_string(enum sched_domain_level lvl)
++{
++ switch (lvl) {
++ case SD_LV_NONE:
++ return "NONE";
++ case SD_LV_SIBLING:
++ return "SIBLING";
++ case SD_LV_MC:
++ return "MC";
++ case SD_LV_CPU:
++ return "CPU";
++ case SD_LV_NODE:
++ return "NODE";
++ case SD_LV_ALLNODES:
++ return "ALLNODES";
++ case SD_LV_MAX:
++ return "MAX";
++
++ }
++ return "MAX";
++}
++
++static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
++ cpumask_t *groupmask)
++{
++ struct sched_group *group = sd->groups;
++ char str[256];
++
++ cpulist_scnprintf(str, sizeof(str), sd->span);
++ cpus_clear(*groupmask);
++
++ printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
++
++ if (!(sd->flags & SD_LOAD_BALANCE)) {
++ printk("does not load-balance\n");
++ if (sd->parent)
++ printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain"
++ " has parent");
++ return -1;
++ }
++
++ printk(KERN_CONT "span %s level %s\n",
++ str, sd_level_to_string(sd->level));
++
++ if (!cpu_isset(cpu, sd->span)) {
++ printk(KERN_ERR "ERROR: domain->span does not contain "
++ "CPU%d\n", cpu);
++ }
++ if (!cpu_isset(cpu, group->cpumask)) {
++ printk(KERN_ERR "ERROR: domain->groups does not contain"
++ " CPU%d\n", cpu);
++ }
++
++ printk(KERN_DEBUG "%*s groups:", level + 1, "");
++ do {
++ if (!group) {
++ printk("\n");
++ printk(KERN_ERR "ERROR: group is NULL\n");
++ break;
++ }
++
++ if (!group->__cpu_power) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: domain->cpu_power not "
++ "set\n");
++ break;
++ }
++
++ if (!cpus_weight(group->cpumask)) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: empty group\n");
++ break;
++ }
++
++ if (cpus_intersects(*groupmask, group->cpumask)) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: repeated CPUs\n");
++ break;
++ }
++
++ cpus_or(*groupmask, *groupmask, group->cpumask);
++
++ cpulist_scnprintf(str, sizeof(str), group->cpumask);
++ printk(KERN_CONT " %s", str);
++
++ group = group->next;
++ } while (group != sd->groups);
++ printk(KERN_CONT "\n");
++
++ if (!cpus_equal(sd->span, *groupmask))
++ printk(KERN_ERR "ERROR: groups don't span domain->span\n");
++
++ if (sd->parent && !cpus_subset(*groupmask, sd->parent->span))
++ printk(KERN_ERR "ERROR: parent span is not a superset "
++ "of domain->span\n");
++ return 0;
++}
++
++static void sched_domain_debug(struct sched_domain *sd, int cpu)
++{
++ cpumask_t *groupmask;
++ int level = 0;
++
++ if (!sd) {
++ printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
++ return;
++ }
++
++ printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
++
++ groupmask = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
++ if (!groupmask) {
++ printk(KERN_DEBUG "Cannot load-balance (out of memory)\n");
++ return;
++ }
++
++ for (;;) {
++ if (sched_domain_debug_one(sd, cpu, level, groupmask))
++ break;
++ level++;
++ sd = sd->parent;
++ if (!sd)
++ break;
++ }
++ kfree(groupmask);
++}
++#else /* !CONFIG_SCHED_DEBUG */
++# define sched_domain_debug(sd, cpu) do { } while (0)
++#endif /* CONFIG_SCHED_DEBUG */
++
++static int sd_degenerate(struct sched_domain *sd)
++{
++ if (cpus_weight(sd->span) == 1)
++ return 1;
++
++ /* Following flags need at least 2 groups */
++ if (sd->flags & (SD_LOAD_BALANCE |
++ SD_BALANCE_NEWIDLE |
++ SD_BALANCE_FORK |
++ SD_BALANCE_EXEC |
++ SD_SHARE_CPUPOWER |
++ SD_SHARE_PKG_RESOURCES)) {
++ if (sd->groups != sd->groups->next)
++ return 0;
++ }
++
++ /* Following flags don't use groups */
++ if (sd->flags & (SD_WAKE_IDLE |
++ SD_WAKE_AFFINE |
++ SD_WAKE_BALANCE))
++ return 0;
++
++ return 1;
++}
++
++static int
++sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
++{
++ unsigned long cflags = sd->flags, pflags = parent->flags;
++
++ if (sd_degenerate(parent))
++ return 1;
++
++ if (!cpus_equal(sd->span, parent->span))
++ return 0;
++
++ /* Does parent contain flags not in child? */
++ /* WAKE_BALANCE is a subset of WAKE_AFFINE */
++ if (cflags & SD_WAKE_AFFINE)
++ pflags &= ~SD_WAKE_BALANCE;
++ /* Flags needing groups don't count if only 1 group in parent */
++ if (parent->groups == parent->groups->next) {
++ pflags &= ~(SD_LOAD_BALANCE |
++ SD_BALANCE_NEWIDLE |
++ SD_BALANCE_FORK |
++ SD_BALANCE_EXEC |
++ SD_SHARE_CPUPOWER |
++ SD_SHARE_PKG_RESOURCES);
++ }
++ if (~cflags & pflags)
++ return 0;
++
++ return 1;
++}
++
++static void rq_attach_root(struct rq *rq, struct root_domain *rd)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&rq->lock, flags);
++
++ if (rq->rd) {
++ struct root_domain *old_rd = rq->rd;
++
++ if (cpu_isset(rq->cpu, old_rd->online))
++ set_rq_offline(rq);
++
++ cpu_clear(rq->cpu, old_rd->span);
++
++ if (atomic_dec_and_test(&old_rd->refcount))
++ kfree(old_rd);
++ }
++
++ atomic_inc(&rd->refcount);
++ rq->rd = rd;
++
++ cpu_set(rq->cpu, rd->span);
++ if (cpu_isset(rq->cpu, cpu_online_map))
++ set_rq_online(rq);
++
++ spin_unlock_irqrestore(&rq->lock, flags);
++}
++
++static void init_rootdomain(struct root_domain *rd)
++{
++ memset(rd, 0, sizeof(*rd));
++
++ cpus_clear(rd->span);
++ cpus_clear(rd->online);
++
++ cpupri_init(&rd->cpupri);
++}
++
++static void init_defrootdomain(void)
++{
++ init_rootdomain(&def_root_domain);
++ atomic_set(&def_root_domain.refcount, 1);
++}
++
++static struct root_domain *alloc_rootdomain(void)
++{
++ struct root_domain *rd;
++
++ rd = kmalloc(sizeof(*rd), GFP_KERNEL);
++ if (!rd)
++ return NULL;
++
++ init_rootdomain(rd);
++
++ return rd;
++}
++
++/*
++ * Attach the domain 'sd' to 'cpu' as its base domain. Callers must
++ * hold the hotplug lock.
++ */
++static void
++cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ struct sched_domain *tmp;
++
++ /* Remove the sched domains which do not contribute to scheduling. */
++ for (tmp = sd; tmp; ) {
++ struct sched_domain *parent = tmp->parent;
++ if (!parent)
++ break;
++
++ if (sd_parent_degenerate(tmp, parent)) {
++ tmp->parent = parent->parent;
++ if (parent->parent)
++ parent->parent->child = tmp;
++ } else
++ tmp = tmp->parent;
++ }
++
++ if (sd && sd_degenerate(sd)) {
++ sd = sd->parent;
++ if (sd)
++ sd->child = NULL;
++ }
++
++ sched_domain_debug(sd, cpu);
++
++ rq_attach_root(rq, rd);
++ rcu_assign_pointer(rq->sd, sd);
++}
++
++/* cpus with isolated domains */
++static cpumask_t cpu_isolated_map = CPU_MASK_NONE;
++
++/* Setup the mask of cpus configured for isolated domains */
++static int __init isolated_cpu_setup(char *str)
++{
++ static int __initdata ints[NR_CPUS];
++ int i;
++
++ str = get_options(str, ARRAY_SIZE(ints), ints);
++ cpus_clear(cpu_isolated_map);
++ for (i = 1; i <= ints[0]; i++)
++ if (ints[i] < NR_CPUS)
++ cpu_set(ints[i], cpu_isolated_map);
++ return 1;
++}
++
++__setup("isolcpus=", isolated_cpu_setup);
++
++/*
++ * init_sched_build_groups takes the cpumask we wish to span, and a pointer
++ * to a function which identifies what group(along with sched group) a CPU
++ * belongs to. The return value of group_fn must be a >= 0 and < NR_CPUS
++ * (due to the fact that we keep track of groups covered with a cpumask_t).
++ *
++ * init_sched_build_groups will build a circular linked list of the groups
++ * covered by the given span, and will set each group's ->cpumask correctly,
++ * and ->cpu_power to 0.
++ */
++static void
++init_sched_build_groups(const cpumask_t *span, const cpumask_t *cpu_map,
++ int (*group_fn)(int cpu, const cpumask_t *cpu_map,
++ struct sched_group **sg,
++ cpumask_t *tmpmask),
++ cpumask_t *covered, cpumask_t *tmpmask)
++{
++ struct sched_group *first = NULL, *last = NULL;
++ int i;
++
++ cpus_clear(*covered);
++
++ for_each_cpu_mask_nr(i, *span) {
++ struct sched_group *sg;
++ int group = group_fn(i, cpu_map, &sg, tmpmask);
++ int j;
++
++ if (cpu_isset(i, *covered))
++ continue;
++
++ cpus_clear(sg->cpumask);
++ sg->__cpu_power = 0;
++
++ for_each_cpu_mask_nr(j, *span) {
++ if (group_fn(j, cpu_map, NULL, tmpmask) != group)
++ continue;
++
++ cpu_set(j, *covered);
++ cpu_set(j, sg->cpumask);
++ }
++ if (!first)
++ first = sg;
++ if (last)
++ last->next = sg;
++ last = sg;
++ }
++ last->next = first;
++}
++
++#define SD_NODES_PER_DOMAIN 16
++
++#ifdef CONFIG_NUMA
++
++/**
++ * find_next_best_node - find the next node to include in a sched_domain
++ * @node: node whose sched_domain we're building
++ * @used_nodes: nodes already in the sched_domain
++ *
++ * Find the next node to include in a given scheduling domain. Simply
++ * finds the closest node not already in the @used_nodes map.
++ *
++ * Should use nodemask_t.
++ */
++static int find_next_best_node(int node, nodemask_t *used_nodes)
++{
++ int i, n, val, min_val, best_node = 0;
++
++ min_val = INT_MAX;
++
++ for (i = 0; i < nr_node_ids; i++) {
++ /* Start at @node */
++ n = (node + i) % nr_node_ids;
++
++ if (!nr_cpus_node(n))
++ continue;
++
++ /* Skip already used nodes */
++ if (node_isset(n, *used_nodes))
++ continue;
++
++ /* Simple min distance search */
++ val = node_distance(node, n);
++
++ if (val < min_val) {
++ min_val = val;
++ best_node = n;
++ }
++ }
++
++ node_set(best_node, *used_nodes);
++ return best_node;
++}
++
++/**
++ * sched_domain_node_span - get a cpumask for a node's sched_domain
++ * @node: node whose cpumask we're constructing
++ * @span: resulting cpumask
++ *
++ * Given a node, construct a good cpumask for its sched_domain to span. It
++ * should be one that prevents unnecessary balancing, but also spreads tasks
++ * out optimally.
++ */
++static void sched_domain_node_span(int node, cpumask_t *span)
++{
++ nodemask_t used_nodes;
++ node_to_cpumask_ptr(nodemask, node);
++ int i;
++
++ cpus_clear(*span);
++ nodes_clear(used_nodes);
++
++ cpus_or(*span, *span, *nodemask);
++ node_set(node, used_nodes);
++
++ for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
++ int next_node = find_next_best_node(node, &used_nodes);
++
++ node_to_cpumask_ptr_next(nodemask, next_node);
++ cpus_or(*span, *span, *nodemask);
++ }
++}
++#endif /* CONFIG_NUMA */
++
++int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
++
++/*
++ * SMT sched-domains:
++ */
++#ifdef CONFIG_SCHED_SMT
++static DEFINE_PER_CPU(struct sched_domain, cpu_domains);
++static DEFINE_PER_CPU(struct sched_group, sched_group_cpus);
++
++static int
++cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
++ cpumask_t *unused)
++{
++ if (sg)
++ *sg = &per_cpu(sched_group_cpus, cpu);
++ return cpu;
++}
++#endif /* CONFIG_SCHED_SMT */
++
++/*
++ * multi-core sched-domains:
++ */
++#ifdef CONFIG_SCHED_MC
++static DEFINE_PER_CPU(struct sched_domain, core_domains);
++static DEFINE_PER_CPU(struct sched_group, sched_group_core);
++#endif /* CONFIG_SCHED_MC */
++
++#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
++static int
++cpu_to_core_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
++ cpumask_t *mask)
++{
++ int group;
++
++ *mask = per_cpu(cpu_sibling_map, cpu);
++ cpus_and(*mask, *mask, *cpu_map);
++ group = first_cpu(*mask);
++ if (sg)
++ *sg = &per_cpu(sched_group_core, group);
++ return group;
++}
++#elif defined(CONFIG_SCHED_MC)
++static int
++cpu_to_core_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
++ cpumask_t *unused)
++{
++ if (sg)
++ *sg = &per_cpu(sched_group_core, cpu);
++ return cpu;
++}
++#endif
++
++static DEFINE_PER_CPU(struct sched_domain, phys_domains);
++static DEFINE_PER_CPU(struct sched_group, sched_group_phys);
++
++static int
++cpu_to_phys_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
++ cpumask_t *mask)
++{
++ int group;
++#ifdef CONFIG_SCHED_MC
++ *mask = cpu_coregroup_map(cpu);
++ cpus_and(*mask, *mask, *cpu_map);
++ group = first_cpu(*mask);
++#elif defined(CONFIG_SCHED_SMT)
++ *mask = per_cpu(cpu_sibling_map, cpu);
++ cpus_and(*mask, *mask, *cpu_map);
++ group = first_cpu(*mask);
++#else
++ group = cpu;
++#endif
++ if (sg)
++ *sg = &per_cpu(sched_group_phys, group);
++ return group;
++}
++
++#ifdef CONFIG_NUMA
++/*
++ * The init_sched_build_groups can't handle what we want to do with node
++ * groups, so roll our own. Now each node has its own list of groups which
++ * gets dynamically allocated.
++ */
++static DEFINE_PER_CPU(struct sched_domain, node_domains);
++static struct sched_group ***sched_group_nodes_bycpu;
++
++static DEFINE_PER_CPU(struct sched_domain, allnodes_domains);
++static DEFINE_PER_CPU(struct sched_group, sched_group_allnodes);
++
++static int cpu_to_allnodes_group(int cpu, const cpumask_t *cpu_map,
++ struct sched_group **sg, cpumask_t *nodemask)
++{
++ int group;
++
++ *nodemask = node_to_cpumask(cpu_to_node(cpu));
++ cpus_and(*nodemask, *nodemask, *cpu_map);
++ group = first_cpu(*nodemask);
++
++ if (sg)
++ *sg = &per_cpu(sched_group_allnodes, group);
++ return group;
++}
++
++static void init_numa_sched_groups_power(struct sched_group *group_head)
++{
++ struct sched_group *sg = group_head;
++ int j;
++
++ if (!sg)
++ return;
++ do {
++ for_each_cpu_mask_nr(j, sg->cpumask) {
++ struct sched_domain *sd;
++
++ sd = &per_cpu(phys_domains, j);
++ if (j != first_cpu(sd->groups->cpumask)) {
++ /*
++ * Only add "power" once for each
++ * physical package.
++ */
++ continue;
++ }
++
++ sg_inc_cpu_power(sg, sd->groups->__cpu_power);
++ }
++ sg = sg->next;
++ } while (sg != group_head);
++}
++#endif /* CONFIG_NUMA */
++
++#ifdef CONFIG_NUMA
++/* Free memory allocated for various sched_group structures */
++static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
++{
++ int cpu, i;
++
++ for_each_cpu_mask_nr(cpu, *cpu_map) {
++ struct sched_group **sched_group_nodes
++ = sched_group_nodes_bycpu[cpu];
++
++ if (!sched_group_nodes)
++ continue;
++
++ for (i = 0; i < nr_node_ids; i++) {
++ struct sched_group *oldsg, *sg = sched_group_nodes[i];
++
++ *nodemask = node_to_cpumask(i);
++ cpus_and(*nodemask, *nodemask, *cpu_map);
++ if (cpus_empty(*nodemask))
++ continue;
++
++ if (sg == NULL)
++ continue;
++ sg = sg->next;
++next_sg:
++ oldsg = sg;
++ sg = sg->next;
++ kfree(oldsg);
++ if (oldsg != sched_group_nodes[i])
++ goto next_sg;
++ }
++ kfree(sched_group_nodes);
++ sched_group_nodes_bycpu[cpu] = NULL;
++ }
++}
++#else /* !CONFIG_NUMA */
++static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
++{
++}
++#endif /* CONFIG_NUMA */
++
++/*
++ * Initialize sched groups cpu_power.
++ *
++ * cpu_power indicates the capacity of sched group, which is used while
++ * distributing the load between different sched groups in a sched domain.
++ * Typically cpu_power for all the groups in a sched domain will be same unless
++ * there are asymmetries in the topology. If there are asymmetries, group
++ * having more cpu_power will pickup more load compared to the group having
++ * less cpu_power.
++ *
++ * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents
++ * the maximum number of tasks a group can handle in the presence of other idle
++ * or lightly loaded groups in the same sched domain.
++ */
++static void init_sched_groups_power(int cpu, struct sched_domain *sd)
++{
++ struct sched_domain *child;
++ struct sched_group *group;
++
++ WARN_ON(!sd || !sd->groups);
++
++ if (cpu != first_cpu(sd->groups->cpumask))
++ return;
++
++ child = sd->child;
++
++ sd->groups->__cpu_power = 0;
++
++ /*
++ * For perf policy, if the groups in child domain share resources
++ * (for example cores sharing some portions of the cache hierarchy
++ * or SMT), then set this domain groups cpu_power such that each group
++ * can handle only one task, when there are other idle groups in the
++ * same sched domain.
++ */
++ if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) &&
++ (child->flags &
++ (SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) {
++ sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE);
++ return;
++ }
++
++ /*
++ * add cpu_power of each child group to this groups cpu_power
++ */
++ group = child->groups;
++ do {
++ sg_inc_cpu_power(sd->groups, group->__cpu_power);
++ group = group->next;
++ } while (group != child->groups);
++}
++
++/*
++ * Initializers for schedule domains
++ * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
++ */
++
++#define SD_INIT(sd, type) sd_init_##type(sd)
++#define SD_INIT_FUNC(type) \
++static noinline void sd_init_##type(struct sched_domain *sd) \
++{ \
++ memset(sd, 0, sizeof(*sd)); \
++ *sd = SD_##type##_INIT; \
++ sd->level = SD_LV_##type; \
++}
++
++SD_INIT_FUNC(CPU)
++#ifdef CONFIG_NUMA
++ SD_INIT_FUNC(ALLNODES)
++ SD_INIT_FUNC(NODE)
++#endif
++#ifdef CONFIG_SCHED_SMT
++ SD_INIT_FUNC(SIBLING)
++#endif
++#ifdef CONFIG_SCHED_MC
++ SD_INIT_FUNC(MC)
++#endif
++
++/*
++ * To minimize stack usage kmalloc room for cpumasks and share the
++ * space as the usage in build_sched_domains() dictates. Used only
++ * if the amount of space is significant.
++ */
++struct allmasks {
++ cpumask_t tmpmask; /* make this one first */
++ union {
++ cpumask_t nodemask;
++ cpumask_t this_sibling_map;
++ cpumask_t this_core_map;
++ };
++ cpumask_t send_covered;
++
++#ifdef CONFIG_NUMA
++ cpumask_t domainspan;
++ cpumask_t covered;
++ cpumask_t notcovered;
++#endif
++};
++
++#if NR_CPUS > 128
++#define SCHED_CPUMASK_ALLOC 1
++#define SCHED_CPUMASK_FREE(v) kfree(v)
++#define SCHED_CPUMASK_DECLARE(v) struct allmasks *v
++#else
++#define SCHED_CPUMASK_ALLOC 0
++#define SCHED_CPUMASK_FREE(v)
++#define SCHED_CPUMASK_DECLARE(v) struct allmasks _v, *v = &_v
++#endif
++
++#define SCHED_CPUMASK_VAR(v, a) cpumask_t *v = (cpumask_t *) \
++ ((unsigned long)(a) + offsetof(struct allmasks, v))
++
++static int default_relax_domain_level = -1;
++
++static int __init setup_relax_domain_level(char *str)
++{
++ unsigned long val;
++
++ val = simple_strtoul(str, NULL, 0);
++ if (val < SD_LV_MAX)
++ default_relax_domain_level = val;
++
++ return 1;
++}
++__setup("relax_domain_level=", setup_relax_domain_level);
++
++static void set_domain_attribute(struct sched_domain *sd,
++ struct sched_domain_attr *attr)
++{
++ int request;
++
++ if (!attr || attr->relax_domain_level < 0) {
++ if (default_relax_domain_level < 0)
++ return;
++ else
++ request = default_relax_domain_level;
++ } else
++ request = attr->relax_domain_level;
++ if (request < sd->level) {
++ /* turn off idle balance on this domain */
++ sd->flags &= ~(SD_WAKE_IDLE|SD_BALANCE_NEWIDLE);
++ } else {
++ /* turn on idle balance on this domain */
++ sd->flags |= (SD_WAKE_IDLE_FAR|SD_BALANCE_NEWIDLE);
++ }
++}
++
++/*
++ * Build sched domains for a given set of cpus and attach the sched domains
++ * to the individual cpus
++ */
++static int __build_sched_domains(const cpumask_t *cpu_map,
++ struct sched_domain_attr *attr)
++{
++ int i;
++ struct root_domain *rd;
++ SCHED_CPUMASK_DECLARE(allmasks);
++ cpumask_t *tmpmask;
++#ifdef CONFIG_NUMA
++ struct sched_group **sched_group_nodes = NULL;
++ int sd_allnodes = 0;
++
++ /*
++ * Allocate the per-node list of sched groups
++ */
++ sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *),
++ GFP_KERNEL);
++ if (!sched_group_nodes) {
++ printk(KERN_WARNING "Can not alloc sched group node list\n");
++ return -ENOMEM;
++ }
++#endif
++
++ rd = alloc_rootdomain();
++ if (!rd) {
++ printk(KERN_WARNING "Cannot alloc root domain\n");
++#ifdef CONFIG_NUMA
++ kfree(sched_group_nodes);
++#endif
++ return -ENOMEM;
++ }
++
++#if SCHED_CPUMASK_ALLOC
++ /* get space for all scratch cpumask variables */
++ allmasks = kmalloc(sizeof(*allmasks), GFP_KERNEL);
++ if (!allmasks) {
++ printk(KERN_WARNING "Cannot alloc cpumask array\n");
++ kfree(rd);
++#ifdef CONFIG_NUMA
++ kfree(sched_group_nodes);
++#endif
++ return -ENOMEM;
++ }
++#endif
++ tmpmask = (cpumask_t *)allmasks;
++
++
++#ifdef CONFIG_NUMA
++ sched_group_nodes_bycpu[first_cpu(*cpu_map)] = sched_group_nodes;
++#endif
++
++ /*
++ * Set up domains for cpus specified by the cpu_map.
