* Andi Kleen.
*
* CPU hotplug support - ashok.raj@intel.com
- * $Id: process.c,v 1.38 2002/01/15 10:08:03 ak Exp $
*/
/*
#include <linux/ptrace.h>
#include <linux/utsname.h>
#include <linux/random.h>
-#include <linux/kprobes.h>
#include <linux/notifier.h>
+#include <linux/kprobes.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
asmlinkage extern void ret_from_fork(void);
-unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
+unsigned long kernel_thread_flags =
+ CLONE_VM | CLONE_UNTRACED | CLONE_KTHREAD;
unsigned long boot_option_idle_override = 0;
EXPORT_SYMBOL(boot_option_idle_override);
* Powermanagement idle function, if any..
*/
void (*pm_idle)(void);
+EXPORT_SYMBOL(pm_idle);
static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
-static struct notifier_block *idle_notifier;
-static DEFINE_SPINLOCK(idle_notifier_lock);
+static ATOMIC_NOTIFIER_HEAD(idle_notifier);
void idle_notifier_register(struct notifier_block *n)
{
- unsigned long flags;
- spin_lock_irqsave(&idle_notifier_lock, flags);
- notifier_chain_register(&idle_notifier, n);
- spin_unlock_irqrestore(&idle_notifier_lock, flags);
+ atomic_notifier_chain_register(&idle_notifier, n);
}
EXPORT_SYMBOL_GPL(idle_notifier_register);
void idle_notifier_unregister(struct notifier_block *n)
{
- unsigned long flags;
- spin_lock_irqsave(&idle_notifier_lock, flags);
- notifier_chain_unregister(&idle_notifier, n);
- spin_unlock_irqrestore(&idle_notifier_lock, flags);
+ atomic_notifier_chain_unregister(&idle_notifier, n);
}
EXPORT_SYMBOL(idle_notifier_unregister);
-enum idle_state { CPU_IDLE, CPU_NOT_IDLE };
-static DEFINE_PER_CPU(enum idle_state, idle_state) = CPU_NOT_IDLE;
-
void enter_idle(void)
{
- __get_cpu_var(idle_state) = CPU_IDLE;
- notifier_call_chain(&idle_notifier, IDLE_START, NULL);
+ write_pda(isidle, 1);
+ atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
}
static void __exit_idle(void)
{
- __get_cpu_var(idle_state) = CPU_NOT_IDLE;
- notifier_call_chain(&idle_notifier, IDLE_END, NULL);
+ if (test_and_clear_bit_pda(0, isidle) == 0)
+ return;
+ atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
}
/* Called from interrupts to signify idle end */
void exit_idle(void)
{
- if (current->pid | read_pda(irqcount))
+ /* idle loop has pid 0 */
+ if (current->pid)
return;
__exit_idle();
}
* We use this if we don't have any better
* idle routine..
*/
-void default_idle(void)
+static void default_idle(void)
{
- local_irq_enable();
-
- clear_thread_flag(TIF_POLLING_NRFLAG);
- smp_mb__after_clear_bit();
- while (!need_resched()) {
- local_irq_disable();
- if (!need_resched())
- safe_halt();
- else
- local_irq_enable();
- }
- set_thread_flag(TIF_POLLING_NRFLAG);
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we
+ * test NEED_RESCHED:
+ */
+ smp_mb();
+ local_irq_disable();
+ if (!need_resched()) {
+ /* Enables interrupts one instruction before HLT.
+ x86 special cases this so there is no race. */
+ safe_halt();
+ } else
+ local_irq_enable();
+ current_thread_info()->status |= TS_POLLING;
}
/*
static void poll_idle (void)
{
local_irq_enable();
-
- asm volatile(
- "2:"
- "testl %0,%1;"
- "rep; nop;"
- "je 2b;"
- : :
- "i" (_TIF_NEED_RESCHED),
- "m" (current_thread_info()->flags));
+ cpu_relax();
}
void cpu_idle_wait(void)
{
unsigned int cpu, this_cpu = get_cpu();
- cpumask_t map;
+ cpumask_t map, tmp = current->cpus_allowed;
set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
put_cpu();
}
cpus_and(map, map, cpu_online_map);
} while (!cpus_empty(map));
+
+ set_cpus_allowed(current, tmp);
}
EXPORT_SYMBOL_GPL(cpu_idle_wait);
*/
void cpu_idle (void)
{
- set_thread_flag(TIF_POLLING_NRFLAG);
-
+ current_thread_info()->status |= TS_POLLING;
/* endless idle loop with no priority at all */
while (1) {
while (!need_resched()) {
idle = default_idle;
if (cpu_is_offline(smp_processor_id()))
play_dead();
+ /*
+ * Idle routines should keep interrupts disabled
+ * from here on, until they go to idle.
