#include <stdarg.h>
+#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <asm/ldt.h>
#include <asm/processor.h>
#include <asm/i387.h>
-#include <asm/irq.h>
#include <asm/desc.h>
+#include <asm/vm86.h>
#ifdef CONFIG_MATH_EMULATION
#include <asm/math_emu.h>
#endif
-#include <linux/irq.h>
#include <linux/err.h>
+#include <asm/tlbflush.h>
+#include <asm/cpu.h>
+
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
static int hlt_counter;
* Powermanagement idle function, if any..
*/
void (*pm_idle)(void);
+EXPORT_SYMBOL(pm_idle);
static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
void disable_hlt(void)
*/
void default_idle(void)
{
+ local_irq_enable();
+
if (!hlt_counter && boot_cpu_data.hlt_works_ok) {
- local_irq_disable();
- if (!need_resched())
- safe_halt();
- else
- 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);
} else {
- cpu_relax();
+ while (!need_resched())
+ cpu_relax();
}
}
+#ifdef CONFIG_APM_MODULE
+EXPORT_SYMBOL(default_idle);
+#endif
/*
* On SMP it's slightly faster (but much more power-consuming!)
*/
static void poll_idle (void)
{
- int oldval;
-
local_irq_enable();
- /*
- * Deal with another CPU just having chosen a thread to
- * run here:
- */
- oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
+ asm volatile(
+ "2:"
+ "testl %0, %1;"
+ "rep; nop;"
+ "je 2b;"
+ : : "i"(_TIF_NEED_RESCHED), "m" (current_thread_info()->flags));
+}
- if (!oldval) {
- set_thread_flag(TIF_POLLING_NRFLAG);
- asm volatile(
- "2:"
- "testl %0, %1;"
- "rep; nop;"
- "je 2b;"
- : : "i"(_TIF_NEED_RESCHED), "m" (current_thread_info()->flags));
+#ifdef CONFIG_HOTPLUG_CPU
+#include <asm/nmi.h>
+/* We don't actually take CPU down, just spin without interrupts. */
+static inline void play_dead(void)
+{
+ /* This must be done before dead CPU ack */
+ cpu_exit_clear();
+ wbinvd();
+ mb();
+ /* Ack it */
+ __get_cpu_var(cpu_state) = CPU_DEAD;
- clear_thread_flag(TIF_POLLING_NRFLAG);
- } else {
- set_need_resched();
- }
+ /*
+ * With physical CPU hotplug, we should halt the cpu
+ */
+ local_irq_disable();
+ while (1)
+ halt();
}
+#else
+static inline void play_dead(void)
+{
+ BUG();
+}
+#endif /* CONFIG_HOTPLUG_CPU */
/*
* The idle thread. There's no useful work to be
* low exit latency (ie sit in a loop waiting for
* somebody to say that they'd like to reschedule)
*/
-void cpu_idle (void)
+void cpu_idle(void)
{
+ int cpu = smp_processor_id();
+
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
/* endless idle loop with no priority at all */
while (1) {
while (!need_resched()) {
if (!idle)
idle = default_idle;
+ if (cpu_is_offline(cpu))
+ play_dead();
+
__get_cpu_var(irq_stat).idle_timestamp = jiffies;
idle();
}
+ preempt_enable_no_resched();
schedule();
+ preempt_disable();
}
}
{
local_irq_enable();
- if (!need_resched()) {
- set_thread_flag(TIF_POLLING_NRFLAG);
- do {
- __monitor((void *)¤t_thread_info()->flags, 0, 0);
- if (need_resched())
- break;
- __mwait(0, 0);
- } while (!need_resched());
- clear_thread_flag(TIF_POLLING_NRFLAG);
+ while (!need_resched()) {
+ __monitor((void *)¤t_thread_info()->flags, 0, 0);
+ smp_mb();
+ if (need_resched())
+ break;
+ __mwait(0, 0);
}
}
-void __init select_idle_routine(const struct cpuinfo_x86 *c)
+void __devinit select_idle_routine(const struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_MWAIT)) {
printk("monitor/mwait feature present.\n");