++ */
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ struct sched_domain *sd = NULL, *p;
++ SCHED_CPUMASK_VAR(nodemask, allmasks);
++
++ *nodemask = node_to_cpumask(cpu_to_node(i));
++ cpus_and(*nodemask, *nodemask, *cpu_map);
++
++#ifdef CONFIG_NUMA
++ if (cpus_weight(*cpu_map) >
++ SD_NODES_PER_DOMAIN*cpus_weight(*nodemask)) {
++ sd = &per_cpu(allnodes_domains, i);
++ SD_INIT(sd, ALLNODES);
++ set_domain_attribute(sd, attr);
++ sd->span = *cpu_map;
++ cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
++ p = sd;
++ sd_allnodes = 1;
++ } else
++ p = NULL;
++
++ sd = &per_cpu(node_domains, i);
++ SD_INIT(sd, NODE);
++ set_domain_attribute(sd, attr);
++ sched_domain_node_span(cpu_to_node(i), &sd->span);
++ sd->parent = p;
++ if (p)
++ p->child = sd;
++ cpus_and(sd->span, sd->span, *cpu_map);
++#endif
++
++ p = sd;
++ sd = &per_cpu(phys_domains, i);
++ SD_INIT(sd, CPU);
++ set_domain_attribute(sd, attr);
++ sd->span = *nodemask;
++ sd->parent = p;
++ if (p)
++ p->child = sd;
++ cpu_to_phys_group(i, cpu_map, &sd->groups, tmpmask);
++
++#ifdef CONFIG_SCHED_MC
++ p = sd;
++ sd = &per_cpu(core_domains, i);
++ SD_INIT(sd, MC);
++ set_domain_attribute(sd, attr);
++ sd->span = cpu_coregroup_map(i);
++ cpus_and(sd->span, sd->span, *cpu_map);
++ sd->parent = p;
++ p->child = sd;
++ cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
++#endif
++
++#ifdef CONFIG_SCHED_SMT
++ p = sd;
++ sd = &per_cpu(cpu_domains, i);
++ SD_INIT(sd, SIBLING);
++ set_domain_attribute(sd, attr);
++ sd->span = per_cpu(cpu_sibling_map, i);
++ cpus_and(sd->span, sd->span, *cpu_map);
++ sd->parent = p;
++ p->child = sd;
++ cpu_to_cpu_group(i, cpu_map, &sd->groups, tmpmask);
++#endif
++ }
++
++#ifdef CONFIG_SCHED_SMT
++ /* Set up CPU (sibling) groups */
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ SCHED_CPUMASK_VAR(this_sibling_map, allmasks);
++ SCHED_CPUMASK_VAR(send_covered, allmasks);
++
++ *this_sibling_map = per_cpu(cpu_sibling_map, i);
++ cpus_and(*this_sibling_map, *this_sibling_map, *cpu_map);
++ if (i != first_cpu(*this_sibling_map))
++ continue;
++
++ init_sched_build_groups(this_sibling_map, cpu_map,
++ &cpu_to_cpu_group,
++ send_covered, tmpmask);
++ }
++#endif
++
++#ifdef CONFIG_SCHED_MC
++ /* Set up multi-core groups */
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ SCHED_CPUMASK_VAR(this_core_map, allmasks);
++ SCHED_CPUMASK_VAR(send_covered, allmasks);
++
++ *this_core_map = cpu_coregroup_map(i);
++ cpus_and(*this_core_map, *this_core_map, *cpu_map);
++ if (i != first_cpu(*this_core_map))
++ continue;
++
++ init_sched_build_groups(this_core_map, cpu_map,
++ &cpu_to_core_group,
++ send_covered, tmpmask);
++ }
++#endif
++
++ /* Set up physical groups */
++ for (i = 0; i < nr_node_ids; i++) {
++ SCHED_CPUMASK_VAR(nodemask, allmasks);
++ SCHED_CPUMASK_VAR(send_covered, allmasks);
++
++ *nodemask = node_to_cpumask(i);
++ cpus_and(*nodemask, *nodemask, *cpu_map);
++ if (cpus_empty(*nodemask))
++ continue;
++
++ init_sched_build_groups(nodemask, cpu_map,
++ &cpu_to_phys_group,
++ send_covered, tmpmask);
++ }
++
++#ifdef CONFIG_NUMA
++ /* Set up node groups */
++ if (sd_allnodes) {
++ SCHED_CPUMASK_VAR(send_covered, allmasks);
++
++ init_sched_build_groups(cpu_map, cpu_map,
++ &cpu_to_allnodes_group,
++ send_covered, tmpmask);
++ }
++
++ for (i = 0; i < nr_node_ids; i++) {
++ /* Set up node groups */
++ struct sched_group *sg, *prev;
++ SCHED_CPUMASK_VAR(nodemask, allmasks);
++ SCHED_CPUMASK_VAR(domainspan, allmasks);
++ SCHED_CPUMASK_VAR(covered, allmasks);
++ int j;
++
++ *nodemask = node_to_cpumask(i);
++ cpus_clear(*covered);
++
++ cpus_and(*nodemask, *nodemask, *cpu_map);
++ if (cpus_empty(*nodemask)) {
++ sched_group_nodes[i] = NULL;
++ continue;
++ }
++
++ sched_domain_node_span(i, domainspan);
++ cpus_and(*domainspan, *domainspan, *cpu_map);
++
++ sg = kmalloc_node(sizeof(struct sched_group), GFP_KERNEL, i);
++ if (!sg) {
++ printk(KERN_WARNING "Can not alloc domain group for "
++ "node %d\n", i);
++ goto error;
++ }
++ sched_group_nodes[i] = sg;
++ for_each_cpu_mask_nr(j, *nodemask) {
++ struct sched_domain *sd;
++
++ sd = &per_cpu(node_domains, j);
++ sd->groups = sg;
++ }
++ sg->__cpu_power = 0;
++ sg->cpumask = *nodemask;
++ sg->next = sg;
++ cpus_or(*covered, *covered, *nodemask);
++ prev = sg;
++
++ for (j = 0; j < nr_node_ids; j++) {
++ SCHED_CPUMASK_VAR(notcovered, allmasks);
++ int n = (i + j) % nr_node_ids;
++ node_to_cpumask_ptr(pnodemask, n);
++
++ cpus_complement(*notcovered, *covered);
++ cpus_and(*tmpmask, *notcovered, *cpu_map);
++ cpus_and(*tmpmask, *tmpmask, *domainspan);
++ if (cpus_empty(*tmpmask))
++ break;
++
++ cpus_and(*tmpmask, *tmpmask, *pnodemask);
++ if (cpus_empty(*tmpmask))
++ continue;
++
++ sg = kmalloc_node(sizeof(struct sched_group),
++ GFP_KERNEL, i);
++ if (!sg) {
++ printk(KERN_WARNING
++ "Can not alloc domain group for node %d\n", j);
++ goto error;
++ }
++ sg->__cpu_power = 0;
++ sg->cpumask = *tmpmask;
++ sg->next = prev->next;
++ cpus_or(*covered, *covered, *tmpmask);
++ prev->next = sg;
++ prev = sg;
++ }
++ }
++#endif
++
++ /* Calculate CPU power for physical packages and nodes */
++#ifdef CONFIG_SCHED_SMT
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ struct sched_domain *sd = &per_cpu(cpu_domains, i);
++
++ init_sched_groups_power(i, sd);
++ }
++#endif
++#ifdef CONFIG_SCHED_MC
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ struct sched_domain *sd = &per_cpu(core_domains, i);
++
++ init_sched_groups_power(i, sd);
++ }
++#endif
++
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ struct sched_domain *sd = &per_cpu(phys_domains, i);
++
++ init_sched_groups_power(i, sd);
++ }
++
++#ifdef CONFIG_NUMA
++ for (i = 0; i < nr_node_ids; i++)
++ init_numa_sched_groups_power(sched_group_nodes[i]);
++
++ if (sd_allnodes) {
++ struct sched_group *sg;
++
++ cpu_to_allnodes_group(first_cpu(*cpu_map), cpu_map, &sg,
++ tmpmask);
++ init_numa_sched_groups_power(sg);
++ }
++#endif
++
++ /* Attach the domains */
++ for_each_cpu_mask_nr(i, *cpu_map) {
++ struct sched_domain *sd;
++#ifdef CONFIG_SCHED_SMT
++ sd = &per_cpu(cpu_domains, i);
++#elif defined(CONFIG_SCHED_MC)
++ sd = &per_cpu(core_domains, i);
++#else
++ sd = &per_cpu(phys_domains, i);
++#endif
++ cpu_attach_domain(sd, rd, i);
++ }
++
++ SCHED_CPUMASK_FREE((void *)allmasks);
++ return 0;
++
++#ifdef CONFIG_NUMA
++error:
++ free_sched_groups(cpu_map, tmpmask);
++ SCHED_CPUMASK_FREE((void *)allmasks);
++ return -ENOMEM;
++#endif
++}
++
++static int build_sched_domains(const cpumask_t *cpu_map)
++{
++ return __build_sched_domains(cpu_map, NULL);
++}
++
++static cpumask_t *doms_cur; /* current sched domains */
++static int ndoms_cur; /* number of sched domains in 'doms_cur' */
++static struct sched_domain_attr *dattr_cur;
++ /* attribues of custom domains in 'doms_cur' */
++
++/*
++ * Special case: If a kmalloc of a doms_cur partition (array of
++ * cpumask_t) fails, then fallback to a single sched domain,
++ * as determined by the single cpumask_t fallback_doms.
++ */
++static cpumask_t fallback_doms;
++
++void __attribute__((weak)) arch_update_cpu_topology(void)
++{
++}
++
++/*
++ * Set up scheduler domains and groups. Callers must hold the hotplug lock.
++ * For now this just excludes isolated cpus, but could be used to
++ * exclude other special cases in the future.
++ */
++static int arch_init_sched_domains(const cpumask_t *cpu_map)
++{
++ int err;
++
++ arch_update_cpu_topology();
++ ndoms_cur = 1;
++ doms_cur = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
++ if (!doms_cur)
++ doms_cur = &fallback_doms;
++ cpus_andnot(*doms_cur, *cpu_map, cpu_isolated_map);
++ dattr_cur = NULL;
++ err = build_sched_domains(doms_cur);
++ register_sched_domain_sysctl();
++
++ return err;
++}
++
++static void arch_destroy_sched_domains(const cpumask_t *cpu_map,
++ cpumask_t *tmpmask)
++{
++ free_sched_groups(cpu_map, tmpmask);
++}
++
++/*
++ * Detach sched domains from a group of cpus specified in cpu_map
++ * These cpus will now be attached to the NULL domain
++ */
++static void detach_destroy_domains(const cpumask_t *cpu_map)
++{
++ cpumask_t tmpmask;
++ int i;
++
++ unregister_sched_domain_sysctl();
++
++ for_each_cpu_mask_nr(i, *cpu_map)
++ cpu_attach_domain(NULL, &def_root_domain, i);
++ synchronize_sched();
++ arch_destroy_sched_domains(cpu_map, &tmpmask);
++}
++
++/* handle null as "default" */
++static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
++ struct sched_domain_attr *new, int idx_new)
++{
++ struct sched_domain_attr tmp;
++
++ /* fast path */
++ if (!new && !cur)
++ return 1;
++
++ tmp = SD_ATTR_INIT;
++ return !memcmp(cur ? (cur + idx_cur) : &tmp,
++ new ? (new + idx_new) : &tmp,
++ sizeof(struct sched_domain_attr));
++}
++
++/*
++ * Partition sched domains as specified by the 'ndoms_new'
++ * cpumasks in the array doms_new[] of cpumasks. This compares
++ * doms_new[] to the current sched domain partitioning, doms_cur[].
++ * It destroys each deleted domain and builds each new domain.
++ *
++ * 'doms_new' is an array of cpumask_t's of length 'ndoms_new'.
++ * The masks don't intersect (don't overlap.) We should setup one
++ * sched domain for each mask. CPUs not in any of the cpumasks will
++ * not be load balanced. If the same cpumask appears both in the
++ * current 'doms_cur' domains and in the new 'doms_new', we can leave
++ * it as it is.
++ *
++ * The passed in 'doms_new' should be kmalloc'd. This routine takes
++ * ownership of it and will kfree it when done with it. If the caller
++ * failed the kmalloc call, then it can pass in doms_new == NULL &&
++ * ndoms_new == 1, and partition_sched_domains() will fallback to
++ * the single partition 'fallback_doms', it also forces the domains
++ * to be rebuilt.
++ *
++ * If doms_new == NULL it will be replaced with cpu_online_map.
++ * ndoms_new == 0 is a special case for destroying existing domains,
++ * and it will not create the default domain.
++ *
++ * Call with hotplug lock held
++ */
++void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
++ struct sched_domain_attr *dattr_new)
++{
++ int i, j, n;
++
++ mutex_lock(&sched_domains_mutex);
++
++ /* always unregister in case we don't destroy any domains */
++ unregister_sched_domain_sysctl();
++
++ n = doms_new ? ndoms_new : 0;
++
++ /* Destroy deleted domains */
++ for (i = 0; i < ndoms_cur; i++) {
++ for (j = 0; j < n; j++) {
++ if (cpus_equal(doms_cur[i], doms_new[j])
++ && dattrs_equal(dattr_cur, i, dattr_new, j))
++ goto match1;
++ }
++ /* no match - a current sched domain not in new doms_new[] */
++ detach_destroy_domains(doms_cur + i);
++match1:
++ ;
++ }
++
++ if (doms_new == NULL) {
++ ndoms_cur = 0;
++ doms_new = &fallback_doms;
++ cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map);
++ dattr_new = NULL;
++ }
++
++ /* Build new domains */
++ for (i = 0; i < ndoms_new; i++) {
++ for (j = 0; j < ndoms_cur; j++) {
++ if (cpus_equal(doms_new[i], doms_cur[j])
++ && dattrs_equal(dattr_new, i, dattr_cur, j))
++ goto match2;
++ }
++ /* no match - add a new doms_new */
++ __build_sched_domains(doms_new + i,
++ dattr_new ? dattr_new + i : NULL);
++match2:
++ ;
++ }
++
++ /* Remember the new sched domains */
++ if (doms_cur != &fallback_doms)
++ kfree(doms_cur);
++ kfree(dattr_cur); /* kfree(NULL) is safe */
++ doms_cur = doms_new;
++ dattr_cur = dattr_new;
++ ndoms_cur = ndoms_new;
++
++ register_sched_domain_sysctl();
++
++ mutex_unlock(&sched_domains_mutex);
++}
++
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++int arch_reinit_sched_domains(void)
++{
++ get_online_cpus();
++
++ /* Destroy domains first to force the rebuild */
++ partition_sched_domains(0, NULL, NULL);
++
++ rebuild_sched_domains();
++ put_online_cpus();
++
++ return 0;
++}
++
++static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
++{
++ int ret;
++
++ if (buf[0] != '0' && buf[0] != '1')
++ return -EINVAL;
++
++ if (smt)
++ sched_smt_power_savings = (buf[0] == '1');
++ else
++ sched_mc_power_savings = (buf[0] == '1');
++
++ ret = arch_reinit_sched_domains();
++
++ return ret ? ret : count;
++}
++
++#ifdef CONFIG_SCHED_MC
++static ssize_t sched_mc_power_savings_show(struct sysdev_class *class,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_mc_power_savings);
++}
++static ssize_t sched_mc_power_savings_store(struct sysdev_class *class,
++ const char *buf, size_t count)
++{
++ return sched_power_savings_store(buf, count, 0);
++}
++static SYSDEV_CLASS_ATTR(sched_mc_power_savings, 0644,
++ sched_mc_power_savings_show,
++ sched_mc_power_savings_store);
++#endif
++
++#ifdef CONFIG_SCHED_SMT
++static ssize_t sched_smt_power_savings_show(struct sysdev_class *dev,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_smt_power_savings);
++}
++static ssize_t sched_smt_power_savings_store(struct sysdev_class *dev,
++ const char *buf, size_t count)
++{
++ return sched_power_savings_store(buf, count, 1);
++}
++static SYSDEV_CLASS_ATTR(sched_smt_power_savings, 0644,
++ sched_smt_power_savings_show,
++ sched_smt_power_savings_store);
++#endif
++
++int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
++{
++ int err = 0;
++
++#ifdef CONFIG_SCHED_SMT
++ if (smt_capable())
++ err = sysfs_create_file(&cls->kset.kobj,
++ &attr_sched_smt_power_savings.attr);
++#endif
++#ifdef CONFIG_SCHED_MC
++ if (!err && mc_capable())
++ err = sysfs_create_file(&cls->kset.kobj,
++ &attr_sched_mc_power_savings.attr);
++#endif
++ return err;
++}
++#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
++
++#ifndef CONFIG_CPUSETS
++/*
++ * Add online and remove offline CPUs from the scheduler domains.
++ * When cpusets are enabled they take over this function.
++ */
++static int update_sched_domains(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ switch (action) {
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ partition_sched_domains(1, NULL, NULL);
++ return NOTIFY_OK;
++
++ default:
++ return NOTIFY_DONE;
++ }
++}
++#endif
++
++static int update_runtime(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ int cpu = (int)(long)hcpu;
++
++ switch (action) {
++ case CPU_DOWN_PREPARE:
++ case CPU_DOWN_PREPARE_FROZEN:
++ disable_runtime(cpu_rq(cpu));
++ return NOTIFY_OK;
++
++ case CPU_DOWN_FAILED:
++ case CPU_DOWN_FAILED_FROZEN:
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ enable_runtime(cpu_rq(cpu));
++ return NOTIFY_OK;
++
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++void __init sched_init_smp(void)
++{
++ cpumask_t non_isolated_cpus;
++
++#if defined(CONFIG_NUMA)
++ sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
++ GFP_KERNEL);
++ BUG_ON(sched_group_nodes_bycpu == NULL);
++#endif
++ get_online_cpus();
++ mutex_lock(&sched_domains_mutex);
++ arch_init_sched_domains(&cpu_online_map);
++ cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map);
++ if (cpus_empty(non_isolated_cpus))
++ cpu_set(smp_processor_id(), non_isolated_cpus);
++ mutex_unlock(&sched_domains_mutex);
++ put_online_cpus();
++
++#ifndef CONFIG_CPUSETS
++ /* XXX: Theoretical race here - CPU may be hotplugged now */
++ hotcpu_notifier(update_sched_domains, 0);
++#endif
++
++ /* RT runtime code needs to handle some hotplug events */
++ hotcpu_notifier(update_runtime, 0);
++
++ init_hrtick();
++
++ /* Move init over to a non-isolated CPU */
++ if (set_cpus_allowed_ptr(current, &non_isolated_cpus) < 0)
++ BUG();
++ sched_init_granularity();
++}
++#else
++void __init sched_init_smp(void)
++{
++ sched_init_granularity();
++}
++#endif /* CONFIG_SMP */
++
++int in_sched_functions(unsigned long addr)
++{
++ return in_lock_functions(addr) ||
++ (addr >= (unsigned long)__sched_text_start
++ && addr < (unsigned long)__sched_text_end);
++}
++
++static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq)
++{
++ cfs_rq->tasks_timeline = RB_ROOT;
++ INIT_LIST_HEAD(&cfs_rq->tasks);
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ cfs_rq->rq = rq;
++#endif
++ cfs_rq->min_vruntime = (u64)(-(1LL << 20));
++}
++
++static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
++{
++ struct rt_prio_array *array;
++ int i;
++
++ array = &rt_rq->active;
++ for (i = 0; i < MAX_RT_PRIO; i++) {
++ INIT_LIST_HEAD(array->queue + i);
++ __clear_bit(i, array->bitmap);
++ }
++ /* delimiter for bitsearch: */
++ __set_bit(MAX_RT_PRIO, array->bitmap);
++
++#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
++ rt_rq->highest_prio = MAX_RT_PRIO;
++#endif
++#ifdef CONFIG_SMP
++ rt_rq->rt_nr_migratory = 0;
++ rt_rq->overloaded = 0;
++#endif
++
++ rt_rq->rt_time = 0;
++ rt_rq->rt_throttled = 0;
++ rt_rq->rt_runtime = 0;
++ spin_lock_init(&rt_rq->rt_runtime_lock);
++
++#ifdef CONFIG_RT_GROUP_SCHED
++ rt_rq->rt_nr_boosted = 0;
++ rt_rq->rq = rq;
++#endif
++}
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
++ struct sched_entity *se, int cpu, int add,
++ struct sched_entity *parent)
++{
++ struct rq *rq = cpu_rq(cpu);
++ tg->cfs_rq[cpu] = cfs_rq;
++ init_cfs_rq(cfs_rq, rq);
++ cfs_rq->tg = tg;
++ if (add)
++ list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
++
++ tg->se[cpu] = se;
++ /* se could be NULL for init_task_group */
++ if (!se)
++ return;
++
++ if (!parent)
++ se->cfs_rq = &rq->cfs;
++ else
++ se->cfs_rq = parent->my_q;
++
++ se->my_q = cfs_rq;
++ se->load.weight = tg->shares;
++ se->load.inv_weight = 0;
++ se->parent = parent;
++}
++#endif
++
++#ifdef CONFIG_RT_GROUP_SCHED
++static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
++ struct sched_rt_entity *rt_se, int cpu, int add,
++ struct sched_rt_entity *parent)
++{
++ struct rq *rq = cpu_rq(cpu);
++
++ tg->rt_rq[cpu] = rt_rq;
++ init_rt_rq(rt_rq, rq);
++ rt_rq->tg = tg;
++ rt_rq->rt_se = rt_se;
++ rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
++ if (add)
++ list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
++
++ tg->rt_se[cpu] = rt_se;
++ if (!rt_se)
++ return;
++
++ if (!parent)
++ rt_se->rt_rq = &rq->rt;
++ else
++ rt_se->rt_rq = parent->my_q;
++
++ rt_se->my_q = rt_rq;
++ rt_se->parent = parent;
++ INIT_LIST_HEAD(&rt_se->run_list);
++}
++#endif
++
++void __init sched_init(void)
++{
++ int i, j;
++ unsigned long alloc_size = 0, ptr;
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ alloc_size += 2 * nr_cpu_ids * sizeof(void **);
++#endif
++#ifdef CONFIG_RT_GROUP_SCHED
++ alloc_size += 2 * nr_cpu_ids * sizeof(void **);
++#endif
++#ifdef CONFIG_USER_SCHED
++ alloc_size *= 2;
++#endif
++ /*
++ * As sched_init() is called before page_alloc is setup,
++ * we use alloc_bootmem().
++ */
++ if (alloc_size) {
++ ptr = (unsigned long)alloc_bootmem(alloc_size);
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ init_task_group.se = (struct sched_entity **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++ init_task_group.cfs_rq = (struct cfs_rq **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++#ifdef CONFIG_USER_SCHED
++ root_task_group.se = (struct sched_entity **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++ root_task_group.cfs_rq = (struct cfs_rq **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++#endif /* CONFIG_USER_SCHED */
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++#ifdef CONFIG_RT_GROUP_SCHED
++ init_task_group.rt_se = (struct sched_rt_entity **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++ init_task_group.rt_rq = (struct rt_rq **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++#ifdef CONFIG_USER_SCHED
++ root_task_group.rt_se = (struct sched_rt_entity **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++
++ root_task_group.rt_rq = (struct rt_rq **)ptr;
++ ptr += nr_cpu_ids * sizeof(void **);
++#endif /* CONFIG_USER_SCHED */
++#endif /* CONFIG_RT_GROUP_SCHED */
++ }
++
++#ifdef CONFIG_SMP
++ init_defrootdomain();
++#endif
++
++ init_rt_bandwidth(&def_rt_bandwidth,
++ global_rt_period(), global_rt_runtime());
++
++#ifdef CONFIG_RT_GROUP_SCHED
++ init_rt_bandwidth(&init_task_group.rt_bandwidth,
++ global_rt_period(), global_rt_runtime());
++#ifdef CONFIG_USER_SCHED
++ init_rt_bandwidth(&root_task_group.rt_bandwidth,
++ global_rt_period(), RUNTIME_INF);
++#endif /* CONFIG_USER_SCHED */
++#endif /* CONFIG_RT_GROUP_SCHED */
++
++#ifdef CONFIG_GROUP_SCHED
++ list_add(&init_task_group.list, &task_groups);
++ INIT_LIST_HEAD(&init_task_group.children);
++
++#ifdef CONFIG_USER_SCHED
++ INIT_LIST_HEAD(&root_task_group.children);
++ init_task_group.parent = &root_task_group;
++ list_add(&init_task_group.siblings, &root_task_group.children);
++#endif /* CONFIG_USER_SCHED */
++#endif /* CONFIG_GROUP_SCHED */
++
++ for_each_possible_cpu(i) {
++ struct rq *rq;
++
++ rq = cpu_rq(i);
++ spin_lock_init(&rq->lock);
++ rq->nr_running = 0;
++ init_cfs_rq(&rq->cfs, rq);
++ init_rt_rq(&rq->rt, rq);
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ init_task_group.shares = init_task_group_load;
++ INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
++#ifdef CONFIG_CGROUP_SCHED
++ /*
++ * How much cpu bandwidth does init_task_group get?