+ * Otherwise, idle callbacks can misfire.
+ */
+ local_irq_disable();
enter_idle();
idle();
+ /* In many cases the interrupt that ended idle
+ has already called exit_idle. But some idle
+ loops can be woken up without interrupt. */
__exit_idle();
}
* We execute MONITOR against need_resched and enter optimized wait state
* through MWAIT. Whenever someone changes need_resched, we would be woken
* up from MWAIT (without an IPI).
+ *
+ * New with Core Duo processors, MWAIT can take some hints based on CPU
+ * capability.
*/
-static void mwait_idle(void)
+void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
{
- local_irq_enable();
+ if (!need_resched()) {
+ __monitor((void *)¤t_thread_info()->flags, 0, 0);
+ smp_mb();
+ if (!need_resched())
+ __mwait(eax, ecx);
+ }
+}
- while (!need_resched()) {
+/* Default MONITOR/MWAIT with no hints, used for default C1 state */
+static void mwait_idle(void)
+{
+ if (!need_resched()) {
__monitor((void *)¤t_thread_info()->flags, 0, 0);
smp_mb();
- if (need_resched())
- break;
- __mwait(0, 0);
+ if (!need_resched())
+ __sti_mwait(0, 0);
+ else
+ local_irq_enable();
+ } else {
+ local_irq_enable();
}
}
printk("\n");
print_modules();
- printk("Pid: %d, comm: %.20s %s %s %.*s\n",
- current->pid, current->comm, print_tainted(),
- system_utsname.release,
- (int)strcspn(system_utsname.version, " "),
- system_utsname.version);
+ printk("Pid: %d:#%u, comm: %.20s %s %s %.*s\n",
+ current->pid, current->xid, current->comm, print_tainted(),
+ init_utsname()->release,
+ (int)strcspn(init_utsname()->version, " "),
+ init_utsname()->version);
printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip);
printk_address(regs->rip);
- printk("\nRSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp,
+ printk("RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp,
regs->eflags);
printk("RAX: %016lx RBX: %016lx RCX: %016lx\n",
regs->rax, regs->rbx, regs->rcx);
{
printk("CPU %d:", smp_processor_id());
__show_regs(regs);
- show_trace(®s->rsp);
+ show_trace(NULL, regs, (void *)(regs + 1));
}
/*
struct task_struct *me = current;
struct thread_struct *t = &me->thread;
- /*
- * Remove function-return probe instances associated with this task
- * and put them back on the free list. Do not insert an exit probe for
- * this function, it will be disabled by kprobe_flush_task if you do.
- */
- kprobe_flush_task(me);
-
if (me->thread.io_bitmap_ptr) {
struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
kfree(t->io_bitmap_ptr);
t->io_bitmap_ptr = NULL;
+ clear_thread_flag(TIF_IO_BITMAP);
/*
* Careful, clear this in the TSS too:
*/
struct task_struct *tsk = current;
struct thread_info *t = current_thread_info();
- if (t->flags & _TIF_ABI_PENDING)
+ if (t->flags & _TIF_ABI_PENDING) {
t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32);
+ if (t->flags & _TIF_IA32)
+ current_thread_info()->status |= TS_COMPAT;
+ }
+ t->flags &= ~_TIF_DEBUG;
tsk->thread.debugreg0 = 0;
tsk->thread.debugreg1 = 0;
asm("mov %%es,%0" : "=m" (p->thread.es));
asm("mov %%ds,%0" : "=m" (p->thread.ds));
- if (unlikely(me->thread.io_bitmap_ptr != NULL)) {
+ if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!p->thread.io_bitmap_ptr) {
p->thread.io_bitmap_max = 0;
}
memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr,
IO_BITMAP_BYTES);
+ set_tsk_thread_flag(p, TIF_IO_BITMAP);
}
/*
/*
* This special macro can be used to load a debugging register
*/
-#define loaddebug(thread,r) set_debug(thread->debugreg ## r, r)
+#define loaddebug(thread,r) set_debugreg(thread->debugreg ## r, r)
+
+static inline void __switch_to_xtra(struct task_struct *prev_p,
+ struct task_struct *next_p,
+ struct tss_struct *tss)
+{
+ struct thread_struct *prev, *next;
+
+ prev = &prev_p->thread,
+ next = &next_p->thread;
+
+ if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
+ loaddebug(next, 0);
+ loaddebug(next, 1);
+ loaddebug(next, 2);
+ loaddebug(next, 3);
+ /* no 4 and 5 */
+ loaddebug(next, 6);
+ loaddebug(next, 7);
+ }
+
+ if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
+ /*
+ * Copy the relevant range of the IO bitmap.