printk("EIP: %04x:[<%08lx>] CPU: %d\n",0xffff & regs->xcs,regs->eip, smp_processor_id());
print_symbol("EIP is at %s\n", regs->eip);
- if (regs->xcs & 3)
+ if (user_mode_vm(regs))
printk(" ESP: %04x:%08lx",0xffff & regs->xss,regs->esp);
- printk(" EFLAGS: %08lx %s (%s)\n",
- regs->eflags, print_tainted(), system_utsname.release);
+ printk(" EFLAGS: %08lx %s (%s %.*s)\n",
+ regs->eflags, print_tainted(), system_utsname.release,
+ (int)strcspn(system_utsname.version, " "),
+ system_utsname.version);
printk("EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n",
regs->eax,regs->ebx,regs->ecx,regs->edx);
printk("ESI: %08lx EDI: %08lx EBP: %08lx",
printk(" DS: %04x ES: %04x\n",
0xffff & regs->xds,0xffff & regs->xes);
- __asm__("movl %%cr0, %0": "=r" (cr0));
- __asm__("movl %%cr2, %0": "=r" (cr2));
- __asm__("movl %%cr3, %0": "=r" (cr3));
- /* This could fault if %cr4 does not exist */
- __asm__("1: movl %%cr4, %0 \n"
- "2: \n"
- ".section __ex_table,\"a\" \n"
- ".long 1b,2b \n"
- ".previous \n"
- : "=r" (cr4): "0" (0));
+ cr0 = read_cr0();
+ cr2 = read_cr2();
+ cr3 = read_cr3();
+ cr4 = read_cr4_safe();
printk("CR0: %08lx CR2: %08lx CR3: %08lx CR4: %08lx\n", cr0, cr2, cr3, cr4);
show_trace(NULL, ®s->esp);
}
/* Ok, create the new process.. */
return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL);
}
+EXPORT_SYMBOL(kernel_thread);
/*
* Free current thread data structures etc..
void release_thread(struct task_struct *dead_task)
{
- if (dead_task->mm) {
- // temporary debugging check
- if (dead_task->mm->context.size) {
- printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
- dead_task->comm,
- dead_task->mm->context.ldt,
- dead_task->mm->context.size);
- BUG();
- }
- }
-
+ BUG_ON(dead_task->mm);
release_vm86_irqs(dead_task);
}
struct task_struct *tsk;
int err;
- childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
- /*
- * The below -8 is to reserve 8 bytes on top of the ring0 stack.
- * This is necessary to guarantee that the entire "struct pt_regs"
- * is accessable even if the CPU haven't stored the SS/ESP registers
- * on the stack (interrupt gate does not save these registers
- * when switching to the same priv ring).
- * Therefore beware: accessing the xss/esp fields of the
- * "struct pt_regs" is possible, but they may contain the
- * completely wrong values.
- */
- childregs = (struct pt_regs *) ((unsigned long) childregs - 8);
+ childregs = task_pt_regs(p);
*childregs = *regs;
childregs->eax = 0;
childregs->esp = esp;
dump->u_fpvalid = dump_fpu (regs, &dump->i387);
}
+EXPORT_SYMBOL(dump_thread);
/*
* Capture the user space registers if the task is not running (in user space)
*/
int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
{
- struct pt_regs ptregs;
-
- ptregs = *(struct pt_regs *)
- ((unsigned long)tsk->thread_info+THREAD_SIZE - sizeof(ptregs));
+ struct pt_regs ptregs = *task_pt_regs(tsk);
ptregs.xcs &= 0xffff;
ptregs.xds &= 0xffff;
ptregs.xes &= 0xffff;
tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;
}
+/*
+ * This function selects if the context switch from prev to next
+ * has to tweak the TSC disable bit in the cr4.
+ */
+static inline void disable_tsc(struct task_struct *prev_p,
+ struct task_struct *next_p)
+{
+ struct thread_info *prev, *next;
+
+ /*
+ * gcc should eliminate the ->thread_info dereference if
+ * has_secure_computing returns 0 at compile time (SECCOMP=n).