++ *
++ * In case of task-groups formed thr' the cgroup filesystem, it
++ * gets 100% of the cpu resources in the system. This overall
++ * system cpu resource is divided among the tasks of
++ * init_task_group and its child task-groups in a fair manner,
++ * based on each entity's (task or task-group's) weight
++ * (se->load.weight).
++ *
++ * In other words, if init_task_group has 10 tasks of weight
++ * 1024) and two child groups A0 and A1 (of weight 1024 each),
++ * then A0's share of the cpu resource is:
++ *
++ * A0's bandwidth = 1024 / (10*1024 + 1024 + 1024) = 8.33%
++ *
++ * We achieve this by letting init_task_group's tasks sit
++ * directly in rq->cfs (i.e init_task_group->se[] = NULL).
++ */
++ init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, 1, NULL);
++#elif defined CONFIG_USER_SCHED
++ root_task_group.shares = NICE_0_LOAD;
++ init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, 0, NULL);
++ /*
++ * In case of task-groups formed thr' the user id of tasks,
++ * init_task_group represents tasks belonging to root user.
++ * Hence it forms a sibling of all subsequent groups formed.
++ * In this case, init_task_group gets only a fraction of overall
++ * system cpu resource, based on the weight assigned to root
++ * user's cpu share (INIT_TASK_GROUP_LOAD). This is accomplished
++ * by letting tasks of init_task_group sit in a separate cfs_rq
++ * (init_cfs_rq) and having one entity represent this group of
++ * tasks in rq->cfs (i.e init_task_group->se[] != NULL).
++ */
++ init_tg_cfs_entry(&init_task_group,
++ &per_cpu(init_cfs_rq, i),
++ &per_cpu(init_sched_entity, i), i, 1,
++ root_task_group.se[i]);
++
++#endif
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++
++ rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
++#ifdef CONFIG_RT_GROUP_SCHED
++ INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
++#ifdef CONFIG_CGROUP_SCHED
++ init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, 1, NULL);
++#elif defined CONFIG_USER_SCHED
++ init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, 0, NULL);
++ init_tg_rt_entry(&init_task_group,
++ &per_cpu(init_rt_rq, i),
++ &per_cpu(init_sched_rt_entity, i), i, 1,
++ root_task_group.rt_se[i]);
++#endif
++#endif
++
++ for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
++ rq->cpu_load[j] = 0;
++#ifdef CONFIG_SMP
++ rq->sd = NULL;
++ rq->rd = NULL;
++ rq->active_balance = 0;
++ rq->next_balance = jiffies;
++ rq->push_cpu = 0;
++ rq->cpu = i;
++ rq->online = 0;
++ rq->migration_thread = NULL;
++ INIT_LIST_HEAD(&rq->migration_queue);
++ rq_attach_root(rq, &def_root_domain);
++#endif
++ init_rq_hrtick(rq);
++ atomic_set(&rq->nr_iowait, 0);
++ }
++
++ set_load_weight(&init_task);
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++ INIT_HLIST_HEAD(&init_task.preempt_notifiers);
++#endif
++
++#ifdef CONFIG_SMP
++ open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
++#endif
++
++#ifdef CONFIG_RT_MUTEXES
++ plist_head_init(&init_task.pi_waiters, &init_task.pi_lock);
++#endif
++
++ /*
++ * The boot idle thread does lazy MMU switching as well:
++ */
++ atomic_inc(&init_mm.mm_count);
++ enter_lazy_tlb(&init_mm, current);
++
++ /*
++ * Make us the idle thread. Technically, schedule() should not be
++ * called from this thread, however somewhere below it might be,
++ * but because we are the idle thread, we just pick up running again
++ * when this runqueue becomes "idle".
++ */
++ init_idle(current, smp_processor_id());
++ /*
++ * During early bootup we pretend to be a normal task:
++ */
++ current->sched_class = &fair_sched_class;
++
++ scheduler_running = 1;
++}
++
++#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
++void __might_sleep(char *file, int line)
++{
++#ifdef in_atomic
++ static unsigned long prev_jiffy; /* ratelimiting */
++
++ if ((in_atomic() || irqs_disabled()) &&
++ system_state == SYSTEM_RUNNING && !oops_in_progress) {
++ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
++ return;
++ prev_jiffy = jiffies;
++ printk(KERN_ERR "BUG: sleeping function called from invalid"
++ " context at %s:%d\n", file, line);
++ printk("in_atomic():%d, irqs_disabled():%d\n",
++ in_atomic(), irqs_disabled());
++ debug_show_held_locks(current);
++ if (irqs_disabled())
++ print_irqtrace_events(current);
++ dump_stack();
++ }
++#endif
++}
++EXPORT_SYMBOL(__might_sleep);
++#endif
++
++#ifdef CONFIG_MAGIC_SYSRQ
++static void normalize_task(struct rq *rq, struct task_struct *p)
++{
++ int on_rq;
++
++ update_rq_clock(rq);
++ on_rq = p->se.on_rq;
++ if (on_rq)
++ deactivate_task(rq, p, 0);
++ __setscheduler(rq, p, SCHED_NORMAL, 0);
++ if (on_rq) {
++ activate_task(rq, p, 0);
++ resched_task(rq->curr);
++ }
++}
++
++void normalize_rt_tasks(void)
++{
++ struct task_struct *g, *p;
++ unsigned long flags;
++ struct rq *rq;
++
++ read_lock_irqsave(&tasklist_lock, flags);
++ do_each_thread(g, p) {
++ /*
++ * Only normalize user tasks:
++ */
++ if (!p->mm)
++ continue;
++
++ p->se.exec_start = 0;
++#ifdef CONFIG_SCHEDSTATS
++ p->se.wait_start = 0;
++ p->se.sleep_start = 0;
++ p->se.block_start = 0;
++#endif
++
++ if (!rt_task(p)) {
++ /*
++ * Renice negative nice level userspace
++ * tasks back to 0:
++ */
++ if (TASK_NICE(p) < 0 && p->mm)
++ set_user_nice(p, 0);
++ continue;
++ }
++
++ spin_lock(&p->pi_lock);
++ rq = __task_rq_lock(p);
++
++ normalize_task(rq, p);
++
++ __task_rq_unlock(rq);
++ spin_unlock(&p->pi_lock);
++ } while_each_thread(g, p);
++
++ read_unlock_irqrestore(&tasklist_lock, flags);
++}
++
++#endif /* CONFIG_MAGIC_SYSRQ */
++
++#ifdef CONFIG_IA64
++/*
++ * These functions are only useful for the IA64 MCA handling.
++ *
++ * They can only be called when the whole system has been
++ * stopped - every CPU needs to be quiescent, and no scheduling
++ * activity can take place. Using them for anything else would
++ * be a serious bug, and as a result, they aren't even visible
++ * under any other configuration.
++ */
++
++/**
++ * curr_task - return the current task for a given cpu.
++ * @cpu: the processor in question.
++ *
++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
++ */
++struct task_struct *curr_task(int cpu)
++{
++ return cpu_curr(cpu);
++}
++
++/**
++ * set_curr_task - set the current task for a given cpu.
++ * @cpu: the processor in question.
++ * @p: the task pointer to set.
++ *
++ * Description: This function must only be used when non-maskable interrupts
++ * are serviced on a separate stack. It allows the architecture to switch the
++ * notion of the current task on a cpu in a non-blocking manner. This function
++ * must be called with all CPU's synchronized, and interrupts disabled, the
++ * and caller must save the original value of the current task (see
++ * curr_task() above) and restore that value before reenabling interrupts and
++ * re-starting the system.
++ *
++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
++ */
++void set_curr_task(int cpu, struct task_struct *p)
++{
++ cpu_curr(cpu) = p;
++}
++
++#endif
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++static void free_fair_sched_group(struct task_group *tg)
++{
++ int i;
++
++ for_each_possible_cpu(i) {
++ if (tg->cfs_rq)
++ kfree(tg->cfs_rq[i]);
++ if (tg->se)
++ kfree(tg->se[i]);
++ }
++
++ kfree(tg->cfs_rq);
++ kfree(tg->se);
++}
++
++static
++int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
++{
++ struct cfs_rq *cfs_rq;
++ struct sched_entity *se, *parent_se;
++ struct rq *rq;
++ int i;
++
++ tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL);
++ if (!tg->cfs_rq)
++ goto err;
++ tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL);
++ if (!tg->se)
++ goto err;
++
++ tg->shares = NICE_0_LOAD;
++
++ for_each_possible_cpu(i) {
++ rq = cpu_rq(i);
++
++ cfs_rq = kmalloc_node(sizeof(struct cfs_rq),
++ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
++ if (!cfs_rq)
++ goto err;
++
++ se = kmalloc_node(sizeof(struct sched_entity),
++ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
++ if (!se)
++ goto err;
++
++ parent_se = parent ? parent->se[i] : NULL;
++ init_tg_cfs_entry(tg, cfs_rq, se, i, 0, parent_se);
++ }
++
++ return 1;
++
++ err:
++ return 0;
++}
++
++static inline void register_fair_sched_group(struct task_group *tg, int cpu)
++{
++ list_add_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list,
++ &cpu_rq(cpu)->leaf_cfs_rq_list);
++}
++
++static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
++{
++ list_del_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list);
++}
++#else /* !CONFG_FAIR_GROUP_SCHED */
++static inline void free_fair_sched_group(struct task_group *tg)
++{
++}
++
++static inline
++int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
++{
++ return 1;
++}
++
++static inline void register_fair_sched_group(struct task_group *tg, int cpu)
++{
++}
++
++static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
++{
++}
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++
++#ifdef CONFIG_RT_GROUP_SCHED
++static void free_rt_sched_group(struct task_group *tg)
++{
++ int i;
++
++ destroy_rt_bandwidth(&tg->rt_bandwidth);
++
++ for_each_possible_cpu(i) {
++ if (tg->rt_rq)
++ kfree(tg->rt_rq[i]);
++ if (tg->rt_se)
++ kfree(tg->rt_se[i]);
++ }
++
++ kfree(tg->rt_rq);
++ kfree(tg->rt_se);
++}
++
++static
++int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
++{
++ struct rt_rq *rt_rq;
++ struct sched_rt_entity *rt_se, *parent_se;
++ struct rq *rq;
++ int i;
++
++ tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL);
++ if (!tg->rt_rq)
++ goto err;
++ tg->rt_se = kzalloc(sizeof(rt_se) * nr_cpu_ids, GFP_KERNEL);
++ if (!tg->rt_se)
++ goto err;
++
++ init_rt_bandwidth(&tg->rt_bandwidth,
++ ktime_to_ns(def_rt_bandwidth.rt_period), 0);
++
++ for_each_possible_cpu(i) {
++ rq = cpu_rq(i);
++
++ rt_rq = kmalloc_node(sizeof(struct rt_rq),
++ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
++ if (!rt_rq)
++ goto err;
++
++ rt_se = kmalloc_node(sizeof(struct sched_rt_entity),
++ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
++ if (!rt_se)
++ goto err;
++
++ parent_se = parent ? parent->rt_se[i] : NULL;
++ init_tg_rt_entry(tg, rt_rq, rt_se, i, 0, parent_se);
++ }
++
++ return 1;
++
++ err:
++ return 0;
++}
++
++static inline void register_rt_sched_group(struct task_group *tg, int cpu)
++{
++ list_add_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list,
++ &cpu_rq(cpu)->leaf_rt_rq_list);
++}
++
++static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
++{
++ list_del_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list);
++}
++#else /* !CONFIG_RT_GROUP_SCHED */
++static inline void free_rt_sched_group(struct task_group *tg)
++{
++}
++
++static inline
++int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
++{
++ return 1;
++}
++
++static inline void register_rt_sched_group(struct task_group *tg, int cpu)
++{
++}
++
++static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
++{
++}
++#endif /* CONFIG_RT_GROUP_SCHED */
++
++#ifdef CONFIG_GROUP_SCHED
++static void free_sched_group(struct task_group *tg)
++{
++ free_fair_sched_group(tg);
++ free_rt_sched_group(tg);
++ kfree(tg);
++}
++
++/* allocate runqueue etc for a new task group */
++struct task_group *sched_create_group(struct task_group *parent)
++{
++ struct task_group *tg;
++ unsigned long flags;
++ int i;
++
++ tg = kzalloc(sizeof(*tg), GFP_KERNEL);
++ if (!tg)
++ return ERR_PTR(-ENOMEM);
++
++ if (!alloc_fair_sched_group(tg, parent))
++ goto err;
++
++ if (!alloc_rt_sched_group(tg, parent))
++ goto err;
++
++ spin_lock_irqsave(&task_group_lock, flags);
++ for_each_possible_cpu(i) {
++ register_fair_sched_group(tg, i);
++ register_rt_sched_group(tg, i);
++ }
++ list_add_rcu(&tg->list, &task_groups);
++
++ WARN_ON(!parent); /* root should already exist */
++
++ tg->parent = parent;
++ INIT_LIST_HEAD(&tg->children);
++ list_add_rcu(&tg->siblings, &parent->children);
++ spin_unlock_irqrestore(&task_group_lock, flags);
++
++ return tg;
++
++err:
++ free_sched_group(tg);
++ return ERR_PTR(-ENOMEM);
++}
++
++/* rcu callback to free various structures associated with a task group */
++static void free_sched_group_rcu(struct rcu_head *rhp)
++{
++ /* now it should be safe to free those cfs_rqs */
++ free_sched_group(container_of(rhp, struct task_group, rcu));
++}
++
++/* Destroy runqueue etc associated with a task group */
++void sched_destroy_group(struct task_group *tg)
++{
++ unsigned long flags;
++ int i;
++
++ spin_lock_irqsave(&task_group_lock, flags);
++ for_each_possible_cpu(i) {
++ unregister_fair_sched_group(tg, i);
++ unregister_rt_sched_group(tg, i);
++ }
++ list_del_rcu(&tg->list);
++ list_del_rcu(&tg->siblings);
++ spin_unlock_irqrestore(&task_group_lock, flags);
++
++ /* wait for possible concurrent references to cfs_rqs complete */
++ call_rcu(&tg->rcu, free_sched_group_rcu);
++}
++
++/* change task's runqueue when it moves between groups.
++ * The caller of this function should have put the task in its new group
++ * by now. This function just updates tsk->se.cfs_rq and tsk->se.parent to
++ * reflect its new group.
++ */
++void sched_move_task(struct task_struct *tsk)
++{
++ int on_rq, running;
++ unsigned long flags;
++ struct rq *rq;
++
++ rq = task_rq_lock(tsk, &flags);
++
++ update_rq_clock(rq);
++
++ running = task_current(rq, tsk);
++ on_rq = tsk->se.on_rq;
++
++ if (on_rq)
++ dequeue_task(rq, tsk, 0);
++ if (unlikely(running))
++ tsk->sched_class->put_prev_task(rq, tsk);
++
++ set_task_rq(tsk, task_cpu(tsk));
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ if (tsk->sched_class->moved_group)
++ tsk->sched_class->moved_group(tsk);
++#endif
++
++ if (unlikely(running))
++ tsk->sched_class->set_curr_task(rq);
++ if (on_rq)
++ enqueue_task(rq, tsk, 0);
++
++ task_rq_unlock(rq, &flags);
++}
++#endif /* CONFIG_GROUP_SCHED */
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++static void __set_se_shares(struct sched_entity *se, unsigned long shares)
++{
++ struct cfs_rq *cfs_rq = se->cfs_rq;
++ int on_rq;
++
++ on_rq = se->on_rq;
++ if (on_rq)
++ dequeue_entity(cfs_rq, se, 0);
++
++ se->load.weight = shares;
++ se->load.inv_weight = 0;
++
++ if (on_rq)
++ enqueue_entity(cfs_rq, se, 0);
++}
++
++static void set_se_shares(struct sched_entity *se, unsigned long shares)
++{
++ struct cfs_rq *cfs_rq = se->cfs_rq;
++ struct rq *rq = cfs_rq->rq;
++ unsigned long flags;
++
++ spin_lock_irqsave(&rq->lock, flags);
++ __set_se_shares(se, shares);
++ spin_unlock_irqrestore(&rq->lock, flags);
++}
++
++static DEFINE_MUTEX(shares_mutex);
++
++int sched_group_set_shares(struct task_group *tg, unsigned long shares)
++{
++ int i;
++ unsigned long flags;
++
++ /*
++ * We can't change the weight of the root cgroup.
++ */
++ if (!tg->se[0])
++ return -EINVAL;
++
++ if (shares < MIN_SHARES)
++ shares = MIN_SHARES;
++ else if (shares > MAX_SHARES)
++ shares = MAX_SHARES;
++
++ mutex_lock(&shares_mutex);
++ if (tg->shares == shares)
++ goto done;
++
++ spin_lock_irqsave(&task_group_lock, flags);
++ for_each_possible_cpu(i)
++ unregister_fair_sched_group(tg, i);
++ list_del_rcu(&tg->siblings);
++ spin_unlock_irqrestore(&task_group_lock, flags);
++
++ /* wait for any ongoing reference to this group to finish */
++ synchronize_sched();
++
++ /*
++ * Now we are free to modify the group's share on each cpu
++ * w/o tripping rebalance_share or load_balance_fair.
++ */
++ tg->shares = shares;
++ for_each_possible_cpu(i) {
++ /*
++ * force a rebalance
++ */
++ cfs_rq_set_shares(tg->cfs_rq[i], 0);
++ set_se_shares(tg->se[i], shares);
++ }
++
++ /*
++ * Enable load balance activity on this group, by inserting it back on
++ * each cpu's rq->leaf_cfs_rq_list.
++ */
++ spin_lock_irqsave(&task_group_lock, flags);
++ for_each_possible_cpu(i)
++ register_fair_sched_group(tg, i);
++ list_add_rcu(&tg->siblings, &tg->parent->children);
++ spin_unlock_irqrestore(&task_group_lock, flags);
++done:
++ mutex_unlock(&shares_mutex);
++ return 0;
++}
++
++unsigned long sched_group_shares(struct task_group *tg)
++{
++ return tg->shares;
++}
++#endif
++
++#ifdef CONFIG_RT_GROUP_SCHED
++/*
++ * Ensure that the real time constraints are schedulable.
++ */
++static DEFINE_MUTEX(rt_constraints_mutex);
++
++static unsigned long to_ratio(u64 period, u64 runtime)
++{
++ if (runtime == RUNTIME_INF)
++ return 1ULL << 16;
++
++ return div64_u64(runtime << 16, period);
++}
++
++#ifdef CONFIG_CGROUP_SCHED
++static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
++{
++ struct task_group *tgi, *parent = tg->parent;
++ unsigned long total = 0;
++
++ if (!parent) {
++ if (global_rt_period() < period)
++ return 0;
++
++ return to_ratio(period, runtime) <
++ to_ratio(global_rt_period(), global_rt_runtime());
++ }
++
++ if (ktime_to_ns(parent->rt_bandwidth.rt_period) < period)
++ return 0;
++
++ rcu_read_lock();
++ list_for_each_entry_rcu(tgi, &parent->children, siblings) {
++ if (tgi == tg)
++ continue;
++
++ total += to_ratio(ktime_to_ns(tgi->rt_bandwidth.rt_period),
++ tgi->rt_bandwidth.rt_runtime);
++ }
++ rcu_read_unlock();
++
++ return total + to_ratio(period, runtime) <=
++ to_ratio(ktime_to_ns(parent->rt_bandwidth.rt_period),
++ parent->rt_bandwidth.rt_runtime);
++}
++#elif defined CONFIG_USER_SCHED
++static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
++{
++ struct task_group *tgi;
++ unsigned long total = 0;
++ unsigned long global_ratio =
++ to_ratio(global_rt_period(), global_rt_runtime());
++
++ rcu_read_lock();
++ list_for_each_entry_rcu(tgi, &task_groups, list) {
++ if (tgi == tg)
++ continue;
++
++ total += to_ratio(ktime_to_ns(tgi->rt_bandwidth.rt_period),
++ tgi->rt_bandwidth.rt_runtime);
++ }
++ rcu_read_unlock();
++
++ return total + to_ratio(period, runtime) < global_ratio;
++}
++#endif
++
++/* Must be called with tasklist_lock held */
++static inline int tg_has_rt_tasks(struct task_group *tg)
++{
++ struct task_struct *g, *p;
++ do_each_thread(g, p) {
++ if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg)
++ return 1;
++ } while_each_thread(g, p);
++ return 0;
++}
++
++static int tg_set_bandwidth(struct task_group *tg,
++ u64 rt_period, u64 rt_runtime)
++{
++ int i, err = 0;
++
++ mutex_lock(&rt_constraints_mutex);
++ read_lock(&tasklist_lock);
++ if (rt_runtime == 0 && tg_has_rt_tasks(tg)) {
++ err = -EBUSY;
++ goto unlock;
++ }
++ if (!__rt_schedulable(tg, rt_period, rt_runtime)) {
++ err = -EINVAL;
++ goto unlock;
++ }
++
++ spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock);
++ tg->rt_bandwidth.rt_period = ns_to_ktime(rt_period);
++ tg->rt_bandwidth.rt_runtime = rt_runtime;
++
++ for_each_possible_cpu(i) {
++ struct rt_rq *rt_rq = tg->rt_rq[i];
++
++ spin_lock(&rt_rq->rt_runtime_lock);
++ rt_rq->rt_runtime = rt_runtime;
++ spin_unlock(&rt_rq->rt_runtime_lock);
++ }
++ spin_unlock_irq(&tg->rt_bandwidth.rt_runtime_lock);
++ unlock:
++ read_unlock(&tasklist_lock);
++ mutex_unlock(&rt_constraints_mutex);
++
++ return err;
++}
++
++int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
++{
++ u64 rt_runtime, rt_period;
++
++ rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
++ rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC;
++ if (rt_runtime_us < 0)
++ rt_runtime = RUNTIME_INF;
++
++ return tg_set_bandwidth(tg, rt_period, rt_runtime);
++}
++
++long sched_group_rt_runtime(struct task_group *tg)
++{
++ u64 rt_runtime_us;
++
++ if (tg->rt_bandwidth.rt_runtime == RUNTIME_INF)
++ return -1;
++
++ rt_runtime_us = tg->rt_bandwidth.rt_runtime;
++ do_div(rt_runtime_us, NSEC_PER_USEC);
++ return rt_runtime_us;
++}
++
++int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
++{
++ u64 rt_runtime, rt_period;
++
++ rt_period = (u64)rt_period_us * NSEC_PER_USEC;
++ rt_runtime = tg->rt_bandwidth.rt_runtime;
++
++ if (rt_period == 0)
++ return -EINVAL;
++
++ return tg_set_bandwidth(tg, rt_period, rt_runtime);
++}
++
++long sched_group_rt_period(struct task_group *tg)
++{
++ u64 rt_period_us;
++
++ rt_period_us = ktime_to_ns(tg->rt_bandwidth.rt_period);
++ do_div(rt_period_us, NSEC_PER_USEC);
++ return rt_period_us;
++}
++
++static int sched_rt_global_constraints(void)
++{
++ struct task_group *tg = &root_task_group;
++ u64 rt_runtime, rt_period;
++ int ret = 0;
++
++ if (sysctl_sched_rt_period <= 0)
++ return -EINVAL;
++
++ rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
++ rt_runtime = tg->rt_bandwidth.rt_runtime;
++
++ mutex_lock(&rt_constraints_mutex);
++ if (!__rt_schedulable(tg, rt_period, rt_runtime))
++ ret = -EINVAL;
++ mutex_unlock(&rt_constraints_mutex);
++
++ return ret;
++}
++#else /* !CONFIG_RT_GROUP_SCHED */
++static int sched_rt_global_constraints(void)
++{
++ unsigned long flags;
++ int i;
++
++ if (sysctl_sched_rt_period <= 0)
++ return -EINVAL;
++
++ spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
++ for_each_possible_cpu(i) {
++ struct rt_rq *rt_rq = &cpu_rq(i)->rt;
++
++ spin_lock(&rt_rq->rt_runtime_lock);
++ rt_rq->rt_runtime = global_rt_runtime();
++ spin_unlock(&rt_rq->rt_runtime_lock);
++ }
++ spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
++
++ return 0;
++}
++#endif /* CONFIG_RT_GROUP_SCHED */
++
++int sched_rt_handler(struct ctl_table *table, int write,
++ struct file *filp, void __user *buffer, size_t *lenp,
++ loff_t *ppos)
++{
++ int ret;
++ int old_period, old_runtime;
++ static DEFINE_MUTEX(mutex);
++
++ mutex_lock(&mutex);
++ old_period = sysctl_sched_rt_period;
++ old_runtime = sysctl_sched_rt_runtime;
++
++ ret = proc_dointvec(table, write, filp, buffer, lenp, ppos);
++
++ if (!ret && write) {
++ ret = sched_rt_global_constraints();
++ if (ret) {
++ sysctl_sched_rt_period = old_period;
++ sysctl_sched_rt_runtime = old_runtime;
++ } else {
++ def_rt_bandwidth.rt_runtime = global_rt_runtime();
++ def_rt_bandwidth.rt_period =
++ ns_to_ktime(global_rt_period());
++ }
++ }
++ mutex_unlock(&mutex);
++
++ return ret;
++}
++
++#ifdef CONFIG_CGROUP_SCHED
++
++/* return corresponding task_group object of a cgroup */
++static inline struct task_group *cgroup_tg(struct cgroup *cgrp)
++{
++ return container_of(cgroup_subsys_state(cgrp, cpu_cgroup_subsys_id),
++ struct task_group, css);
++}
++
++static struct cgroup_subsys_state *
++cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
++{
++ struct task_group *tg, *parent;
++
++ if (!cgrp->parent) {
++ /* This is early initialization for the top cgroup */
++ init_task_group.css.cgroup = cgrp;
++ return &init_task_group.css;
++ }
++
++ parent = cgroup_tg(cgrp->parent);
++ tg = sched_create_group(parent);
++ if (IS_ERR(tg))
++ return ERR_PTR(-ENOMEM);
++
++ /* Bind the cgroup to task_group object we just created */
++ tg->css.cgroup = cgrp;
++
++ return &tg->css;
++}
++
++static void
++cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
++{
++ struct task_group *tg = cgroup_tg(cgrp);
++
++ sched_destroy_group(tg);
++}
++
++static int
++cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
++ struct task_struct *tsk)
++{
++#ifdef CONFIG_RT_GROUP_SCHED
++ /* Don't accept realtime tasks when there is no way for them to run */
++ if (rt_task(tsk) && cgroup_tg(cgrp)->rt_bandwidth.rt_runtime == 0)
++ return -EINVAL;
++#else
++ /* We don't support RT-tasks being in separate groups */
++ if (tsk->sched_class != &fair_sched_class)
++ return -EINVAL;
++#endif
++
++ return 0;
++}
++
++static void
++cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
++ struct cgroup *old_cont, struct task_struct *tsk)
++{
++ sched_move_task(tsk);
++}
++
++#ifdef CONFIG_FAIR_GROUP_SCHED
++static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype,
++ u64 shareval)
++{
++ return sched_group_set_shares(cgroup_tg(cgrp), shareval);
++}
++
++static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
++{
++ struct task_group *tg = cgroup_tg(cgrp);
++
++ return (u64) tg->shares;
++}
++#endif /* CONFIG_FAIR_GROUP_SCHED */
++
++#ifdef CONFIG_RT_GROUP_SCHED
++static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
++ s64 val)
++{
++ return sched_group_set_rt_runtime(cgroup_tg(cgrp), val);
++}
++
++static s64 cpu_rt_runtime_read(struct cgroup *cgrp, struct cftype *cft)
++{
++ return sched_group_rt_runtime(cgroup_tg(cgrp));
++}
++
++static int cpu_rt_period_write_uint(struct cgroup *cgrp, struct cftype *cftype,
++ u64 rt_period_us)
++{
++ return sched_group_set_rt_period(cgroup_tg(cgrp), rt_period_us);
++}
++
++static u64 cpu_rt_period_read_uint(struct cgroup *cgrp, struct cftype *cft)
++{
++ return sched_group_rt_period(cgroup_tg(cgrp));
++}
++#endif /* CONFIG_RT_GROUP_SCHED */
++
++static struct cftype cpu_files[] = {
++#ifdef CONFIG_FAIR_GROUP_SCHED
++ {
++ .name = "shares",
++ .read_u64 = cpu_shares_read_u64,
++ .write_u64 = cpu_shares_write_u64,
++ },
++#endif
++#ifdef CONFIG_RT_GROUP_SCHED
++ {
++ .name = "rt_runtime_us",
++ .read_s64 = cpu_rt_runtime_read,
++ .write_s64 = cpu_rt_runtime_write,
++ },
++ {
++ .name = "rt_period_us",
++ .read_u64 = cpu_rt_period_read_uint,
++ .write_u64 = cpu_rt_period_write_uint,
++ },
++#endif
++};
++
++static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
++{
++ return cgroup_add_files(cont, ss, cpu_files, ARRAY_SIZE(cpu_files));
++}
++
++struct cgroup_subsys cpu_cgroup_subsys = {
++ .name = "cpu",
++ .create = cpu_cgroup_create,
++ .destroy = cpu_cgroup_destroy,
++ .can_attach = cpu_cgroup_can_attach,
++ .attach = cpu_cgroup_attach,
++ .populate = cpu_cgroup_populate,
++ .subsys_id = cpu_cgroup_subsys_id,
++ .early_init = 1,
++};
++
++#endif /* CONFIG_CGROUP_SCHED */
++
++#ifdef CONFIG_CGROUP_CPUACCT
++
++/*
++ * CPU accounting code for task groups.