+ * Normally this is 128 bytes or less:
+ */
+ memcpy(tss->io_bitmap, next->io_bitmap_ptr,
+ max(prev->io_bitmap_max, next->io_bitmap_max));
+ } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) {
+ /*
+ * Clear any possible leftover bits:
+ */
+ memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
+ }
+}
/*
* switch_to(x,y) should switch tasks from x to y.
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(init_tss, cpu);
+ /* we're going to use this soon, after a few expensive things */
+ if (next_p->fpu_counter>5)
+ prefetch(&next->i387.fxsave);
+
/*
* Reload esp0, LDT and the page table pointer:
*/
prev->gsindex = gsindex;
}
+ /* Must be after DS reload */
+ unlazy_fpu(prev_p);
+
/*
- * Switch the PDA context.
+ * Switch the PDA and FPU contexts.
*/
prev->userrsp = read_pda(oldrsp);
write_pda(oldrsp, next->userrsp);
write_pda(pcurrent, next_p);
- /* This must be here to ensure both math_state_restore() and
- kernel_fpu_begin() work consistently.
- And the AMD workaround requires it to be after DS reload. */
- unlazy_fpu(prev_p);
-
write_pda(kernelstack,
- task_stack_page(next_p) + THREAD_SIZE - PDA_STACKOFFSET);
-
+ (unsigned long)task_stack_page(next_p) + THREAD_SIZE - PDA_STACKOFFSET);
+#ifdef CONFIG_CC_STACKPROTECTOR
+ write_pda(stack_canary, next_p->stack_canary);
/*
- * Now maybe reload the debug registers
+ * Build time only check to make sure the stack_canary is at
+ * offset 40 in the pda; this is a gcc ABI requirement
*/
- if (unlikely(next->debugreg7)) {
- loaddebug(next, 0);
- loaddebug(next, 1);
- loaddebug(next, 2);
- loaddebug(next, 3);
- /* no 4 and 5 */
- loaddebug(next, 6);
- loaddebug(next, 7);
- }
-
+ BUILD_BUG_ON(offsetof(struct x8664_pda, stack_canary) != 40);
+#endif
- /*
- * Handle the IO bitmap
- */
- if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr)) {
- if (next->io_bitmap_ptr)
- /*
- * Copy the relevant range of the IO bitmap.
- * Normally this is 128 bytes or less:
- */
- memcpy(tss->io_bitmap, next->io_bitmap_ptr,
- max(prev->io_bitmap_max, next->io_bitmap_max));
- else {
- /*
- * Clear any possible leftover bits:
- */
- memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
- }
- }
+ /*
+ * Now maybe reload the debug registers and handle I/O bitmaps
+ */
+ if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW))
+ || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP))
+ __switch_to_xtra(prev_p, next_p, tss);
+ /* If the task has used fpu the last 5 timeslices, just do a full
+ * restore of the math state immediately to avoid the trap; the
+ * chances of needing FPU soon are obviously high now
+ */
+ if (next_p->fpu_counter>5)
+ math_state_restore();
return prev_p;
}
if (IS_ERR(filename))
return error;
error = do_execve(filename, argv, envp, ®s);
- if (error == 0) {
- task_lock(current);
- current->ptrace &= ~PT_DTRACE;
- task_unlock(current);
- }
putname(filename);
return error;
}
/* Make sure to be in 64bit mode */
clear_thread_flag(TIF_IA32);
-
- /* TBD: overwrites user setup. Should have two bits.
- But 64bit processes have always behaved this way,
- so it's not too bad. The main problem is just that
- 32bit childs are affected again. */
- current->personality &= ~READ_IMPLIES_EXEC;
}
asmlinkage long sys_fork(struct pt_regs *regs)
}
case ARCH_GET_GS: {
unsigned long base;
+ unsigned gsindex;
if (task->thread.gsindex == GS_TLS_SEL)
base = read_32bit_tls(task, GS_TLS);
- else if (doit)
- rdmsrl(MSR_KERNEL_GS_BASE, base);
+ else if (doit) {
+ asm("movl %%gs,%0" : "=r" (gsindex));
+ if (gsindex)
+ rdmsrl(MSR_KERNEL_GS_BASE, base);
+ else
+ base = task->thread.gs;
+ }
else
base = task->thread.gs;
ret = put_user(base, (unsigned long __user *)addr);
unsigned long arch_align_stack(unsigned long sp)
{
- if (randomize_va_space)
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
sp -= get_random_int() % 8192;
return sp & ~0xf;
}
git://git.onelab.eu / linux-2.6.git / blobdiff