++ *
++ * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
++ * (balbir@in.ibm.com).
++ */
++
++/* track cpu usage of a group of tasks */
++struct cpuacct {
++ struct cgroup_subsys_state css;
++ /* cpuusage holds pointer to a u64-type object on every cpu */
++ u64 *cpuusage;
++};
++
++struct cgroup_subsys cpuacct_subsys;
++
++/* return cpu accounting group corresponding to this container */
++static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
++{
++ return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
++ struct cpuacct, css);
++}
++
++/* return cpu accounting group to which this task belongs */
++static inline struct cpuacct *task_ca(struct task_struct *tsk)
++{
++ return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
++ struct cpuacct, css);
++}
++
++/* create a new cpu accounting group */
++static struct cgroup_subsys_state *cpuacct_create(
++ struct cgroup_subsys *ss, struct cgroup *cgrp)
++{
++ struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
++
++ if (!ca)
++ return ERR_PTR(-ENOMEM);
++
++ ca->cpuusage = alloc_percpu(u64);
++ if (!ca->cpuusage) {
++ kfree(ca);
++ return ERR_PTR(-ENOMEM);
++ }
++
++ return &ca->css;
++}
++
++/* destroy an existing cpu accounting group */
++static void
++cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
++{
++ struct cpuacct *ca = cgroup_ca(cgrp);
++
++ free_percpu(ca->cpuusage);
++ kfree(ca);
++}
++
++/* return total cpu usage (in nanoseconds) of a group */
++static u64 cpuusage_read(struct cgroup *cgrp, struct cftype *cft)
++{
++ struct cpuacct *ca = cgroup_ca(cgrp);
++ u64 totalcpuusage = 0;
++ int i;
++
++ for_each_possible_cpu(i) {
++ u64 *cpuusage = percpu_ptr(ca->cpuusage, i);
++
++ /*
++ * Take rq->lock to make 64-bit addition safe on 32-bit
++ * platforms.
++ */
++ spin_lock_irq(&cpu_rq(i)->lock);
++ totalcpuusage += *cpuusage;
++ spin_unlock_irq(&cpu_rq(i)->lock);
++ }
++
++ return totalcpuusage;
++}
++
++static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype,
++ u64 reset)
++{
++ struct cpuacct *ca = cgroup_ca(cgrp);
++ int err = 0;
++ int i;
++
++ if (reset) {
++ err = -EINVAL;
++ goto out;
++ }
++
++ for_each_possible_cpu(i) {
++ u64 *cpuusage = percpu_ptr(ca->cpuusage, i);
++
++ spin_lock_irq(&cpu_rq(i)->lock);
++ *cpuusage = 0;
++ spin_unlock_irq(&cpu_rq(i)->lock);
++ }
++out:
++ return err;
++}
++
++static struct cftype files[] = {
++ {
++ .name = "usage",
++ .read_u64 = cpuusage_read,
++ .write_u64 = cpuusage_write,
++ },
++};
++
++static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
++{
++ return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files));
++}
++
++/*
++ * charge this task's execution time to its accounting group.
++ *
++ * called with rq->lock held.
++ */
++static void cpuacct_charge(struct task_struct *tsk, u64 cputime)
++{
++ struct cpuacct *ca;
++
++ if (!cpuacct_subsys.active)
++ return;
++
++ ca = task_ca(tsk);
++ if (ca) {
++ u64 *cpuusage = percpu_ptr(ca->cpuusage, task_cpu(tsk));
++
++ *cpuusage += cputime;
++ }
++}
++
++struct cgroup_subsys cpuacct_subsys = {
++ .name = "cpuacct",
++ .create = cpuacct_create,
++ .destroy = cpuacct_destroy,
++ .populate = cpuacct_populate,
++ .subsys_id = cpuacct_subsys_id,
++};
++#endif /* CONFIG_CGROUP_CPUACCT */
+diff -Nurb linux-2.6.27-590/kernel/sched.c.rej linux-2.6.27-591/kernel/sched.c.rej
+--- linux-2.6.27-590/kernel/sched.c.rej 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.27-591/kernel/sched.c.rej 2010-02-01 19:43:07.000000000 -0500
+@@ -0,0 +1,258 @@
++***************
++*** 23,28 ****
++ #include <linux/nmi.h>
++ #include <linux/init.h>
++ #include <asm/uaccess.h>
++ #include <linux/highmem.h>
++ #include <linux/smp_lock.h>
++ #include <asm/mmu_context.h>
++--- 23,29 ----
++ #include <linux/nmi.h>
++ #include <linux/init.h>
++ #include <asm/uaccess.h>
+++ #include <linux/arrays.h>
++ #include <linux/highmem.h>
++ #include <linux/smp_lock.h>
++ #include <asm/mmu_context.h>
++***************
++*** 451,456 ****
++
++ repeat_lock_task:
++ rq = task_rq(p);
++ spin_lock(&rq->lock);
++ if (unlikely(rq != task_rq(p))) {
++ spin_unlock(&rq->lock);
++--- 455,461 ----
++
++ repeat_lock_task:
++ rq = task_rq(p);
+++
++ spin_lock(&rq->lock);
++ if (unlikely(rq != task_rq(p))) {
++ spin_unlock(&rq->lock);
++***************
++*** 1761,1766 ****
++ * event cannot wake it up and insert it on the runqueue either.
++ */
++ p->state = TASK_RUNNING;
++
++ /*
++ * Make sure we do not leak PI boosting priority to the child:
++--- 1766,1786 ----
++ * event cannot wake it up and insert it on the runqueue either.
++ */
++ p->state = TASK_RUNNING;
+++ #ifdef CONFIG_CHOPSTIX
+++ /* The jiffy of last interruption */
+++ if (p->state & TASK_UNINTERRUPTIBLE) {
+++ p->last_interrupted=jiffies;
+++ }
+++ else
+++ if (p->state & TASK_INTERRUPTIBLE) {
+++ p->last_interrupted=INTERRUPTIBLE;
+++ }
+++ else
+++ p->last_interrupted=RUNNING;
+++
+++ /* The jiffy of last execution */
+++ p->last_ran_j=jiffies;
+++ #endif
++
++ /*
++ * Make sure we do not leak PI boosting priority to the child:
++***************
++*** 3628,3633 ****
++
++ #endif
++
++ static inline int interactive_sleep(enum sleep_type sleep_type)
++ {
++ return (sleep_type == SLEEP_INTERACTIVE ||
++--- 3648,3654 ----
++
++ #endif
++
+++
++ static inline int interactive_sleep(enum sleep_type sleep_type)
++ {
++ return (sleep_type == SLEEP_INTERACTIVE ||
++***************
++*** 3637,3652 ****
++ /*
++ * schedule() is the main scheduler function.
++ */
++ asmlinkage void __sched schedule(void)
++ {
++ struct task_struct *prev, *next;
++ struct prio_array *array;
++ struct list_head *queue;
++ unsigned long long now;
++- unsigned long run_time;
++ int cpu, idx, new_prio;
++ long *switch_count;
++ struct rq *rq;
++
++ /*
++ * Test if we are atomic. Since do_exit() needs to call into
++--- 3658,3685 ----
++ /*
++ * schedule() is the main scheduler function.
++ */
+++
+++ #ifdef CONFIG_CHOPSTIX
+++ extern void (*rec_event)(void *,unsigned int);
+++ struct event_spec {
+++ unsigned long pc;
+++ unsigned long dcookie;
+++ unsigned int count;
+++ unsigned int reason;
+++ };
+++ #endif
+++
++ asmlinkage void __sched schedule(void)
++ {
++ struct task_struct *prev, *next;
++ struct prio_array *array;
++ struct list_head *queue;
++ unsigned long long now;
+++ unsigned long run_time, diff;
++ int cpu, idx, new_prio;
++ long *switch_count;
++ struct rq *rq;
+++ int sampling_reason;
++
++ /*
++ * Test if we are atomic. Since do_exit() needs to call into
++***************
++*** 3700,3705 ****
++ switch_count = &prev->nivcsw;
++ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
++ switch_count = &prev->nvcsw;
++ if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
++ unlikely(signal_pending(prev))))
++ prev->state = TASK_RUNNING;
++--- 3733,3739 ----
++ switch_count = &prev->nivcsw;
++ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
++ switch_count = &prev->nvcsw;
+++
++ if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
++ unlikely(signal_pending(prev))))
++ prev->state = TASK_RUNNING;
++***************
++*** 3709,3714 ****
++ vx_uninterruptible_inc(prev);
++ }
++ deactivate_task(prev, rq);
++ }
++ }
++
++--- 3743,3759 ----
++ vx_uninterruptible_inc(prev);
++ }
++ deactivate_task(prev, rq);
+++ #ifdef CONFIG_CHOPSTIX
+++ /* An uninterruptible process just yielded. Record the current jiffie */
+++ if (prev->state & TASK_UNINTERRUPTIBLE) {
+++ prev->last_interrupted=jiffies;
+++ }
+++ /* An interruptible process just yielded, or it got preempted.
+++ * Mark it as interruptible */
+++ else if (prev->state & TASK_INTERRUPTIBLE) {
+++ prev->last_interrupted=INTERRUPTIBLE;
+++ }
+++ #endif
++ }
++ }
++
++***************
++*** 3785,3790 ****
++ prev->sleep_avg = 0;
++ prev->timestamp = prev->last_ran = now;
++
++ sched_info_switch(prev, next);
++ if (likely(prev != next)) {
++ next->timestamp = next->last_ran = now;
++--- 3830,3869 ----
++ prev->sleep_avg = 0;
++ prev->timestamp = prev->last_ran = now;
++
+++ #ifdef CONFIG_CHOPSTIX
+++ /* Run only if the Chopstix module so decrees it */
+++ if (rec_event) {
+++ prev->last_ran_j = jiffies;
+++ if (next->last_interrupted!=INTERRUPTIBLE) {
+++ if (next->last_interrupted!=RUNNING) {
+++ diff = (jiffies-next->last_interrupted);
+++ sampling_reason = 0;/* BLOCKING */
+++ }
+++ else {
+++ diff = jiffies-next->last_ran_j;
+++ sampling_reason = 1;/* PREEMPTION */
+++ }
+++
+++ if (diff >= HZ/10) {
+++ struct event event;
+++ struct event_spec espec;
+++ struct pt_regs *regs;
+++ regs = task_pt_regs(current);
+++
+++ espec.reason = sampling_reason;
+++ event.event_data=&espec;
+++ event.task=next;
+++ espec.pc=regs->eip;
+++ event.event_type=2;
+++ /* index in the event array currently set up */
+++ /* make sure the counters are loaded in the order we want them to show up*/
+++ (*rec_event)(&event, diff);
+++ }
+++ }
+++ /* next has been elected to run */
+++ next->last_interrupted=0;
+++ }
+++ #endif
++ sched_info_switch(prev, next);
++ if (likely(prev != next)) {
++ next->timestamp = next->last_ran = now;
++***************
++*** 5737,5742 ****
++ jiffies_to_timespec(p->policy == SCHED_FIFO ?
++ 0 : task_timeslice(p), &t);
++ read_unlock(&tasklist_lock);
++ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
++ out_nounlock:
++ return retval;
++--- 5817,5823 ----
++ jiffies_to_timespec(p->policy == SCHED_FIFO ?
++ 0 : task_timeslice(p), &t);
++ read_unlock(&tasklist_lock);
+++
++ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
++ out_nounlock:
++ return retval;
++***************
++*** 7980,7982 ****
++ }
++
++ #endif
++--- 8061,8080 ----
++ }
++
++ #endif
+++
+++ #ifdef CONFIG_CHOPSTIX
+++ void (*rec_event)(void *,unsigned int) = NULL;
+++
+++ /* To support safe calling from asm */
+++ asmlinkage void rec_event_asm (struct event *event_signature_in, unsigned int count) {
+++ struct pt_regs *regs;
+++ struct event_spec *es = event_signature_in->event_data;
+++ regs = task_pt_regs(current);
+++ event_signature_in->task=current;
+++ es->pc=regs->eip;
+++ event_signature_in->count=1;
+++ (*rec_event)(event_signature_in, count);
+++ }
+++ EXPORT_SYMBOL(rec_event);
+++ EXPORT_SYMBOL(in_sched_functions);
+++ #endif
+diff -Nurb linux-2.6.27-590/mm/memory.c linux-2.6.27-591/mm/memory.c
+--- linux-2.6.27-590/mm/memory.c 2010-02-01 19:42:07.000000000 -0500
++++ linux-2.6.27-591/mm/memory.c 2010-02-01 19:43:07.000000000 -0500
+@@ -61,6 +61,7 @@
+
+ #include <linux/swapops.h>
+ #include <linux/elf.h>
++#include <linux/arrays.h>
+
+ #include "internal.h"
+
+@@ -2690,6 +2691,15 @@
+ return ret;
+ }
+
++extern void (*rec_event)(void *,unsigned int);
++struct event_spec {
++ unsigned long pc;
++ unsigned long dcookie;
++ unsigned count;
++ unsigned char reason;
++};
++
++
+ /*
+ * By the time we get here, we already hold the mm semaphore
+ */
+@@ -2719,6 +2729,24 @@
+ if (!pte)
+ return VM_FAULT_OOM;
+
++#ifdef CONFIG_CHOPSTIX
++ if (rec_event) {
++ struct event event;
++ struct event_spec espec;
++ struct pt_regs *regs;
++ unsigned int pc;
++ regs = task_pt_regs(current);
++ pc = regs->ip & (unsigned int) ~4095;
++
++ espec.reason = 0; /* alloc */
++ event.event_data=&espec;
++ event.task = current;
++ espec.pc=pc;
++ event.event_type=5;
++ (*rec_event)(&event, 1);
++ }
++#endif
++
+ return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
+ }
+
+diff -Nurb linux-2.6.27-590/mm/memory.c.orig linux-2.6.27-591/mm/memory.c.orig
+--- linux-2.6.27-590/mm/memory.c.orig 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.27-591/mm/memory.c.orig 2010-02-01 19:42:07.000000000 -0500
+@@ -0,0 +1,3035 @@
++/*
++ * linux/mm/memory.c
++ *
++ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
++ */
++
++/*
++ * demand-loading started 01.12.91 - seems it is high on the list of
++ * things wanted, and it should be easy to implement. - Linus
++ */
++
++/*
++ * Ok, demand-loading was easy, shared pages a little bit tricker. Shared
++ * pages started 02.12.91, seems to work. - Linus.
++ *
++ * Tested sharing by executing about 30 /bin/sh: under the old kernel it
++ * would have taken more than the 6M I have free, but it worked well as
++ * far as I could see.
++ *
++ * Also corrected some "invalidate()"s - I wasn't doing enough of them.
++ */
++
++/*
++ * Real VM (paging to/from disk) started 18.12.91. Much more work and
++ * thought has to go into this. Oh, well..
++ * 19.12.91 - works, somewhat. Sometimes I get faults, don't know why.
++ * Found it. Everything seems to work now.
++ * 20.12.91 - Ok, making the swap-device changeable like the root.
++ */
++
++/*
++ * 05.04.94 - Multi-page memory management added for v1.1.
++ * Idea by Alex Bligh (alex@cconcepts.co.uk)
++ *
++ * 16.07.99 - Support of BIGMEM added by Gerhard Wichert, Siemens AG
++ * (Gerhard.Wichert@pdb.siemens.de)
++ *
++ * Aug/Sep 2004 Changed to four level page tables (Andi Kleen)
++ */
++
++#include <linux/kernel_stat.h>
++#include <linux/mm.h>
++#include <linux/hugetlb.h>
++#include <linux/mman.h>
++#include <linux/swap.h>
++#include <linux/highmem.h>
++#include <linux/pagemap.h>
++#include <linux/rmap.h>
++#include <linux/module.h>
++#include <linux/delayacct.h>
++#include <linux/init.h>
++#include <linux/writeback.h>
++#include <linux/memcontrol.h>
++#include <linux/mmu_notifier.h>
++
++#include <asm/pgalloc.h>
++#include <asm/uaccess.h>
++#include <asm/tlb.h>
++#include <asm/tlbflush.h>
++#include <asm/pgtable.h>
++
++#include <linux/swapops.h>
++#include <linux/elf.h>
++
++#include "internal.h"
++
++#ifndef CONFIG_NEED_MULTIPLE_NODES
++/* use the per-pgdat data instead for discontigmem - mbligh */
++unsigned long max_mapnr;
++struct page *mem_map;
++
++EXPORT_SYMBOL(max_mapnr);
++EXPORT_SYMBOL(mem_map);
++#endif
++
++unsigned long num_physpages;
++/*
++ * A number of key systems in x86 including ioremap() rely on the assumption
++ * that high_memory defines the upper bound on direct map memory, then end
++ * of ZONE_NORMAL. Under CONFIG_DISCONTIG this means that max_low_pfn and
++ * highstart_pfn must be the same; there must be no gap between ZONE_NORMAL
++ * and ZONE_HIGHMEM.
++ */
++void * high_memory;
++
++EXPORT_SYMBOL(num_physpages);
++EXPORT_SYMBOL(high_memory);
++
++/*
++ * Randomize the address space (stacks, mmaps, brk, etc.).
++ *
++ * ( When CONFIG_COMPAT_BRK=y we exclude brk from randomization,
++ * as ancient (libc5 based) binaries can segfault. )
++ */
++int randomize_va_space __read_mostly =
++#ifdef CONFIG_COMPAT_BRK
++ 1;
++#else
++ 2;
++#endif
++
++static int __init disable_randmaps(char *s)
++{
++ randomize_va_space = 0;
++ return 1;
++}
++__setup("norandmaps", disable_randmaps);
++
++
++/*
++ * If a p?d_bad entry is found while walking page tables, report
++ * the error, before resetting entry to p?d_none. Usually (but
++ * very seldom) called out from the p?d_none_or_clear_bad macros.
++ */
++
++void pgd_clear_bad(pgd_t *pgd)
++{
++ pgd_ERROR(*pgd);
++ pgd_clear(pgd);
++}
++
++void pud_clear_bad(pud_t *pud)
++{
++ pud_ERROR(*pud);
++ pud_clear(pud);
++}
++
++void pmd_clear_bad(pmd_t *pmd)
++{
++ pmd_ERROR(*pmd);
++ pmd_clear(pmd);
++}
++
++/*
++ * Note: this doesn't free the actual pages themselves. That
++ * has been handled earlier when unmapping all the memory regions.
++ */
++static void free_pte_range(struct mmu_gather *tlb, pmd_t *pmd)
++{
++ pgtable_t token = pmd_pgtable(*pmd);
++ pmd_clear(pmd);
++ pte_free_tlb(tlb, token);
++ tlb->mm->nr_ptes--;
++}
++
++static inline void free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
++ unsigned long addr, unsigned long end,
++ unsigned long floor, unsigned long ceiling)
++{
++ pmd_t *pmd;
++ unsigned long next;
++ unsigned long start;
++
++ start = addr;
++ pmd = pmd_offset(pud, addr);
++ do {
++ next = pmd_addr_end(addr, end);
++ if (pmd_none_or_clear_bad(pmd))
++ continue;
++ free_pte_range(tlb, pmd);
++ } while (pmd++, addr = next, addr != end);
++
++ start &= PUD_MASK;
++ if (start < floor)
++ return;
++ if (ceiling) {
++ ceiling &= PUD_MASK;
++ if (!ceiling)
++ return;
++ }
++ if (end - 1 > ceiling - 1)
++ return;
++
++ pmd = pmd_offset(pud, start);
++ pud_clear(pud);
++ pmd_free_tlb(tlb, pmd);
++}
++
++static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
++ unsigned long addr, unsigned long end,
++ unsigned long floor, unsigned long ceiling)
++{
++ pud_t *pud;
++ unsigned long next;
++ unsigned long start;
++
++ start = addr;
++ pud = pud_offset(pgd, addr);
++ do {
++ next = pud_addr_end(addr, end);
++ if (pud_none_or_clear_bad(pud))
++ continue;
++ free_pmd_range(tlb, pud, addr, next, floor, ceiling);
++ } while (pud++, addr = next, addr != end);
++
++ start &= PGDIR_MASK;
++ if (start < floor)
++ return;
++ if (ceiling) {
++ ceiling &= PGDIR_MASK;
++ if (!ceiling)
++ return;
++ }
++ if (end - 1 > ceiling - 1)
++ return;
++
++ pud = pud_offset(pgd, start);
++ pgd_clear(pgd);
++ pud_free_tlb(tlb, pud);
++}
++
++/*
++ * This function frees user-level page tables of a process.
++ *
++ * Must be called with pagetable lock held.
++ */
++void free_pgd_range(struct mmu_gather *tlb,
++ unsigned long addr, unsigned long end,
++ unsigned long floor, unsigned long ceiling)
++{
++ pgd_t *pgd;
++ unsigned long next;
++ unsigned long start;
++
++ /*
++ * The next few lines have given us lots of grief...
++ *
++ * Why are we testing PMD* at this top level? Because often
++ * there will be no work to do at all, and we'd prefer not to
++ * go all the way down to the bottom just to discover that.
++ *
++ * Why all these "- 1"s? Because 0 represents both the bottom
++ * of the address space and the top of it (using -1 for the
++ * top wouldn't help much: the masks would do the wrong thing).
++ * The rule is that addr 0 and floor 0 refer to the bottom of
++ * the address space, but end 0 and ceiling 0 refer to the top
++ * Comparisons need to use "end - 1" and "ceiling - 1" (though
++ * that end 0 case should be mythical).
++ *
++ * Wherever addr is brought up or ceiling brought down, we must
++ * be careful to reject "the opposite 0" before it confuses the
++ * subsequent tests. But what about where end is brought down
++ * by PMD_SIZE below? no, end can't go down to 0 there.
++ *
++ * Whereas we round start (addr) and ceiling down, by different
++ * masks at different levels, in order to test whether a table
++ * now has no other vmas using it, so can be freed, we don't
++ * bother to round floor or end up - the tests don't need that.
++ */
++
++ addr &= PMD_MASK;
++ if (addr < floor) {
++ addr += PMD_SIZE;
++ if (!addr)
++ return;
++ }
++ if (ceiling) {
++ ceiling &= PMD_MASK;
++ if (!ceiling)
++ return;
++ }
++ if (end - 1 > ceiling - 1)
++ end -= PMD_SIZE;
++ if (addr > end - 1)
++ return;
++
++ start = addr;
++ pgd = pgd_offset(tlb->mm, addr);
++ do {
++ next = pgd_addr_end(addr, end);
++ if (pgd_none_or_clear_bad(pgd))
++ continue;
++ free_pud_range(tlb, pgd, addr, next, floor, ceiling);
++ } while (pgd++, addr = next, addr != end);
++}
++
++void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
++ unsigned long floor, unsigned long ceiling)
++{
++ while (vma) {
++ struct vm_area_struct *next = vma->vm_next;
++ unsigned long addr = vma->vm_start;
++
++ /*
++ * Hide vma from rmap and vmtruncate before freeing pgtables
++ */
++ anon_vma_unlink(vma);
++ unlink_file_vma(vma);
++
++ if (is_vm_hugetlb_page(vma)) {
++ hugetlb_free_pgd_range(tlb, addr, vma->vm_end,
++ floor, next? next->vm_start: ceiling);
++ } else {
++ /*
++ * Optimization: gather nearby vmas into one call down
++ */
++ while (next && next->vm_start <= vma->vm_end + PMD_SIZE
++ && !is_vm_hugetlb_page(next)) {
++ vma = next;
++ next = vma->vm_next;
++ anon_vma_unlink(vma);
++ unlink_file_vma(vma);
++ }
++ free_pgd_range(tlb, addr, vma->vm_end,
++ floor, next? next->vm_start: ceiling);
++ }
++ vma = next;
++ }
++}
++
++int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
++{
++ pgtable_t new = pte_alloc_one(mm, address);
++ if (!new)
++ return -ENOMEM;
++
++ /*
++ * Ensure all pte setup (eg. pte page lock and page clearing) are
++ * visible before the pte is made visible to other CPUs by being
++ * put into page tables.
++ *
++ * The other side of the story is the pointer chasing in the page
++ * table walking code (when walking the page table without locking;
++ * ie. most of the time). Fortunately, these data accesses consist
++ * of a chain of data-dependent loads, meaning most CPUs (alpha
++ * being the notable exception) will already guarantee loads are
++ * seen in-order. See the alpha page table accessors for the
++ * smp_read_barrier_depends() barriers in page table walking code.
++ */
++ smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */
++
++ spin_lock(&mm->page_table_lock);
++ if (!pmd_present(*pmd)) { /* Has another populated it ? */
++ mm->nr_ptes++;
++ pmd_populate(mm, pmd, new);
++ new = NULL;
++ }
++ spin_unlock(&mm->page_table_lock);
++ if (new)
++ pte_free(mm, new);
++ return 0;
++}
++
++int __pte_alloc_kernel(pmd_t *pmd, unsigned long address)
++{
++ pte_t *new = pte_alloc_one_kernel(&init_mm, address);
++ if (!new)
++ return -ENOMEM;
++
++ smp_wmb(); /* See comment in __pte_alloc */
++
++ spin_lock(&init_mm.page_table_lock);
++ if (!pmd_present(*pmd)) { /* Has another populated it ? */
++ pmd_populate_kernel(&init_mm, pmd, new);
++ new = NULL;
++ }
++ spin_unlock(&init_mm.page_table_lock);
++ if (new)
++ pte_free_kernel(&init_mm, new);
++ return 0;
++}
++
++static inline void add_mm_rss(struct mm_struct *mm, int file_rss, int anon_rss)
++{
++ if (file_rss)
++ add_mm_counter(mm, file_rss, file_rss);
++ if (anon_rss)
++ add_mm_counter(mm, anon_rss, anon_rss);
++}
++
++/*
++ * This function is called to print an error when a bad pte
++ * is found. For example, we might have a PFN-mapped pte in
++ * a region that doesn't allow it.
++ *
++ * The calling function must still handle the error.
++ */
++static void print_bad_pte(struct vm_area_struct *vma, pte_t pte,
++ unsigned long vaddr)
++{
++ printk(KERN_ERR "Bad pte = %08llx, process = %s, "
++ "vm_flags = %lx, vaddr = %lx\n",
++ (long long)pte_val(pte),
++ (vma->vm_mm == current->mm ? current->comm : "???"),
++ vma->vm_flags, vaddr);
++ dump_stack();
++}
++
++static inline int is_cow_mapping(unsigned int flags)
++{
++ return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
++}
++
++/*
++ * vm_normal_page -- This function gets the "struct page" associated with a pte.
++ *
++ * "Special" mappings do not wish to be associated with a "struct page" (either
++ * it doesn't exist, or it exists but they don't want to touch it). In this
++ * case, NULL is returned here. "Normal" mappings do have a struct page.
++ *
++ * There are 2 broad cases. Firstly, an architecture may define a pte_special()
++ * pte bit, in which case this function is trivial. Secondly, an architecture
++ * may not have a spare pte bit, which requires a more complicated scheme,
++ * described below.
++ *
++ * A raw VM_PFNMAP mapping (ie. one that is not COWed) is always considered a
++ * special mapping (even if there are underlying and valid "struct pages").
++ * COWed pages of a VM_PFNMAP are always normal.
++ *
++ * The way we recognize COWed pages within VM_PFNMAP mappings is through the
++ * rules set up by "remap_pfn_range()": the vma will have the VM_PFNMAP bit
++ * set, and the vm_pgoff will point to the first PFN mapped: thus every special
++ * mapping will always honor the rule
++ *
++ * pfn_of_page == vma->vm_pgoff + ((addr - vma->vm_start) >> PAGE_SHIFT)
++ *
++ * And for normal mappings this is false.
++ *
++ * This restricts such mappings to be a linear translation from virtual address
++ * to pfn. To get around this restriction, we allow arbitrary mappings so long
++ * as the vma is not a COW mapping; in that case, we know that all ptes are
++ * special (because none can have been COWed).
++ *
++ *
++ * In order to support COW of arbitrary special mappings, we have VM_MIXEDMAP.
++ *
++ * VM_MIXEDMAP mappings can likewise contain memory with or without "struct
++ * page" backing, however the difference is that _all_ pages with a struct
++ * page (that is, those where pfn_valid is true) are refcounted and considered
++ * normal pages by the VM. The disadvantage is that pages are refcounted
++ * (which can be slower and simply not an option for some PFNMAP users). The
++ * advantage is that we don't have to follow the strict linearity rule of
++ * PFNMAP mappings in order to support COWable mappings.
++ *
++ */
++#ifdef __HAVE_ARCH_PTE_SPECIAL
++# define HAVE_PTE_SPECIAL 1
++#else
++# define HAVE_PTE_SPECIAL 0
++#endif
++struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
++ pte_t pte)
++{
++ unsigned long pfn;
++
++ if (HAVE_PTE_SPECIAL) {
++ if (likely(!pte_special(pte))) {
++ VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
++ return pte_page(pte);
++ }
++ VM_BUG_ON(!(vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
++ return NULL;
++ }
++
++ /* !HAVE_PTE_SPECIAL case follows: */
++
++ pfn = pte_pfn(pte);
++
++ if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
++ if (vma->vm_flags & VM_MIXEDMAP) {
++ if (!pfn_valid(pfn))
++ return NULL;
++ goto out;
++ } else {
++ unsigned long off;
++ off = (addr - vma->vm_start) >> PAGE_SHIFT;
++ if (pfn == vma->vm_pgoff + off)
++ return NULL;
++ if (!is_cow_mapping(vma->vm_flags))
++ return NULL;
++ }
++ }
++
++ VM_BUG_ON(!pfn_valid(pfn));
++
++ /*
++ * NOTE! We still have PageReserved() pages in the page tables.
++ *
++ * eg. VDSO mappings can cause them to exist.
++ */
++out:
++ return pfn_to_page(pfn);
++}
++
++/*
++ * copy one vm_area from one task to the other. Assumes the page tables
++ * already present in the new task to be cleared in the whole range
++ * covered by this vma.
++ */
++
++static inline void
++copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
++ pte_t *dst_pte, pte_t *src_pte, struct vm_area_struct *vma,
++ unsigned long addr, int *rss)
++{
++ unsigned long vm_flags = vma->vm_flags;
++ pte_t pte = *src_pte;
++ struct page *page;
++
++ /* pte contains position in swap or file, so copy. */
++ if (unlikely(!pte_present(pte))) {
++ if (!pte_file(pte)) {
++ swp_entry_t entry = pte_to_swp_entry(pte);
++
++ swap_duplicate(entry);
++ /* make sure dst_mm is on swapoff's mmlist. */
++ if (unlikely(list_empty(&dst_mm->mmlist))) {
++ spin_lock(&mmlist_lock);
++ if (list_empty(&dst_mm->mmlist))
++ list_add(&dst_mm->mmlist,
++ &src_mm->mmlist);
++ spin_unlock(&mmlist_lock);
++ }
++ if (is_write_migration_entry(entry) &&
++ is_cow_mapping(vm_flags)) {
++ /*
++ * COW mappings require pages in both parent
++ * and child to be set to read.
++ */
++ make_migration_entry_read(&entry);
++ pte = swp_entry_to_pte(entry);
++ set_pte_at(src_mm, addr, src_pte, pte);
++ }
++ }
++ goto out_set_pte;
++ }
++
++ /*
++ * If it's a COW mapping, write protect it both
++ * in the parent and the child
++ */
++ if (is_cow_mapping(vm_flags)) {
++ ptep_set_wrprotect(src_mm, addr, src_pte);
++ pte = pte_wrprotect(pte);
++ }
++
++ /*
++ * If it's a shared mapping, mark it clean in
++ * the child
++ */
++ if (vm_flags & VM_SHARED)
++ pte = pte_mkclean(pte);
++ pte = pte_mkold(pte);
++
++ page = vm_normal_page(vma, addr, pte);
++ if (page) {
++ get_page(page);
++ page_dup_rmap(page, vma, addr);
++ rss[!!PageAnon(page)]++;
++ }
++
++out_set_pte:
++ set_pte_at(dst_mm, addr, dst_pte, pte);
++}
++
++static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
++ pmd_t *dst_pmd, pmd_t *src_pmd, struct vm_area_struct *vma,
++ unsigned long addr, unsigned long end)
++{
++ pte_t *src_pte, *dst_pte;
++ spinlock_t *src_ptl, *dst_ptl;
++ int progress = 0;
++ int rss[2];
++
++ if (!vx_rss_avail(dst_mm, ((end - addr)/PAGE_SIZE + 1)))
++ return -ENOMEM;
++
++again:
++ rss[1] = rss[0] = 0;
++ dst_pte = pte_alloc_map_lock(dst_mm, dst_pmd, addr, &dst_ptl);
++ if (!dst_pte)
++ return -ENOMEM;
++ src_pte = pte_offset_map_nested(src_pmd, addr);
++ src_ptl = pte_lockptr(src_mm, src_pmd);
++ spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
++ arch_enter_lazy_mmu_mode();
++
++ do {
++ /*
++ * We are holding two locks at this point - either of them
++ * could generate latencies in another task on another CPU.
++ */
++ if (progress >= 32) {
++ progress = 0;
++ if (need_resched() ||
++ spin_needbreak(src_ptl) || spin_needbreak(dst_ptl))
++ break;
++ }
++ if (pte_none(*src_pte)) {
++ progress++;
++ continue;
++ }
++ copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, vma, addr, rss);
++ progress += 8;
++ } while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end);
++
++ arch_leave_lazy_mmu_mode();
++ spin_unlock(src_ptl);
++ pte_unmap_nested(src_pte - 1);
++ add_mm_rss(dst_mm, rss[0], rss[1]);
++ pte_unmap_unlock(dst_pte - 1, dst_ptl);
++ cond_resched();
++ if (addr != end)
++ goto again;
++ return 0;
++}
++
++static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
++ pud_t *dst_pud, pud_t *src_pud, struct vm_area_struct *vma,
++ unsigned long addr, unsigned long end)
++{
++ pmd_t *src_pmd, *dst_pmd;
++ unsigned long next;
++
++ dst_pmd = pmd_alloc(dst_mm, dst_pud, addr);
++ if (!dst_pmd)
++ return -ENOMEM;
++ src_pmd = pmd_offset(src_pud, addr);
++ do {
++ next = pmd_addr_end(addr, end);
++ if (pmd_none_or_clear_bad(src_pmd))
++ continue;
++ if (copy_pte_range(dst_mm, src_mm, dst_pmd, src_pmd,
++ vma, addr, next))
++ return -ENOMEM;
++ } while (dst_pmd++, src_pmd++, addr = next, addr != end);
++ return 0;
++}
++
++static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
++ pgd_t *dst_pgd, pgd_t *src_pgd, struct vm_area_struct *vma,
++ unsigned long addr, unsigned long end)
++{
++ pud_t *src_pud, *dst_pud;
++ unsigned long next;
++
++ dst_pud = pud_alloc(dst_mm, dst_pgd, addr);
++ if (!dst_pud)
++ return -ENOMEM;
++ src_pud = pud_offset(src_pgd, addr);
++ do {
++ next = pud_addr_end(addr, end);
++ if (pud_none_or_clear_bad(src_pud))
++ continue;
++ if (copy_pmd_range(dst_mm, src_mm, dst_pud, src_pud,
++ vma, addr, next))
++ return -ENOMEM;
++ } while (dst_pud++, src_pud++, addr = next, addr != end);
++ return 0;
++}
++
++int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
++ struct vm_area_struct *vma)
++{
++ pgd_t *src_pgd, *dst_pgd;
++ unsigned long next;
++ unsigned long addr = vma->vm_start;
++ unsigned long end = vma->vm_end;
++ int ret;
++
++ /*
++ * Don't copy ptes where a page fault will fill them correctly.
++ * Fork becomes much lighter when there are big shared or private
++ * readonly mappings. The tradeoff is that copy_page_range is more
++ * efficient than faulting.
++ */
++ if (!(vma->vm_flags & (VM_HUGETLB|VM_NONLINEAR|VM_PFNMAP|VM_INSERTPAGE))) {
++ if (!vma->anon_vma)
++ return 0;
++ }
++
++ if (is_vm_hugetlb_page(vma))
++ return copy_hugetlb_page_range(dst_mm, src_mm, vma);
++
++ /*
++ * We need to invalidate the secondary MMU mappings only when
++ * there could be a permission downgrade on the ptes of the
++ * parent mm. And a permission downgrade will only happen if
++ * is_cow_mapping() returns true.
++ */
++ if (is_cow_mapping(vma->vm_flags))
++ mmu_notifier_invalidate_range_start(src_mm, addr, end);
++
++ ret = 0;
++ dst_pgd = pgd_offset(dst_mm, addr);
++ src_pgd = pgd_offset(src_mm, addr);
++ do {
++ next = pgd_addr_end(addr, end);
++ if (pgd_none_or_clear_bad(src_pgd))
++ continue;
++ if (unlikely(copy_pud_range(dst_mm, src_mm, dst_pgd, src_pgd,
++ vma, addr, next))) {
++ ret = -ENOMEM;
++ break;
++ }
++ } while (dst_pgd++, src_pgd++, addr = next, addr != end);
++
++ if (is_cow_mapping(vma->vm_flags))
++ mmu_notifier_invalidate_range_end(src_mm,
++ vma->vm_start, end);
++ return ret;
++}
++
++static unsigned long zap_pte_range(struct mmu_gather *tlb,
++ struct vm_area_struct *vma, pmd_t *pmd,
++ unsigned long addr, unsigned long end,
++ long *zap_work, struct zap_details *details)
++{
++ struct mm_struct *mm = tlb->mm;
++ pte_t *pte;
++ spinlock_t *ptl;
++ int file_rss = 0;
++ int anon_rss = 0;
++
++ pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
++ arch_enter_lazy_mmu_mode();
++ do {
++ pte_t ptent = *pte;
++ if (pte_none(ptent)) {
++ (*zap_work)--;
++ continue;
++ }
++
++ (*zap_work) -= PAGE_SIZE;
++
++ if (pte_present(ptent)) {
++ struct page *page;
++
++ page = vm_normal_page(vma, addr, ptent);
++ if (unlikely(details) && page) {
++ /*
++ * unmap_shared_mapping_pages() wants to
++ * invalidate cache without truncating:
++ * unmap shared but keep private pages.
++ */
++ if (details->check_mapping &&
++ details->check_mapping != page->mapping)
++ continue;
++ /*
++ * Each page->index must be checked when
++ * invalidating or truncating nonlinear.
++ */
++ if (details->nonlinear_vma &&
++ (page->index < details->first_index ||
++ page->index > details->last_index))
++ continue;
++ }
++ ptent = ptep_get_and_clear_full(mm, addr, pte,
++ tlb->fullmm);
++ tlb_remove_tlb_entry(tlb, pte, addr);
++ if (unlikely(!page))
++ continue;
++ if (unlikely(details) && details->nonlinear_vma
++ && linear_page_index(details->nonlinear_vma,
++ addr) != page->index)
++ set_pte_at(mm, addr, pte,
++ pgoff_to_pte(page->index));
++ if (PageAnon(page))
++ anon_rss--;
++ else {
++ if (pte_dirty(ptent))
++ set_page_dirty(page);
++ if (pte_young(ptent))
++ SetPageReferenced(page);
++ file_rss--;
++ }
++ page_remove_rmap(page, vma);
++ tlb_remove_page(tlb, page);
++ continue;
++ }
++ /*
++ * If details->check_mapping, we leave swap entries;
++ * if details->nonlinear_vma, we leave file entries.
++ */
++ if (unlikely(details))
++ continue;
++ if (!pte_file(ptent))
++ free_swap_and_cache(pte_to_swp_entry(ptent));
++ pte_clear_not_present_full(mm, addr, pte, tlb->fullmm);
++ } while (pte++, addr += PAGE_SIZE, (addr != end && *zap_work > 0));
++
++ add_mm_rss(mm, file_rss, anon_rss);
++ arch_leave_lazy_mmu_mode();
++ pte_unmap_unlock(pte - 1, ptl);
++
++ return addr;
++}
++
++static inline unsigned long zap_pmd_range(struct mmu_gather *tlb,
++ struct vm_area_struct *vma, pud_t *pud,
++ unsigned long addr, unsigned long end,
++ long *zap_work, struct zap_details *details)
++{
++ pmd_t *pmd;
++ unsigned long next;
++
++ pmd = pmd_offset(pud, addr);
++ do {
++ next = pmd_addr_end(addr, end);
++ if (pmd_none_or_clear_bad(pmd)) {
++ (*zap_work)--;
++ continue;
++ }
++ next = zap_pte_range(tlb, vma, pmd, addr, next,
++ zap_work, details);
++ } while (pmd++, addr = next, (addr != end && *zap_work > 0));
++
++ return addr;
++}
++
++static inline unsigned long zap_pud_range(struct mmu_gather *tlb,
++ struct vm_area_struct *vma, pgd_t *pgd,
++ unsigned long addr, unsigned long end,
++ long *zap_work, struct zap_details *details)
++{
++ pud_t *pud;
++ unsigned long next;
++
++ pud = pud_offset(pgd, addr);
++ do {
++ next = pud_addr_end(addr, end);
++ if (pud_none_or_clear_bad(pud)) {
++ (*zap_work)--;
++ continue;
++ }
++ next = zap_pmd_range(tlb, vma, pud, addr, next,
++ zap_work, details);
++ } while (pud++, addr = next, (addr != end && *zap_work > 0));
++
++ return addr;
++}
++
++static unsigned long unmap_page_range(struct mmu_gather *tlb,
++ struct vm_area_struct *vma,
++ unsigned long addr, unsigned long end,
++ long *zap_work, struct zap_details *details)
++{
++ pgd_t *pgd;
++ unsigned long next;
++
++ if (details && !details->check_mapping && !details->nonlinear_vma)
++ details = NULL;
++
++ BUG_ON(addr >= end);
++ tlb_start_vma(tlb, vma);
++ pgd = pgd_offset(vma->vm_mm, addr);
++ do {
++ next = pgd_addr_end(addr, end);
++ if (pgd_none_or_clear_bad(pgd)) {
++ (*zap_work)--;
++ continue;
++ }
++ next = zap_pud_range(tlb, vma, pgd, addr, next,
++ zap_work, details);
++ } while (pgd++, addr = next, (addr != end && *zap_work > 0));
++ tlb_end_vma(tlb, vma);
++
++ return addr;
++}
++
++#ifdef CONFIG_PREEMPT
++# define ZAP_BLOCK_SIZE (8 * PAGE_SIZE)
++#else
++/* No preempt: go for improved straight-line efficiency */
++# define ZAP_BLOCK_SIZE (1024 * PAGE_SIZE)
++#endif
++
++/**
++ * unmap_vmas - unmap a range of memory covered by a list of vma's
++ * @tlbp: address of the caller's struct mmu_gather
++ * @vma: the starting vma
++ * @start_addr: virtual address at which to start unmapping
++ * @end_addr: virtual address at which to end unmapping
++ * @nr_accounted: Place number of unmapped pages in vm-accountable vma's here
++ * @details: details of nonlinear truncation or shared cache invalidation
++ *
++ * Returns the end address of the unmapping (restart addr if interrupted).
++ *
++ * Unmap all pages in the vma list.
++ *
++ * We aim to not hold locks for too long (for scheduling latency reasons).
++ * So zap pages in ZAP_BLOCK_SIZE bytecounts. This means we need to
++ * return the ending mmu_gather to the caller.
++ *
++ * Only addresses between `start' and `end' will be unmapped.
++ *
++ * The VMA list must be sorted in ascending virtual address order.
++ *
++ * unmap_vmas() assumes that the caller will flush the whole unmapped address
++ * range after unmap_vmas() returns. So the only responsibility here is to
++ * ensure that any thus-far unmapped pages are flushed before unmap_vmas()
++ * drops the lock and schedules.
++ */
++unsigned long unmap_vmas(struct mmu_gather **tlbp,
++ struct vm_area_struct *vma, unsigned long start_addr,
++ unsigned long end_addr, unsigned long *nr_accounted,
++ struct zap_details *details)
++{
++ long zap_work = ZAP_BLOCK_SIZE;
++ unsigned long tlb_start = 0; /* For tlb_finish_mmu */
++ int tlb_start_valid = 0;
++ unsigned long start = start_addr;
++ spinlock_t *i_mmap_lock = details? details->i_mmap_lock: NULL;
++ int fullmm = (*tlbp)->fullmm;
++ struct mm_struct *mm = vma->vm_mm;
++
++ mmu_notifier_invalidate_range_start(mm, start_addr, end_addr);
++ for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next) {
++ unsigned long end;
++
++ start = max(vma->vm_start, start_addr);
++ if (start >= vma->vm_end)
++ continue;
++ end = min(vma->vm_end, end_addr);
++ if (end <= vma->vm_start)
++ continue;
++
++ if (vma->vm_flags & VM_ACCOUNT)
++ *nr_accounted += (end - start) >> PAGE_SHIFT;
++
++ while (start != end) {
++ if (!tlb_start_valid) {
++ tlb_start = start;
++ tlb_start_valid = 1;
++ }
++
++ if (unlikely(is_vm_hugetlb_page(vma))) {
++ /*
++ * It is undesirable to test vma->vm_file as it
++ * should be non-null for valid hugetlb area.
++ * However, vm_file will be NULL in the error
++ * cleanup path of do_mmap_pgoff. When
++ * hugetlbfs ->mmap method fails,
++ * do_mmap_pgoff() nullifies vma->vm_file
++ * before calling this function to clean up.
++ * Since no pte has actually been setup, it is
++ * safe to do nothing in this case.
++ */
++ if (vma->vm_file) {
++ unmap_hugepage_range(vma, start, end, NULL);
++ zap_work -= (end - start) /
++ pages_per_huge_page(hstate_vma(vma));
++ }
++
++ start = end;
++ } else
++ start = unmap_page_range(*tlbp, vma,
++ start, end, &zap_work, details);
++
++ if (zap_work > 0) {
++ BUG_ON(start != end);
++ break;
++ }
++
++ tlb_finish_mmu(*tlbp, tlb_start, start);
++
++ if (need_resched() ||
++ (i_mmap_lock && spin_needbreak(i_mmap_lock))) {
++ if (i_mmap_lock) {
++ *tlbp = NULL;
++ goto out;
++ }
++ cond_resched();
++ }
++
++ *tlbp = tlb_gather_mmu(vma->vm_mm, fullmm);
++ tlb_start_valid = 0;
++ zap_work = ZAP_BLOCK_SIZE;
++ }
++ }
++out:
++ mmu_notifier_invalidate_range_end(mm, start_addr, end_addr);
++ return start; /* which is now the end (or restart) address */
++}
++
++/**
++ * zap_page_range - remove user pages in a given range
++ * @vma: vm_area_struct holding the applicable pages
++ * @address: starting address of pages to zap
++ * @size: number of bytes to zap
++ * @details: details of nonlinear truncation or shared cache invalidation
++ */
++unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address,
++ unsigned long size, struct zap_details *details)
++{
++ struct mm_struct *mm = vma->vm_mm;
++ struct mmu_gather *tlb;
++ unsigned long end = address + size;
++ unsigned long nr_accounted = 0;
++
++ lru_add_drain();
++ tlb = tlb_gather_mmu(mm, 0);
++ update_hiwater_rss(mm);
++ end = unmap_vmas(&tlb, vma, address, end, &nr_accounted, details);
++ if (tlb)
++ tlb_finish_mmu(tlb, address, end);
++ return end;
++}
++
++/**
++ * zap_vma_ptes - remove ptes mapping the vma
++ * @vma: vm_area_struct holding ptes to be zapped
++ * @address: starting address of pages to zap
++ * @size: number of bytes to zap
++ *
++ * This function only unmaps ptes assigned to VM_PFNMAP vmas.
++ *
++ * The entire address range must be fully contained within the vma.
++ *
++ * Returns 0 if successful.
++ */
++int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
++ unsigned long size)
++{
++ if (address < vma->vm_start || address + size > vma->vm_end ||
++ !(vma->vm_flags & VM_PFNMAP))
++ return -1;
++ zap_page_range(vma, address, size, NULL);
++ return 0;
++}
++EXPORT_SYMBOL_GPL(zap_vma_ptes);
++
++/*
++ * Do a quick page-table lookup for a single page.
++ */
++struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
++ unsigned int flags)
++{
++ pgd_t *pgd;
++ pud_t *pud;
++ pmd_t *pmd;
++ pte_t *ptep, pte;
++ spinlock_t *ptl;
++ struct page *page;
++ struct mm_struct *mm = vma->vm_mm;
++
++ page = follow_huge_addr(mm, address, flags & FOLL_WRITE);
++ if (!IS_ERR(page)) {
++ BUG_ON(flags & FOLL_GET);
++ goto out;
++ }
++
++ page = NULL;
++ pgd = pgd_offset(mm, address);
++ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
++ goto no_page_table;
++
++ pud = pud_offset(pgd, address);
++ if (pud_none(*pud))
++ goto no_page_table;
++ if (pud_huge(*pud)) {
++ BUG_ON(flags & FOLL_GET);
++ page = follow_huge_pud(mm, address, pud, flags & FOLL_WRITE);
++ goto out;
++ }
++ if (unlikely(pud_bad(*pud)))
++ goto no_page_table;
++
++ pmd = pmd_offset(pud, address);
++ if (pmd_none(*pmd))
++ goto no_page_table;
++ if (pmd_huge(*pmd)) {
++ BUG_ON(flags & FOLL_GET);
++ page = follow_huge_pmd(mm, address, pmd, flags & FOLL_WRITE);
++ goto out;
++ }
++ if (unlikely(pmd_bad(*pmd)))
++ goto no_page_table;
++
++ ptep = pte_offset_map_lock(mm, pmd, address, &ptl);
++
++ pte = *ptep;
++ if (!pte_present(pte))
++ goto no_page;
++ if ((flags & FOLL_WRITE) && !pte_write(pte))
++ goto unlock;
++ page = vm_normal_page(vma, address, pte);
++ if (unlikely(!page))
++ goto bad_page;
++
++ if (flags & FOLL_GET)
++ get_page(page);
++ if (flags & FOLL_TOUCH) {
++ if ((flags & FOLL_WRITE) &&
++ !pte_dirty(pte) && !PageDirty(page))
++ set_page_dirty(page);
++ mark_page_accessed(page);
++ }
++unlock:
++ pte_unmap_unlock(ptep, ptl);
++out:
++ return page;
++
++bad_page:
++ pte_unmap_unlock(ptep, ptl);
++ return ERR_PTR(-EFAULT);
++
++no_page:
++ pte_unmap_unlock(ptep, ptl);
++ if (!pte_none(pte))
++ return page;
++ /* Fall through to ZERO_PAGE handling */
++no_page_table:
++ /*
++ * When core dumping an enormous anonymous area that nobody
++ * has touched so far, we don't want to allocate page tables.
++ */
++ if (flags & FOLL_ANON) {
++ page = ZERO_PAGE(0);
++ if (flags & FOLL_GET)
++ get_page(page);
++ BUG_ON(flags & FOLL_WRITE);
++ }
++ return page;
++}
++
++/* Can we do the FOLL_ANON optimization? */
++static inline int use_zero_page(struct vm_area_struct *vma)
++{
++ /*
++ * We don't want to optimize FOLL_ANON for make_pages_present()
++ * when it tries to page in a VM_LOCKED region. As to VM_SHARED,
++ * we want to get the page from the page tables to make sure
++ * that we serialize and update with any other user of that
++ * mapping.
++ */
++ if (vma->vm_flags & (VM_LOCKED | VM_SHARED))
++ return 0;
++ /*
++ * And if we have a fault routine, it's not an anonymous region.
++ */
++ return !vma->vm_ops || !vma->vm_ops->fault;
++}
++
++int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
++ unsigned long start, int len, int write, int force,
++ struct page **pages, struct vm_area_struct **vmas)
++{
++ int i;
++ unsigned int vm_flags;
++
++ if (len <= 0)
++ return 0;
++ /*
++ * Require read or write permissions.
++ * If 'force' is set, we only require the "MAY" flags.
++ */
++ vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
++ vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
++ i = 0;
++
++ do {
++ struct vm_area_struct *vma;
++ unsigned int foll_flags;
++
++ vma = find_extend_vma(mm, start);
++ if (!vma && in_gate_area(tsk, start)) {
++ unsigned long pg = start & PAGE_MASK;
++ struct vm_area_struct *gate_vma = get_gate_vma(tsk);
++ pgd_t *pgd;
++ pud_t *pud;
++ pmd_t *pmd;
++ pte_t *pte;
++ if (write) /* user gate pages are read-only */
++ return i ? : -EFAULT;
++ if (pg > TASK_SIZE)
++ pgd = pgd_offset_k(pg);
++ else
++ pgd = pgd_offset_gate(mm, pg);
++ BUG_ON(pgd_none(*pgd));
++ pud = pud_offset(pgd, pg);
++ BUG_ON(pud_none(*pud));
++ pmd = pmd_offset(pud, pg);
++ if (pmd_none(*pmd))
++ return i ? : -EFAULT;
++ pte = pte_offset_map(pmd, pg);
++ if (pte_none(*pte)) {
++ pte_unmap(pte);
++ return i ? : -EFAULT;
++ }
++ if (pages) {
++ struct page *page = vm_normal_page(gate_vma, start, *pte);
++ pages[i] = page;
++ if (page)
++ get_page(page);
++ }
++ pte_unmap(pte);
++ if (vmas)
++ vmas[i] = gate_vma;
++ i++;
++ start += PAGE_SIZE;
++ len--;
++ continue;
++ }
++
++ if (!vma || (vma->vm_flags & (VM_IO | VM_PFNMAP))
++ || !(vm_flags & vma->vm_flags))
++ return i ? : -EFAULT;
++
++ if (is_vm_hugetlb_page(vma)) {
++ i = follow_hugetlb_page(mm, vma, pages, vmas,
++ &start, &len, i, write);
++ continue;
++ }
++
++ foll_flags = FOLL_TOUCH;
++ if (pages)
++ foll_flags |= FOLL_GET;
++ if (!write && use_zero_page(vma))
++ foll_flags |= FOLL_ANON;
++
++ do {
++ struct page *page;
++
++ /*
++ * If tsk is ooming, cut off its access to large memory
++ * allocations. It has a pending SIGKILL, but it can't
++ * be processed until returning to user space.
++ */
++ if (unlikely(test_tsk_thread_flag(tsk, TIF_MEMDIE)))
++ return i ? i : -ENOMEM;
++
++ if (write)
++ foll_flags |= FOLL_WRITE;
++
++ cond_resched();
++ while (!(page = follow_page(vma, start, foll_flags))) {
++ int ret;
++ ret = handle_mm_fault(mm, vma, start,
++ foll_flags & FOLL_WRITE);
++ if (ret & VM_FAULT_ERROR) {
++ if (ret & VM_FAULT_OOM)
++ return i ? i : -ENOMEM;
++ else if (ret & VM_FAULT_SIGBUS)
++ return i ? i : -EFAULT;
++ BUG();
++ }
++ if (ret & VM_FAULT_MAJOR)
++ tsk->maj_flt++;
++ else
++ tsk->min_flt++;
++
++ /*
++ * The VM_FAULT_WRITE bit tells us that
++ * do_wp_page has broken COW when necessary,
++ * even if maybe_mkwrite decided not to set
++ * pte_write. We can thus safely do subsequent
++ * page lookups as if they were reads.
++ */
++ if (ret & VM_FAULT_WRITE)
++ foll_flags &= ~FOLL_WRITE;
++
++ cond_resched();
++ }
++ if (IS_ERR(page))
++ return i ? i : PTR_ERR(page);
++ if (pages) {
++ pages[i] = page;
++
++ flush_anon_page(vma, page, start);
++ flush_dcache_page(page);
++ }
++ if (vmas)
++ vmas[i] = vma;
++ i++;
++ start += PAGE_SIZE;
++ len--;
++ } while (len && start < vma->vm_end);
++ } while (len);
++ return i;
++}
++EXPORT_SYMBOL(get_user_pages);
++
++pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
++ spinlock_t **ptl)
++{
++ pgd_t * pgd = pgd_offset(mm, addr);
++ pud_t * pud = pud_alloc(mm, pgd, addr);
++ if (pud) {
++ pmd_t * pmd = pmd_alloc(mm, pud, addr);
++ if (pmd)
++ return pte_alloc_map_lock(mm, pmd, addr, ptl);
++ }
++ return NULL;
++}
++
++/*
++ * This is the old fallback for page remapping.
++ *
++ * For historical reasons, it only allows reserved pages. Only
++ * old drivers should use this, and they needed to mark their
++ * pages reserved for the old functions anyway.
++ */
++static int insert_page(struct vm_area_struct *vma, unsigned long addr,
++ struct page *page, pgprot_t prot)
++{
++ struct mm_struct *mm = vma->vm_mm;
++ int retval;
++ pte_t *pte;
++ spinlock_t *ptl;
++
++ retval = mem_cgroup_charge(page, mm, GFP_KERNEL);
++ if (retval)
++ goto out;
++
++ retval = -EINVAL;
++ if (PageAnon(page))
++ goto out_uncharge;
++ retval = -ENOMEM;
++ flush_dcache_page(page);
++ pte = get_locked_pte(mm, addr, &ptl);
++ if (!pte)
++ goto out_uncharge;
++ retval = -EBUSY;
++ if (!pte_none(*pte))
++ goto out_unlock;
++
++ /* Ok, finally just insert the thing.. */
++ get_page(page);
++ inc_mm_counter(mm, file_rss);
++ page_add_file_rmap(page);
++ set_pte_at(mm, addr, pte, mk_pte(page, prot));
++
++ retval = 0;
++ pte_unmap_unlock(pte, ptl);
++ return retval;
++out_unlock:
++ pte_unmap_unlock(pte, ptl);
++out_uncharge:
++ mem_cgroup_uncharge_page(page);
++out:
++ return retval;
++}
++
++/**
++ * vm_insert_page - insert single page into user vma
++ * @vma: user vma to map to
++ * @addr: target user address of this page
++ * @page: source kernel page
++ *
++ * This allows drivers to insert individual pages they've allocated
++ * into a user vma.
++ *
++ * The page has to be a nice clean _individual_ kernel allocation.
++ * If you allocate a compound page, you need to have marked it as
++ * such (__GFP_COMP), or manually just split the page up yourself
++ * (see split_page()).
++ *
++ * NOTE! Traditionally this was done with "remap_pfn_range()" which
++ * took an arbitrary page protection parameter. This doesn't allow
++ * that. Your vma protection will have to be set up correctly, which
++ * means that if you want a shared writable mapping, you'd better
++ * ask for a shared writable mapping!
++ *
++ * The page does not need to be reserved.
++ */
++int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
++ struct page *page)
++{
++ if (addr < vma->vm_start || addr >= vma->vm_end)
++ return -EFAULT;
++ if (!page_count(page))
++ return -EINVAL;
++ vma->vm_flags |= VM_INSERTPAGE;
++ return insert_page(vma, addr, page, vma->vm_page_prot);
++}
++EXPORT_SYMBOL(vm_insert_page);
++
++static int insert_pfn(struct vm_area_struct *vma, unsigned long addr,
++ unsigned long pfn, pgprot_t prot)
++{
++ struct mm_struct *mm = vma->vm_mm;
++ int retval;
++ pte_t *pte, entry;
++ spinlock_t *ptl;
++
++ retval = -ENOMEM;
++ pte = get_locked_pte(mm, addr, &ptl);
++ if (!pte)
++ goto out;
++ retval = -EBUSY;
++ if (!pte_none(*pte))
++ goto out_unlock;
++
++ /* Ok, finally just insert the thing.. */
++ entry = pte_mkspecial(pfn_pte(pfn, prot));
++ set_pte_at(mm, addr, pte, entry);
++ update_mmu_cache(vma, addr, entry); /* XXX: why not for insert_page? */
++
++ retval = 0;
++out_unlock:
++ pte_unmap_unlock(pte, ptl);
++out:
++ return retval;
++}
++
++/**
++ * vm_insert_pfn - insert single pfn into user vma
++ * @vma: user vma to map to
++ * @addr: target user address of this page
++ * @pfn: source kernel pfn
++ *
++ * Similar to vm_inert_page, this allows drivers to insert individual pages
++ * they've allocated into a user vma. Same comments apply.
++ *
++ * This function should only be called from a vm_ops->fault handler, and
++ * in that case the handler should return NULL.
++ *
++ * vma cannot be a COW mapping.
++ *
++ * As this is called only for pages that do not currently exist, we
++ * do not need to flush old virtual caches or the TLB.
++ */
++int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
++ unsigned long pfn)
++{
++ /*
++ * Technically, architectures with pte_special can avoid all these
++ * restrictions (same for remap_pfn_range). However we would like
++ * consistency in testing and feature parity among all, so we should
++ * try to keep these invariants in place for everybody.
++ */
++ BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
++ BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
++ (VM_PFNMAP|VM_MIXEDMAP));
++ BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
++ BUG_ON((vma->vm_flags & VM_MIXEDMAP) && pfn_valid(pfn));
++
++ if (addr < vma->vm_start || addr >= vma->vm_end)
++ return -EFAULT;
++ return insert_pfn(vma, addr, pfn, vma->vm_page_prot);
++}
++EXPORT_SYMBOL(vm_insert_pfn);
++
++int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
++ unsigned long pfn)
++{
++ BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));
++
++ if (addr < vma->vm_start || addr >= vma->vm_end)
++ return -EFAULT;
++
++ /*
++ * If we don't have pte special, then we have to use the pfn_valid()
++ * based VM_MIXEDMAP scheme (see vm_normal_page), and thus we *must*
++ * refcount the page if pfn_valid is true (hence insert_page rather
++ * than insert_pfn).
++ */
++ if (!HAVE_PTE_SPECIAL && pfn_valid(pfn)) {
++ struct page *page;
++
++ page = pfn_to_page(pfn);
++ return insert_page(vma, addr, page, vma->vm_page_prot);
++ }
++ return insert_pfn(vma, addr, pfn, vma->vm_page_prot);
++}
++EXPORT_SYMBOL(vm_insert_mixed);
++
++/*
++ * maps a range of physical memory into the requested pages. the old
++ * mappings are removed. any references to nonexistent pages results
++ * in null mappings (currently treated as "copy-on-access")
++ */
++static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd,
++ unsigned long addr, unsigned long end,
++ unsigned long pfn, pgprot_t prot)
++{
++ pte_t *pte;
++ spinlock_t *ptl;
++
++ pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
++ if (!pte)
++ return -ENOMEM;
++ arch_enter_lazy_mmu_mode();
++ do {
++ BUG_ON(!pte_none(*pte));
++ set_pte_at(mm, addr, pte, pte_mkspecial(pfn_pte(pfn, prot)));
++ pfn++;
++ } while (pte++, addr += PAGE_SIZE, addr != end);
++ arch_leave_lazy_mmu_mode();
++ pte_unmap_unlock(pte - 1, ptl);
++ return 0;
++}
++
++static inline int remap_pmd_range(struct mm_struct *mm, pud_t *pud,
++ unsigned long addr, unsigned long end,
++ unsigned long pfn, pgprot_t prot)
++{
++ pmd_t *pmd;
++ unsigned long next;
++
++ pfn -= addr >> PAGE_SHIFT;
++ pmd = pmd_alloc(mm, pud, addr);
++ if (!pmd)
++ return -ENOMEM;
++ do {
++ next = pmd_addr_end(addr, end);
++ if (remap_pte_range(mm, pmd, addr, next,
++ pfn + (addr >> PAGE_SHIFT), prot))
++ return -ENOMEM;
++ } while (pmd++, addr = next, addr != end);
++ return 0;
++}
++
++static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd,
++ unsigned long addr, unsigned long end,
++ unsigned long pfn, pgprot_t prot)
++{
++ pud_t *pud;
++ unsigned long next;
++
++ pfn -= addr >> PAGE_SHIFT;
++ pud = pud_alloc(mm, pgd, addr);
++ if (!pud)
++ return -ENOMEM;
++ do {
++ next = pud_addr_end(addr, end);
++ if (remap_pmd_range(mm, pud, addr, next,
++ pfn + (addr >> PAGE_SHIFT), prot))
++ return -ENOMEM;
++ } while (pud++, addr = next, addr != end);
++ return 0;
++}
++
++/**
++ * remap_pfn_range - remap kernel memory to userspace
++ * @vma: user vma to map to
++ * @addr: target user address to start at
++ * @pfn: physical address of kernel memory
++ * @size: size of map area
++ * @prot: page protection flags for this mapping
++ *
++ * Note: this is only safe if the mm semaphore is held when called.
++ */
++int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
++ unsigned long pfn, unsigned long size, pgprot_t prot)
++{
++ pgd_t *pgd;
++ unsigned long next;
++ unsigned long end = addr + PAGE_ALIGN(size);
++ struct mm_struct *mm = vma->vm_mm;
++ int err;
++
++ /*
++ * Physically remapped pages are special. Tell the
++ * rest of the world about it:
++ * VM_IO tells people not to look at these pages
++ * (accesses can have side effects).
++ * VM_RESERVED is specified all over the place, because
++ * in 2.4 it kept swapout's vma scan off this vma; but
++ * in 2.6 the LRU scan won't even find its pages, so this
++ * flag means no more than count its pages in reserved_vm,
++ * and omit it from core dump, even when VM_IO turned off.
++ * VM_PFNMAP tells the core MM that the base pages are just
++ * raw PFN mappings, and do not have a "struct page" associated
++ * with them.
++ *
++ * There's a horrible special case to handle copy-on-write
++ * behaviour that some programs depend on. We mark the "original"
++ * un-COW'ed pages by matching them up with "vma->vm_pgoff".
++ */
++ if (is_cow_mapping(vma->vm_flags)) {
++ if (addr != vma->vm_start || end != vma->vm_end)
++ return -EINVAL;
++ vma->vm_pgoff = pfn;
++ }
++
++ vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
++
++ BUG_ON(addr >= end);
++ pfn -= addr >> PAGE_SHIFT;
++ pgd = pgd_offset(mm, addr);
++ flush_cache_range(vma, addr, end);
++ do {
++ next = pgd_addr_end(addr, end);
++ err = remap_pud_range(mm, pgd, addr, next,
++ pfn + (addr >> PAGE_SHIFT), prot);
++ if (err)
++ break;
++ } while (pgd++, addr = next, addr != end);
++ return err;
++}
++EXPORT_SYMBOL(remap_pfn_range);
++
++static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
++ unsigned long addr, unsigned long end,
++ pte_fn_t fn, void *data)
++{
++ pte_t *pte;
++ int err;
++ pgtable_t token;
++ spinlock_t *uninitialized_var(ptl);
++
++ pte = (mm == &init_mm) ?
++ pte_alloc_kernel(pmd, addr) :
++ pte_alloc_map_lock(mm, pmd, addr, &ptl);
++ if (!pte)
++ return -ENOMEM;
++
++ BUG_ON(pmd_huge(*pmd));
++
++ token = pmd_pgtable(*pmd);
++
++ do {
++ err = fn(pte, token, addr, data);
++ if (err)
++ break;
++ } while (pte++, addr += PAGE_SIZE, addr != end);
++
++ if (mm != &init_mm)
++ pte_unmap_unlock(pte-1, ptl);
++ return err;
++}
++
++static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud,
++ unsigned long addr, unsigned long end,
++ pte_fn_t fn, void *data)
++{
++ pmd_t *pmd;
++ unsigned long next;
++ int err;
++
++ BUG_ON(pud_huge(*pud));
++
++ pmd = pmd_alloc(mm, pud, addr);
++ if (!pmd)
++ return -ENOMEM;
++ do {
++ next = pmd_addr_end(addr, end);
++ err = apply_to_pte_range(mm, pmd, addr, next, fn, data);
++ if (err)
++ break;
++ } while (pmd++, addr = next, addr != end);
++ return err;
++}
++
++static int apply_to_pud_range(struct mm_struct *mm, pgd_t *pgd,
++ unsigned long addr, unsigned long end,
++ pte_fn_t fn, void *data)
++{
++ pud_t *pud;
++ unsigned long next;
++ int err;
++
++ pud = pud_alloc(mm, pgd, addr);
++ if (!pud)
++ return -ENOMEM;
++ do {
++ next = pud_addr_end(addr, end);
++ err = apply_to_pmd_range(mm, pud, addr, next, fn, data);
++ if (err)
++ break;
++ } while (pud++, addr = next, addr != end);
++ return err;
++}
++
++/*
++ * Scan a region of virtual memory, filling in page tables as necessary
++ * and calling a provided function on each leaf page table.
++ */
++int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
++ unsigned long size, pte_fn_t fn, void *data)
++{
++ pgd_t *pgd;
++ unsigned long next;
++ unsigned long start = addr, end = addr + size;
++ int err;
++
++ BUG_ON(addr >= end);
++ mmu_notifier_invalidate_range_start(mm, start, end);
++ pgd = pgd_offset(mm, addr);
++ do {
++ next = pgd_addr_end(addr, end);
++ err = apply_to_pud_range(mm, pgd, addr, next, fn, data);
++ if (err)
++ break;
++ } while (pgd++, addr = next, addr != end);
++ mmu_notifier_invalidate_range_end(mm, start, end);
++ return err;
++}
++EXPORT_SYMBOL_GPL(apply_to_page_range);
++
++/*
++ * handle_pte_fault chooses page fault handler according to an entry
++ * which was read non-atomically. Before making any commitment, on
++ * those architectures or configurations (e.g. i386 with PAE) which
++ * might give a mix of unmatched parts, do_swap_page and do_file_page
++ * must check under lock before unmapping the pte and proceeding
++ * (but do_wp_page is only called after already making such a check;
++ * and do_anonymous_page and do_no_page can safely check later on).
++ */
++static inline int pte_unmap_same(struct mm_struct *mm, pmd_t *pmd,
++ pte_t *page_table, pte_t orig_pte)
++{
++ int same = 1;
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
++ if (sizeof(pte_t) > sizeof(unsigned long)) {
++ spinlock_t *ptl = pte_lockptr(mm, pmd);
++ spin_lock(ptl);
++ same = pte_same(*page_table, orig_pte);
++ spin_unlock(ptl);
++ }
++#endif
++ pte_unmap(page_table);
++ return same;
++}
++
++/*
++ * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
++ * servicing faults for write access. In the normal case, do always want
++ * pte_mkwrite. But get_user_pages can cause write faults for mappings
++ * that do not have writing enabled, when used by access_process_vm.
++ */
++static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
++{
++ if (likely(vma->vm_flags & VM_WRITE))
++ pte = pte_mkwrite(pte);
++ return pte;
++}
++
++static inline void cow_user_page(struct page *dst, struct page *src, unsigned long va, struct vm_area_struct *vma)
++{
++ /*
++ * If the source page was a PFN mapping, we don't have
++ * a "struct page" for it. We do a best-effort copy by
++ * just copying from the original user address. If that
++ * fails, we just zero-fill it. Live with it.
++ */
++ if (unlikely(!src)) {
++ void *kaddr = kmap_atomic(dst, KM_USER0);
++ void __user *uaddr = (void __user *)(va & PAGE_MASK);
++
++ /*
++ * This really shouldn't fail, because the page is there
++ * in the page tables. But it might just be unreadable,
++ * in which case we just give up and fill the result with
++ * zeroes.
++ */
++ if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
++ memset(kaddr, 0, PAGE_SIZE);
++ kunmap_atomic(kaddr, KM_USER0);
++ flush_dcache_page(dst);
++ } else
++ copy_user_highpage(dst, src, va, vma);
++}
++
++/*
++ * This routine handles present pages, when users try to write
++ * to a shared page. It is done by copying the page to a new address
++ * and decrementing the shared-page counter for the old page.
++ *
++ * Note that this routine assumes that the protection checks have been
++ * done by the caller (the low-level page fault routine in most cases).
++ * Thus we can safely just mark it writable once we've done any necessary
++ * COW.
++ *
++ * We also mark the page dirty at this point even though the page will
++ * change only once the write actually happens. This avoids a few races,
++ * and potentially makes it more efficient.
++ *
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), with pte both mapped and locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pte_t *page_table, pmd_t *pmd,
++ spinlock_t *ptl, pte_t orig_pte)
++{
++ struct page *old_page, *new_page;
++ pte_t entry;
++ int reuse = 0, ret = 0;
++ int page_mkwrite = 0;
++ struct page *dirty_page = NULL;
++
++ old_page = vm_normal_page(vma, address, orig_pte);
++ if (!old_page) {
++ /*
++ * VM_MIXEDMAP !pfn_valid() case
++ *
++ * We should not cow pages in a shared writeable mapping.
++ * Just mark the pages writable as we can't do any dirty
++ * accounting on raw pfn maps.
++ */
++ if ((vma->vm_flags & (VM_WRITE|VM_SHARED)) ==
++ (VM_WRITE|VM_SHARED))
++ goto reuse;
++ goto gotten;
++ }
++
++ /*
++ * Take out anonymous pages first, anonymous shared vmas are
++ * not dirty accountable.
++ */
++ if (PageAnon(old_page)) {
++ if (trylock_page(old_page)) {
++ reuse = can_share_swap_page(old_page);
++ unlock_page(old_page);
++ }
++ } else if (unlikely((vma->vm_flags & (VM_WRITE|VM_SHARED)) ==
++ (VM_WRITE|VM_SHARED))) {
++ /*
++ * Only catch write-faults on shared writable pages,
++ * read-only shared pages can get COWed by
++ * get_user_pages(.write=1, .force=1).
++ */
++ if (vma->vm_ops && vma->vm_ops->page_mkwrite) {
++ /*
++ * Notify the address space that the page is about to
++ * become writable so that it can prohibit this or wait
++ * for the page to get into an appropriate state.
++ *
++ * We do this without the lock held, so that it can
++ * sleep if it needs to.
++ */
++ page_cache_get(old_page);
++ pte_unmap_unlock(page_table, ptl);
++
++ if (vma->vm_ops->page_mkwrite(vma, old_page) < 0)
++ goto unwritable_page;
++
++ /*
++ * Since we dropped the lock we need to revalidate
++ * the PTE as someone else may have changed it. If
++ * they did, we just return, as we can count on the
++ * MMU to tell us if they didn't also make it writable.
++ */
++ page_table = pte_offset_map_lock(mm, pmd, address,
++ &ptl);
++ page_cache_release(old_page);
++ if (!pte_same(*page_table, orig_pte))
++ goto unlock;
++
++ page_mkwrite = 1;
++ }
++ dirty_page = old_page;
++ get_page(dirty_page);
++ reuse = 1;
++ }
++
++ if (reuse) {
++reuse:
++ flush_cache_page(vma, address, pte_pfn(orig_pte));
++ entry = pte_mkyoung(orig_pte);
++ entry = maybe_mkwrite(pte_mkdirty(entry), vma);
++ if (ptep_set_access_flags(vma, address, page_table, entry,1))
++ update_mmu_cache(vma, address, entry);
++ ret |= VM_FAULT_WRITE;
++ goto unlock;
++ }
++
++ /*
++ * Ok, we need to copy. Oh, well..
++ */
++ page_cache_get(old_page);
++gotten:
++ pte_unmap_unlock(page_table, ptl);
++
++ if (unlikely(anon_vma_prepare(vma)))
++ goto oom;
++ VM_BUG_ON(old_page == ZERO_PAGE(0));
++ new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
++ if (!new_page)
++ goto oom;
++ cow_user_page(new_page, old_page, address, vma);
++ __SetPageUptodate(new_page);
++
++ if (mem_cgroup_charge(new_page, mm, GFP_KERNEL))
++ goto oom_free_new;
++
++ /*
++ * Re-check the pte - we dropped the lock
++ */
++ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
++ if (likely(pte_same(*page_table, orig_pte))) {
++ if (old_page) {
++ if (!PageAnon(old_page)) {
++ dec_mm_counter(mm, file_rss);
++ inc_mm_counter(mm, anon_rss);
++ }
++ } else
++ inc_mm_counter(mm, anon_rss);
++ flush_cache_page(vma, address, pte_pfn(orig_pte));
++ entry = mk_pte(new_page, vma->vm_page_prot);
++ entry = maybe_mkwrite(pte_mkdirty(entry), vma);
++ /*
++ * Clear the pte entry and flush it first, before updating the
++ * pte with the new entry. This will avoid a race condition
++ * seen in the presence of one thread doing SMC and another
++ * thread doing COW.
++ */
++ ptep_clear_flush_notify(vma, address, page_table);
++ set_pte_at(mm, address, page_table, entry);
++ update_mmu_cache(vma, address, entry);
++ lru_cache_add_active(new_page);
++ page_add_new_anon_rmap(new_page, vma, address);
++
++ if (old_page) {
++ /*
++ * Only after switching the pte to the new page may
++ * we remove the mapcount here. Otherwise another
++ * process may come and find the rmap count decremented
++ * before the pte is switched to the new page, and
++ * "reuse" the old page writing into it while our pte
++ * here still points into it and can be read by other
++ * threads.
++ *
++ * The critical issue is to order this
++ * page_remove_rmap with the ptp_clear_flush above.
++ * Those stores are ordered by (if nothing else,)
++ * the barrier present in the atomic_add_negative
++ * in page_remove_rmap.
++ *
++ * Then the TLB flush in ptep_clear_flush ensures that
++ * no process can access the old page before the
++ * decremented mapcount is visible. And the old page
++ * cannot be reused until after the decremented
++ * mapcount is visible. So transitively, TLBs to
++ * old page will be flushed before it can be reused.
++ */
++ page_remove_rmap(old_page, vma);
++ }
++
++ /* Free the old page.. */
++ new_page = old_page;
++ ret |= VM_FAULT_WRITE;
++ } else
++ mem_cgroup_uncharge_page(new_page);
++
++ if (new_page)
++ page_cache_release(new_page);
++ if (old_page)
++ page_cache_release(old_page);
++unlock:
++ pte_unmap_unlock(page_table, ptl);
++ if (dirty_page) {
++ if (vma->vm_file)
++ file_update_time(vma->vm_file);
++
++ /*
++ * Yes, Virginia, this is actually required to prevent a race
++ * with clear_page_dirty_for_io() from clearing the page dirty
++ * bit after it clear all dirty ptes, but before a racing
++ * do_wp_page installs a dirty pte.
++ *
++ * do_no_page is protected similarly.
++ */
++ wait_on_page_locked(dirty_page);
++ set_page_dirty_balance(dirty_page, page_mkwrite);
++ put_page(dirty_page);
++ }
++ return ret;
++oom_free_new:
++ page_cache_release(new_page);
++oom:
++ if (old_page)
++ page_cache_release(old_page);
++ return VM_FAULT_OOM;
++
++unwritable_page:
++ page_cache_release(old_page);
++ return VM_FAULT_SIGBUS;
++}
++
++/*
++ * Helper functions for unmap_mapping_range().
++ *
++ * __ Notes on dropping i_mmap_lock to reduce latency while unmapping __
++ *
++ * We have to restart searching the prio_tree whenever we drop the lock,
++ * since the iterator is only valid while the lock is held, and anyway
++ * a later vma might be split and reinserted earlier while lock dropped.
++ *
++ * The list of nonlinear vmas could be handled more efficiently, using
++ * a placeholder, but handle it in the same way until a need is shown.
++ * It is important to search the prio_tree before nonlinear list: a vma
++ * may become nonlinear and be shifted from prio_tree to nonlinear list
++ * while the lock is dropped; but never shifted from list to prio_tree.
++ *
++ * In order to make forward progress despite restarting the search,
++ * vm_truncate_count is used to mark a vma as now dealt with, so we can
++ * quickly skip it next time around. Since the prio_tree search only
++ * shows us those vmas affected by unmapping the range in question, we
++ * can't efficiently keep all vmas in step with mapping->truncate_count:
++ * so instead reset them all whenever it wraps back to 0 (then go to 1).
++ * mapping->truncate_count and vma->vm_truncate_count are protected by
++ * i_mmap_lock.
++ *
++ * In order to make forward progress despite repeatedly restarting some
++ * large vma, note the restart_addr from unmap_vmas when it breaks out:
++ * and restart from that address when we reach that vma again. It might
++ * have been split or merged, shrunk or extended, but never shifted: so
++ * restart_addr remains valid so long as it remains in the vma's range.
++ * unmap_mapping_range forces truncate_count to leap over page-aligned
++ * values so we can save vma's restart_addr in its truncate_count field.
++ */
++#define is_restart_addr(truncate_count) (!((truncate_count) & ~PAGE_MASK))
++
++static void reset_vma_truncate_counts(struct address_space *mapping)
++{
++ struct vm_area_struct *vma;
++ struct prio_tree_iter iter;
++
++ vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX)
++ vma->vm_truncate_count = 0;
++ list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list)
++ vma->vm_truncate_count = 0;
++}
++
++static int unmap_mapping_range_vma(struct vm_area_struct *vma,
++ unsigned long start_addr, unsigned long end_addr,
++ struct zap_details *details)
++{
++ unsigned long restart_addr;
++ int need_break;
++
++ /*
++ * files that support invalidating or truncating portions of the
++ * file from under mmaped areas must have their ->fault function
++ * return a locked page (and set VM_FAULT_LOCKED in the return).
++ * This provides synchronisation against concurrent unmapping here.
++ */
++
++again:
++ restart_addr = vma->vm_truncate_count;
++ if (is_restart_addr(restart_addr) && start_addr < restart_addr) {
++ start_addr = restart_addr;
++ if (start_addr >= end_addr) {
++ /* Top of vma has been split off since last time */
++ vma->vm_truncate_count = details->truncate_count;
++ return 0;
++ }
++ }
++
++ restart_addr = zap_page_range(vma, start_addr,
++ end_addr - start_addr, details);
++ need_break = need_resched() || spin_needbreak(details->i_mmap_lock);
++
++ if (restart_addr >= end_addr) {
++ /* We have now completed this vma: mark it so */
++ vma->vm_truncate_count = details->truncate_count;
++ if (!need_break)
++ return 0;
++ } else {
++ /* Note restart_addr in vma's truncate_count field */
++ vma->vm_truncate_count = restart_addr;
++ if (!need_break)
++ goto again;
++ }
++
++ spin_unlock(details->i_mmap_lock);
++ cond_resched();
++ spin_lock(details->i_mmap_lock);
++ return -EINTR;
++}
++
++static inline void unmap_mapping_range_tree(struct prio_tree_root *root,
++ struct zap_details *details)
++{
++ struct vm_area_struct *vma;
++ struct prio_tree_iter iter;
++ pgoff_t vba, vea, zba, zea;
++
++restart:
++ vma_prio_tree_foreach(vma, &iter, root,
++ details->first_index, details->last_index) {
++ /* Skip quickly over those we have already dealt with */
++ if (vma->vm_truncate_count == details->truncate_count)
++ continue;
++
++ vba = vma->vm_pgoff;
++ vea = vba + ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) - 1;
++ /* Assume for now that PAGE_CACHE_SHIFT == PAGE_SHIFT */
++ zba = details->first_index;
++ if (zba < vba)
++ zba = vba;
++ zea = details->last_index;
++ if (zea > vea)
++ zea = vea;
++
++ if (unmap_mapping_range_vma(vma,
++ ((zba - vba) << PAGE_SHIFT) + vma->vm_start,
++ ((zea - vba + 1) << PAGE_SHIFT) + vma->vm_start,
++ details) < 0)
++ goto restart;
++ }
++}
++
++static inline void unmap_mapping_range_list(struct list_head *head,
++ struct zap_details *details)
++{
++ struct vm_area_struct *vma;
++
++ /*
++ * In nonlinear VMAs there is no correspondence between virtual address
++ * offset and file offset. So we must perform an exhaustive search
++ * across *all* the pages in each nonlinear VMA, not just the pages
++ * whose virtual address lies outside the file truncation point.
++ */
++restart:
++ list_for_each_entry(vma, head, shared.vm_set.list) {
++ /* Skip quickly over those we have already dealt with */
++ if (vma->vm_truncate_count == details->truncate_count)
++ continue;
++ details->nonlinear_vma = vma;
++ if (unmap_mapping_range_vma(vma, vma->vm_start,
++ vma->vm_end, details) < 0)
++ goto restart;
++ }
++}
++
++/**
++ * unmap_mapping_range - unmap the portion of all mmaps in the specified address_space corresponding to the specified page range in the underlying file.
++ * @mapping: the address space containing mmaps to be unmapped.
++ * @holebegin: byte in first page to unmap, relative to the start of
++ * the underlying file. This will be rounded down to a PAGE_SIZE
++ * boundary. Note that this is different from vmtruncate(), which
++ * must keep the partial page. In contrast, we must get rid of
++ * partial pages.
++ * @holelen: size of prospective hole in bytes. This will be rounded
++ * up to a PAGE_SIZE boundary. A holelen of zero truncates to the
++ * end of the file.
++ * @even_cows: 1 when truncating a file, unmap even private COWed pages;
++ * but 0 when invalidating pagecache, don't throw away private data.
++ */
++void unmap_mapping_range(struct address_space *mapping,
++ loff_t const holebegin, loff_t const holelen, int even_cows)
++{
++ struct zap_details details;
++ pgoff_t hba = holebegin >> PAGE_SHIFT;
++ pgoff_t hlen = (holelen + PAGE_SIZE - 1) >> PAGE_SHIFT;
++
++ /* Check for overflow. */
++ if (sizeof(holelen) > sizeof(hlen)) {
++ long long holeend =
++ (holebegin + holelen + PAGE_SIZE - 1) >> PAGE_SHIFT;
++ if (holeend & ~(long long)ULONG_MAX)
++ hlen = ULONG_MAX - hba + 1;
++ }
++
++ details.check_mapping = even_cows? NULL: mapping;
++ details.nonlinear_vma = NULL;
++ details.first_index = hba;
++ details.last_index = hba + hlen - 1;
++ if (details.last_index < details.first_index)
++ details.last_index = ULONG_MAX;
++ details.i_mmap_lock = &mapping->i_mmap_lock;
++
++ spin_lock(&mapping->i_mmap_lock);
++
++ /* Protect against endless unmapping loops */
++ mapping->truncate_count++;
++ if (unlikely(is_restart_addr(mapping->truncate_count))) {
++ if (mapping->truncate_count == 0)
++ reset_vma_truncate_counts(mapping);
++ mapping->truncate_count++;
++ }
++ details.truncate_count = mapping->truncate_count;
++
++ if (unlikely(!prio_tree_empty(&mapping->i_mmap)))
++ unmap_mapping_range_tree(&mapping->i_mmap, &details);
++ if (unlikely(!list_empty(&mapping->i_mmap_nonlinear)))
++ unmap_mapping_range_list(&mapping->i_mmap_nonlinear, &details);
++ spin_unlock(&mapping->i_mmap_lock);
++}
++EXPORT_SYMBOL(unmap_mapping_range);
++
++/**
++ * vmtruncate - unmap mappings "freed" by truncate() syscall
++ * @inode: inode of the file used
++ * @offset: file offset to start truncating
++ *
++ * NOTE! We have to be ready to update the memory sharing
++ * between the file and the memory map for a potential last
++ * incomplete page. Ugly, but necessary.
++ */
++int vmtruncate(struct inode * inode, loff_t offset)
++{
++ if (inode->i_size < offset) {
++ unsigned long limit;
++
++ limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
++ if (limit != RLIM_INFINITY && offset > limit)
++ goto out_sig;
++ if (offset > inode->i_sb->s_maxbytes)
++ goto out_big;
++ i_size_write(inode, offset);
++ } else {
++ struct address_space *mapping = inode->i_mapping;
++
++ /*
++ * truncation of in-use swapfiles is disallowed - it would
++ * cause subsequent swapout to scribble on the now-freed
++ * blocks.
++ */
++ if (IS_SWAPFILE(inode))
++ return -ETXTBSY;
++ i_size_write(inode, offset);
++
++ /*
++ * unmap_mapping_range is called twice, first simply for
++ * efficiency so that truncate_inode_pages does fewer
++ * single-page unmaps. However after this first call, and
++ * before truncate_inode_pages finishes, it is possible for
++ * private pages to be COWed, which remain after
++ * truncate_inode_pages finishes, hence the second
++ * unmap_mapping_range call must be made for correctness.
++ */
++ unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
++ truncate_inode_pages(mapping, offset);
++ unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
++ }
++
++ if (inode->i_op && inode->i_op->truncate)
++ inode->i_op->truncate(inode);
++ return 0;
++
++out_sig:
++ send_sig(SIGXFSZ, current, 0);
++out_big:
++ return -EFBIG;
++}
++EXPORT_SYMBOL(vmtruncate);
++
++int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
++{
++ struct address_space *mapping = inode->i_mapping;
++
++ /*
++ * If the underlying filesystem is not going to provide
++ * a way to truncate a range of blocks (punch a hole) -
++ * we should return failure right now.
++ */
++ if (!inode->i_op || !inode->i_op->truncate_range)
++ return -ENOSYS;
++
++ mutex_lock(&inode->i_mutex);
++ down_write(&inode->i_alloc_sem);
++ unmap_mapping_range(mapping, offset, (end - offset), 1);
++ truncate_inode_pages_range(mapping, offset, end);
++ unmap_mapping_range(mapping, offset, (end - offset), 1);
++ inode->i_op->truncate_range(inode, offset, end);
++ up_write(&inode->i_alloc_sem);
++ mutex_unlock(&inode->i_mutex);
++
++ return 0;
++}
++
++/*
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), and pte mapped but not yet locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pte_t *page_table, pmd_t *pmd,
++ int write_access, pte_t orig_pte)
++{
++ spinlock_t *ptl;
++ struct page *page;
++ swp_entry_t entry;
++ pte_t pte;
++ int ret = 0;
++
++ if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
++ goto out;
++
++ entry = pte_to_swp_entry(orig_pte);
++ if (is_migration_entry(entry)) {
++ migration_entry_wait(mm, pmd, address);
++ goto out;
++ }
++ delayacct_set_flag(DELAYACCT_PF_SWAPIN);
++ page = lookup_swap_cache(entry);
++ if (!page) {
++ grab_swap_token(); /* Contend for token _before_ read-in */
++ page = swapin_readahead(entry,
++ GFP_HIGHUSER_MOVABLE, vma, address);
++ if (!page) {
++ /*
++ * Back out if somebody else faulted in this pte
++ * while we released the pte lock.
++ */
++ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
++ if (likely(pte_same(*page_table, orig_pte)))
++ ret = VM_FAULT_OOM;
++ delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
++ goto unlock;
++ }
++
++ /* Had to read the page from swap area: Major fault */
++ ret = VM_FAULT_MAJOR;
++ count_vm_event(PGMAJFAULT);
++ }
++
++ if (mem_cgroup_charge(page, mm, GFP_KERNEL)) {
++ delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
++ ret = VM_FAULT_OOM;
++ goto out;
++ }
++
++ if (!vx_rss_avail(mm, 1)) {
++ ret = VM_FAULT_OOM;
++ goto out;
++ }
++
++ mark_page_accessed(page);
++ lock_page(page);
++ delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
++
++ /*
++ * Back out if somebody else already faulted in this pte.
++ */
++ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
++ if (unlikely(!pte_same(*page_table, orig_pte)))
++ goto out_nomap;
++
++ if (unlikely(!PageUptodate(page))) {
++ ret = VM_FAULT_SIGBUS;
++ goto out_nomap;
++ }
++
++ /* The page isn't present yet, go ahead with the fault. */
++
++ inc_mm_counter(mm, anon_rss);
++ pte = mk_pte(page, vma->vm_page_prot);
++ if (write_access && can_share_swap_page(page)) {
++ pte = maybe_mkwrite(pte_mkdirty(pte), vma);
++ write_access = 0;
++ }
++
++ flush_icache_page(vma, page);
++ set_pte_at(mm, address, page_table, pte);
++ page_add_anon_rmap(page, vma, address);
++
++ swap_free(entry);
++ if (vm_swap_full())
++ remove_exclusive_swap_page(page);
++ unlock_page(page);
++
++ if (write_access) {
++ ret |= do_wp_page(mm, vma, address, page_table, pmd, ptl, pte);
++ if (ret & VM_FAULT_ERROR)
++ ret &= VM_FAULT_ERROR;
++ goto out;
++ }
++
++ /* No need to invalidate - it was non-present before */
++ update_mmu_cache(vma, address, pte);
++unlock:
++ pte_unmap_unlock(page_table, ptl);
++out:
++ return ret;
++out_nomap:
++ mem_cgroup_uncharge_page(page);
++ pte_unmap_unlock(page_table, ptl);
++ unlock_page(page);
++ page_cache_release(page);
++ return ret;
++}
++
++/*
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), and pte mapped but not yet locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pte_t *page_table, pmd_t *pmd,
++ int write_access)
++{
++ struct page *page;
++ spinlock_t *ptl;
++ pte_t entry;
++
++ /* Allocate our own private page. */
++ pte_unmap(page_table);
++
++ if (!vx_rss_avail(mm, 1))
++ goto oom;
++ if (unlikely(anon_vma_prepare(vma)))
++ goto oom;
++ page = alloc_zeroed_user_highpage_movable(vma, address);
++ if (!page)
++ goto oom;
++ __SetPageUptodate(page);
++
++ if (mem_cgroup_charge(page, mm, GFP_KERNEL))
++ goto oom_free_page;
++
++ entry = mk_pte(page, vma->vm_page_prot);
++ entry = maybe_mkwrite(pte_mkdirty(entry), vma);
++
++ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
++ if (!pte_none(*page_table))
++ goto release;
++ inc_mm_counter(mm, anon_rss);
++ lru_cache_add_active(page);
++ page_add_new_anon_rmap(page, vma, address);
++ set_pte_at(mm, address, page_table, entry);
++
++ /* No need to invalidate - it was non-present before */
++ update_mmu_cache(vma, address, entry);
++unlock:
++ pte_unmap_unlock(page_table, ptl);
++ return 0;
++release:
++ mem_cgroup_uncharge_page(page);
++ page_cache_release(page);
++ goto unlock;
++oom_free_page:
++ page_cache_release(page);
++oom:
++ return VM_FAULT_OOM;
++}
++
++/*
++ * __do_fault() tries to create a new page mapping. It aggressively
++ * tries to share with existing pages, but makes a separate copy if
++ * the FAULT_FLAG_WRITE is set in the flags parameter in order to avoid
++ * the next page fault.
++ *
++ * As this is called only for pages that do not currently exist, we
++ * do not need to flush old virtual caches or the TLB.
++ *
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), and pte neither mapped nor locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pmd_t *pmd,
++ pgoff_t pgoff, unsigned int flags, pte_t orig_pte)
++{
++ pte_t *page_table;
++ spinlock_t *ptl;
++ struct page *page;
++ pte_t entry;
++ int anon = 0;
++ struct page *dirty_page = NULL;
++ struct vm_fault vmf;
++ int ret;
++ int page_mkwrite = 0;
++
++ vmf.virtual_address = (void __user *)(address & PAGE_MASK);
++ vmf.pgoff = pgoff;
++ vmf.flags = flags;
++ vmf.page = NULL;
++
++ ret = vma->vm_ops->fault(vma, &vmf);
++ if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
++ return ret;
++
++ /*
++ * For consistency in subsequent calls, make the faulted page always
++ * locked.
++ */
++ if (unlikely(!(ret & VM_FAULT_LOCKED)))
++ lock_page(vmf.page);
++ else
++ VM_BUG_ON(!PageLocked(vmf.page));
++
++ /*
++ * Should we do an early C-O-W break?
++ */
++ page = vmf.page;
++ if (flags & FAULT_FLAG_WRITE) {
++ if (!(vma->vm_flags & VM_SHARED)) {
++ anon = 1;
++ if (unlikely(anon_vma_prepare(vma))) {
++ ret = VM_FAULT_OOM;
++ goto out;
++ }
++ page = alloc_page_vma(GFP_HIGHUSER_MOVABLE,
++ vma, address);
++ if (!page) {
++ ret = VM_FAULT_OOM;
++ goto out;
++ }
++ copy_user_highpage(page, vmf.page, address, vma);
++ __SetPageUptodate(page);
++ } else {
++ /*
++ * If the page will be shareable, see if the backing
++ * address space wants to know that the page is about
++ * to become writable
++ */
++ if (vma->vm_ops->page_mkwrite) {
++ unlock_page(page);
++ if (vma->vm_ops->page_mkwrite(vma, page) < 0) {
++ ret = VM_FAULT_SIGBUS;
++ anon = 1; /* no anon but release vmf.page */
++ goto out_unlocked;
++ }
++ lock_page(page);
++ /*
++ * XXX: this is not quite right (racy vs
++ * invalidate) to unlock and relock the page
++ * like this, however a better fix requires
++ * reworking page_mkwrite locking API, which
++ * is better done later.
++ */
++ if (!page->mapping) {
++ ret = 0;
++ anon = 1; /* no anon but release vmf.page */
++ goto out;
++ }
++ page_mkwrite = 1;
++ }
++ }
++
++ }
++
++ if (mem_cgroup_charge(page, mm, GFP_KERNEL)) {
++ ret = VM_FAULT_OOM;
++ goto out;
++ }
++
++ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
++
++ /*
++ * This silly early PAGE_DIRTY setting removes a race
++ * due to the bad i386 page protection. But it's valid
++ * for other architectures too.
++ *
++ * Note that if write_access is true, we either now have
++ * an exclusive copy of the page, or this is a shared mapping,
++ * so we can make it writable and dirty to avoid having to
++ * handle that later.
++ */
++ /* Only go through if we didn't race with anybody else... */
++ if (likely(pte_same(*page_table, orig_pte))) {
++ flush_icache_page(vma, page);
++ entry = mk_pte(page, vma->vm_page_prot);
++ if (flags & FAULT_FLAG_WRITE)
++ entry = maybe_mkwrite(pte_mkdirty(entry), vma);
++ set_pte_at(mm, address, page_table, entry);
++ if (anon) {
++ inc_mm_counter(mm, anon_rss);
++ lru_cache_add_active(page);
++ page_add_new_anon_rmap(page, vma, address);
++ } else {
++ inc_mm_counter(mm, file_rss);
++ page_add_file_rmap(page);
++ if (flags & FAULT_FLAG_WRITE) {
++ dirty_page = page;
++ get_page(dirty_page);
++ }
++ }
++
++ /* no need to invalidate: a not-present page won't be cached */
++ update_mmu_cache(vma, address, entry);
++ } else {
++ mem_cgroup_uncharge_page(page);
++ if (anon)
++ page_cache_release(page);
++ else
++ anon = 1; /* no anon but release faulted_page */
++ }
++
++ pte_unmap_unlock(page_table, ptl);
++
++out:
++ unlock_page(vmf.page);
++out_unlocked:
++ if (anon)
++ page_cache_release(vmf.page);
++ else if (dirty_page) {
++ if (vma->vm_file)
++ file_update_time(vma->vm_file);
++
++ set_page_dirty_balance(dirty_page, page_mkwrite);
++ put_page(dirty_page);
++ }
++
++ return ret;
++}
++
++static int do_linear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pte_t *page_table, pmd_t *pmd,
++ int write_access, pte_t orig_pte)
++{
++ pgoff_t pgoff = (((address & PAGE_MASK)
++ - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
++ unsigned int flags = (write_access ? FAULT_FLAG_WRITE : 0);
++
++ pte_unmap(page_table);
++ return __do_fault(mm, vma, address, pmd, pgoff, flags, orig_pte);
++}
++
++/*
++ * Fault of a previously existing named mapping. Repopulate the pte
++ * from the encoded file_pte if possible. This enables swappable
++ * nonlinear vmas.
++ *
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), and pte mapped but not yet locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static int do_nonlinear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, pte_t *page_table, pmd_t *pmd,
++ int write_access, pte_t orig_pte)
++{
++ unsigned int flags = FAULT_FLAG_NONLINEAR |
++ (write_access ? FAULT_FLAG_WRITE : 0);
++ pgoff_t pgoff;
++
++ if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
++ return 0;
++
++ if (unlikely(!(vma->vm_flags & VM_NONLINEAR) ||
++ !(vma->vm_flags & VM_CAN_NONLINEAR))) {
++ /*
++ * Page table corrupted: show pte and kill process.
++ */
++ print_bad_pte(vma, orig_pte, address);
++ return VM_FAULT_OOM;
++ }
++
++ pgoff = pte_to_pgoff(orig_pte);
++ return __do_fault(mm, vma, address, pmd, pgoff, flags, orig_pte);
++}
++
++/*
++ * These routines also need to handle stuff like marking pages dirty
++ * and/or accessed for architectures that don't do it in hardware (most
++ * RISC architectures). The early dirtying is also good on the i386.
++ *
++ * There is also a hook called "update_mmu_cache()" that architectures
++ * with external mmu caches can use to update those (ie the Sparc or
++ * PowerPC hashed page tables that act as extended TLBs).
++ *
++ * We enter with non-exclusive mmap_sem (to exclude vma changes,
++ * but allow concurrent faults), and pte mapped but not yet locked.
++ * We return with mmap_sem still held, but pte unmapped and unlocked.
++ */
++static inline int handle_pte_fault(struct mm_struct *mm,
++ struct vm_area_struct *vma, unsigned long address,
++ pte_t *pte, pmd_t *pmd, int write_access)
++{
++ pte_t entry;
++ spinlock_t *ptl;
++ int ret = 0, type = VXPT_UNKNOWN;
++
++ entry = *pte;
++ if (!pte_present(entry)) {
++ if (pte_none(entry)) {
++ if (vma->vm_ops) {
++ if (likely(vma->vm_ops->fault))
++ return do_linear_fault(mm, vma, address,
++ pte, pmd, write_access, entry);
++ }
++ return do_anonymous_page(mm, vma, address,
++ pte, pmd, write_access);
++ }
++ if (pte_file(entry))
++ return do_nonlinear_fault(mm, vma, address,
++ pte, pmd, write_access, entry);
++ return do_swap_page(mm, vma, address,
++ pte, pmd, write_access, entry);
++ }
++
++ ptl = pte_lockptr(mm, pmd);
++ spin_lock(ptl);
++ if (unlikely(!pte_same(*pte, entry)))
++ goto unlock;
++ if (write_access) {
++ if (!pte_write(entry)) {
++ ret = do_wp_page(mm, vma, address,
++ pte, pmd, ptl, entry);
++ type = VXPT_WRITE;
++ goto out;
++ }
++ entry = pte_mkdirty(entry);
++ }
++ entry = pte_mkyoung(entry);
++ if (ptep_set_access_flags(vma, address, pte, entry, write_access)) {
++ update_mmu_cache(vma, address, entry);
++ } else {
++ /*
++ * This is needed only for protection faults but the arch code
++ * is not yet telling us if this is a protection fault or not.
++ * This still avoids useless tlb flushes for .text page faults
++ * with threads.
++ */
++ if (write_access)
++ flush_tlb_page(vma, address);
++ }
++unlock:
++ pte_unmap_unlock(pte, ptl);
++ ret = 0;
++out:
++ vx_page_fault(mm, vma, type, ret);
++ return ret;
++}
++
++/*
++ * By the time we get here, we already hold the mm semaphore
++ */
++int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
++ unsigned long address, int write_access)
++{
++ pgd_t *pgd;
++ pud_t *pud;
++ pmd_t *pmd;
++ pte_t *pte;
++
++ __set_current_state(TASK_RUNNING);
++
++ count_vm_event(PGFAULT);
++
++ if (unlikely(is_vm_hugetlb_page(vma)))
++ return hugetlb_fault(mm, vma, address, write_access);
++
++ pgd = pgd_offset(mm, address);
++ pud = pud_alloc(mm, pgd, address);
++ if (!pud)
++ return VM_FAULT_OOM;
++ pmd = pmd_alloc(mm, pud, address);
++ if (!pmd)
++ return VM_FAULT_OOM;
++ pte = pte_alloc_map(mm, pmd, address);
++ if (!pte)
++ return VM_FAULT_OOM;
++
++ return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
++}
++
++#ifndef __PAGETABLE_PUD_FOLDED
++/*
++ * Allocate page upper directory.
++ * We've already handled the fast-path in-line.
++ */
++int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
++{
++ pud_t *new = pud_alloc_one(mm, address);
++ if (!new)
++ return -ENOMEM;
++
++ smp_wmb(); /* See comment in __pte_alloc */
++
++ spin_lock(&mm->page_table_lock);
++ if (pgd_present(*pgd)) /* Another has populated it */
++ pud_free(mm, new);
++ else
++ pgd_populate(mm, pgd, new);
++ spin_unlock(&mm->page_table_lock);
++ return 0;
++}
++#endif /* __PAGETABLE_PUD_FOLDED */
++
++#ifndef __PAGETABLE_PMD_FOLDED
++/*
++ * Allocate page middle directory.
++ * We've already handled the fast-path in-line.
++ */
++int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
++{
++ pmd_t *new = pmd_alloc_one(mm, address);
++ if (!new)
++ return -ENOMEM;
++
++ smp_wmb(); /* See comment in __pte_alloc */
++
++ spin_lock(&mm->page_table_lock);
++#ifndef __ARCH_HAS_4LEVEL_HACK
++ if (pud_present(*pud)) /* Another has populated it */
++ pmd_free(mm, new);
++ else
++ pud_populate(mm, pud, new);
++#else
++ if (pgd_present(*pud)) /* Another has populated it */
++ pmd_free(mm, new);
++ else
++ pgd_populate(mm, pud, new);
++#endif /* __ARCH_HAS_4LEVEL_HACK */
++ spin_unlock(&mm->page_table_lock);
++ return 0;
++}
++#endif /* __PAGETABLE_PMD_FOLDED */
++
++int make_pages_present(unsigned long addr, unsigned long end)
++{
++ int ret, len, write;
++ struct vm_area_struct * vma;
++
++ vma = find_vma(current->mm, addr);
++ if (!vma)
++ return -ENOMEM;
++ write = (vma->vm_flags & VM_WRITE) != 0;
++ BUG_ON(addr >= end);
++ BUG_ON(end > vma->vm_end);
++ len = DIV_ROUND_UP(end, PAGE_SIZE) - addr/PAGE_SIZE;
++ ret = get_user_pages(current, current->mm, addr,
++ len, write, 0, NULL, NULL);
++ if (ret < 0) {
++ /*
++ SUS require strange return value to mlock
++ - invalid addr generate to ENOMEM.
++ - out of memory should generate EAGAIN.
++ */
++ if (ret == -EFAULT)
++ ret = -ENOMEM;
++ else if (ret == -ENOMEM)
++ ret = -EAGAIN;
++ return ret;
++ }
++ return ret == len ? 0 : -ENOMEM;
++}
++
++#if !defined(__HAVE_ARCH_GATE_AREA)
++
++#if defined(AT_SYSINFO_EHDR)
++static struct vm_area_struct gate_vma;
++
++static int __init gate_vma_init(void)
++{
++ gate_vma.vm_mm = NULL;
++ gate_vma.vm_start = FIXADDR_USER_START;
++ gate_vma.vm_end = FIXADDR_USER_END;
++ gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
++ gate_vma.vm_page_prot = __P101;
++ /*
++ * Make sure the vDSO gets into every core dump.
++ * Dumping its contents makes post-mortem fully interpretable later
++ * without matching up the same kernel and hardware config to see
++ * what PC values meant.
++ */
++ gate_vma.vm_flags |= VM_ALWAYSDUMP;
++ return 0;
++}
++__initcall(gate_vma_init);
++#endif
++
++struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
++{
++#ifdef AT_SYSINFO_EHDR
++ return &gate_vma;
++#else
++ return NULL;
++#endif
++}
++
++int in_gate_area_no_task(unsigned long addr)
++{
++#ifdef AT_SYSINFO_EHDR
++ if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
++ return 1;
++#endif
++ return 0;
++}
++
++#endif /* __HAVE_ARCH_GATE_AREA */
++
++#ifdef CONFIG_HAVE_IOREMAP_PROT
++static resource_size_t follow_phys(struct vm_area_struct *vma,
++ unsigned long address, unsigned int flags,
++ unsigned long *prot)
++{
++ pgd_t *pgd;
++ pud_t *pud;
++ pmd_t *pmd;
++ pte_t *ptep, pte;
++ spinlock_t *ptl;
++ resource_size_t phys_addr = 0;
++ struct mm_struct *mm = vma->vm_mm;
++
++ VM_BUG_ON(!(vma->vm_flags & (VM_IO | VM_PFNMAP)));
++
++ pgd = pgd_offset(mm, address);
++ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
++ goto no_page_table;
++
++ pud = pud_offset(pgd, address);
++ if (pud_none(*pud) || unlikely(pud_bad(*pud)))
++ goto no_page_table;
++
++ pmd = pmd_offset(pud, address);
++ if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
++ goto no_page_table;
++
++ /* We cannot handle huge page PFN maps. Luckily they don't exist. */
++ if (pmd_huge(*pmd))
++ goto no_page_table;
++
++ ptep = pte_offset_map_lock(mm, pmd, address, &ptl);
++ if (!ptep)
++ goto out;
++
++ pte = *ptep;
++ if (!pte_present(pte))
++ goto unlock;
++ if ((flags & FOLL_WRITE) && !pte_write(pte))
++ goto unlock;
++ phys_addr = pte_pfn(pte);
++ phys_addr <<= PAGE_SHIFT; /* Shift here to avoid overflow on PAE */
++
++ *prot = pgprot_val(pte_pgprot(pte));
++
++unlock:
++ pte_unmap_unlock(ptep, ptl);
++out:
++ return phys_addr;
++no_page_table:
++ return 0;
++}
++
++int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
++ void *buf, int len, int write)
++{
++ resource_size_t phys_addr;
++ unsigned long prot = 0;
++ void *maddr;
++ int offset = addr & (PAGE_SIZE-1);
++
++ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
++ return -EINVAL;
++
++ phys_addr = follow_phys(vma, addr, write, &prot);
++
++ if (!phys_addr)
++ return -EINVAL;
++
++ maddr = ioremap_prot(phys_addr, PAGE_SIZE, prot);
++ if (write)
++ memcpy_toio(maddr + offset, buf, len);
++ else
++ memcpy_fromio(buf, maddr + offset, len);
++ iounmap(maddr);
++
++ return len;
++}
++#endif
++
++/*
++ * Access another process' address space.
++ * Source/target buffer must be kernel space,
++ * Do not walk the page table directly, use get_user_pages
++ */
++int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
++{
++ struct mm_struct *mm;
++ struct vm_area_struct *vma;
++ void *old_buf = buf;
++
++ mm = get_task_mm(tsk);
++ if (!mm)
++ return 0;
++
++ down_read(&mm->mmap_sem);
++ /* ignore errors, just check how much was successfully transferred */
++ while (len) {
++ int bytes, ret, offset;
++ void *maddr;
++ struct page *page = NULL;
++
++ ret = get_user_pages(tsk, mm, addr, 1,
++ write, 1, &page, &vma);
++ if (ret <= 0) {
++ /*
++ * Check if this is a VM_IO | VM_PFNMAP VMA, which
++ * we can access using slightly different code.
++ */
++#ifdef CONFIG_HAVE_IOREMAP_PROT
++ vma = find_vma(mm, addr);
++ if (!vma)
++ break;
++ if (vma->vm_ops && vma->vm_ops->access)
++ ret = vma->vm_ops->access(vma, addr, buf,
++ len, write);
++ if (ret <= 0)
++#endif
++ break;
++ bytes = ret;
++ } else {
++ bytes = len;
++ offset = addr & (PAGE_SIZE-1);
++ if (bytes > PAGE_SIZE-offset)
++ bytes = PAGE_SIZE-offset;
++
++ maddr = kmap(page);
++ if (write) {
++ copy_to_user_page(vma, page, addr,
++ maddr + offset, buf, bytes);
++ set_page_dirty_lock(page);
++ } else {
++ copy_from_user_page(vma, page, addr,
++ buf, maddr + offset, bytes);
++ }
++ kunmap(page);
++ page_cache_release(page);
++ }
++ len -= bytes;
++ buf += bytes;
++ addr += bytes;
++ }
++ up_read(&mm->mmap_sem);
++ mmput(mm);
++
++ return buf - old_buf;
++}
++
++/*
++ * Print the name of a VMA.
++ */
++void print_vma_addr(char *prefix, unsigned long ip)
++{
++ struct mm_struct *mm = current->mm;
++ struct vm_area_struct *vma;
++
++ /*
++ * Do not print if we are in atomic
++ * contexts (in exception stacks, etc.):
++ */
++ if (preempt_count())
++ return;
++
++ down_read(&mm->mmap_sem);
++ vma = find_vma(mm, ip);
++ if (vma && vma->vm_file) {
++ struct file *f = vma->vm_file;
++ char *buf = (char *)__get_free_page(GFP_KERNEL);
++ if (buf) {
++ char *p, *s;
++
++ p = d_path(&f->f_path, buf, PAGE_SIZE);
++ if (IS_ERR(p))
++ p = "?";
++ s = strrchr(p, '/');
++ if (s)
++ p = s+1;
++ printk("%s%s[%lx+%lx]", prefix, p,
++ vma->vm_start,
++ vma->vm_end - vma->vm_start);
++ free_page((unsigned long)buf);
++ }
++ }
++ up_read(¤t->mm->mmap_sem);
++}
+diff -Nurb linux-2.6.27-590/mm/slab.c linux-2.6.27-591/mm/slab.c
+--- linux-2.6.27-590/mm/slab.c 2010-02-01 19:42:07.000000000 -0500
++++ linux-2.6.27-591/mm/slab.c 2010-02-01 19:43:07.000000000 -0500
@@ -110,6 +110,7 @@
#include <linux/fault-inject.h>
#include <linux/rtmutex.h>
#include <linux/debugobjects.h>
#include <asm/cacheflush.h>
-@@ -248,6 +249,14 @@ struct slab_rcu {
+@@ -248,6 +249,14 @@
void *addr;
};
/*
* struct array_cache
*
-@@ -3469,6 +3478,19 @@ __cache_alloc(struct kmem_cache *cachep,
+@@ -3469,6 +3478,19 @@
local_irq_restore(save_flags);
objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller);
prefetchw(objp);
if (unlikely((flags & __GFP_ZERO) && objp))
memset(objp, 0, obj_size(cachep));
-@@ -3578,12 +3600,26 @@ free_done:
+@@ -3578,12 +3600,26 @@
* Release an obj back to its cache. If the obj has a constructed state, it must
* be in this state _before_ it is released. Called with disabled ints.
*/
vx_slab_free(cachep);
/*
-@@ -3714,6 +3750,7 @@ static __always_inline void *__do_kmallo
+@@ -3714,6 +3750,7 @@
void *caller)
{
struct kmem_cache *cachep;
/* If you want to save a few bytes .text space: replace
* __ with kmem_.
-@@ -3741,10 +3778,17 @@ void *__kmalloc_track_caller(size_t size
+@@ -3741,10 +3778,17 @@
EXPORT_SYMBOL(__kmalloc_track_caller);
#else
EXPORT_SYMBOL(__kmalloc);
#endif
-@@ -3764,7 +3808,7 @@ void kmem_cache_free(struct kmem_cache *
+@@ -3764,7 +3808,7 @@
debug_check_no_locks_freed(objp, obj_size(cachep));
if (!(cachep->flags & SLAB_DEBUG_OBJECTS))
debug_check_no_obj_freed(objp, obj_size(cachep));
local_irq_restore(flags);
}
EXPORT_SYMBOL(kmem_cache_free);
-@@ -3790,7 +3834,7 @@ void kfree(const void *objp)
+@@ -3790,7 +3834,7 @@
c = virt_to_cache(objp);
debug_check_no_locks_freed(objp, obj_size(c));
debug_check_no_obj_freed(objp, obj_size(c));