+ */
+ prev = task_thread_info(prev_p);
+ next = task_thread_info(next_p);
+
+ if (has_secure_computing(prev) || has_secure_computing(next)) {
+ /* slow path here */
+ if (has_secure_computing(prev) &&
+ !has_secure_computing(next)) {
+ write_cr4(read_cr4() & ~X86_CR4_TSD);
+ } else if (!has_secure_computing(prev) &&
+ has_secure_computing(next))
+ write_cr4(read_cr4() | X86_CR4_TSD);
+ }
+}
+
/*
* switch_to(x,yn) should switch tasks from x to y.
*
/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */
__unlazy_fpu(prev_p);
+ if (next_p->mm)
+ load_user_cs_desc(cpu, next_p->mm);
/*
- * Reload esp0, LDT and the page table pointer:
+ * Reload esp0.
*/
load_esp0(tss, next);
/*
- * Load the per-thread Thread-Local Storage descriptor.
+ * Save away %fs and %gs. No need to save %es and %ds, as
+ * those are always kernel segments while inside the kernel.
+ * Doing this before setting the new TLS descriptors avoids
+ * the situation where we temporarily have non-reloadable
+ * segments in %fs and %gs. This could be an issue if the
+ * NMI handler ever used %fs or %gs (it does not today), or
+ * if the kernel is running inside of a hypervisor layer.
*/
- load_TLS(next, cpu);
+ savesegment(fs, prev->fs);
+ savesegment(gs, prev->gs);
/*
- * Save away %fs and %gs. No need to save %es and %ds, as
- * those are always kernel segments while inside the kernel.
+ * Load the per-thread Thread-Local Storage descriptor.
*/
- asm volatile("mov %%fs,%0":"=m" (prev->fs));
- asm volatile("mov %%gs,%0":"=m" (prev->gs));
+ load_TLS(next, cpu);
/*
* Restore %fs and %gs if needed.
+ *
+ * Glibc normally makes %fs be zero, and %gs is one of
+ * the TLS segments.
*/
- if (unlikely(prev->fs | prev->gs | next->fs | next->gs)) {
+ if (unlikely(prev->fs | next->fs))
loadsegment(fs, next->fs);
+
+ if (prev->gs | next->gs)
loadsegment(gs, next->gs);
- }
+
+ /*
+ * Restore IOPL if needed.
+ */
+ if (unlikely(prev->iopl != next->iopl))
+ set_iopl_mask(next->iopl);
/*
* Now maybe reload the debug registers
*/
if (unlikely(next->debugreg[7])) {
- loaddebug(next, 0);
- loaddebug(next, 1);
- loaddebug(next, 2);
- loaddebug(next, 3);
+ set_debugreg(next->debugreg[0], 0);
+ set_debugreg(next->debugreg[1], 1);
+ set_debugreg(next->debugreg[2], 2);
+ set_debugreg(next->debugreg[3], 3);
/* no 4 and 5 */
- loaddebug(next, 6);
- loaddebug(next, 7);
+ set_debugreg(next->debugreg[6], 6);
+ set_debugreg(next->debugreg[7], 7);
}
if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr))
handle_io_bitmap(next, tss);
+ disable_tsc(prev_p, next_p);
+
return prev_p;
}
int count = 0;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
- stack_page = (unsigned long)p->thread_info;
+ stack_page = (unsigned long)task_stack_page(p);
esp = p->thread.esp;
if (!stack_page || esp < stack_page || esp > top_esp+stack_page)
return 0;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
+ memset(&info, 0, sizeof(info));
+
desc = current->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
info.entry_number = idx;
sp -= get_random_int() % 8192;
return sp & ~0xf;
}
+
+void arch_add_exec_range(struct mm_struct *mm, unsigned long limit)
+{
+ if (limit > mm->context.exec_limit) {
+ mm->context.exec_limit = limit;
+ set_user_cs(&mm->context.user_cs, limit);
+ if (mm == current->mm) {
+ preempt_disable();
+ load_user_cs_desc(smp_processor_id(), mm);
+ preempt_enable();
+ }
+ }
+}
+
+void arch_remove_exec_range(struct mm_struct *mm, unsigned long old_end)
+{
+ struct vm_area_struct *vma;
+ unsigned long limit = PAGE_SIZE;
+
+ if (old_end == mm->context.exec_limit) {
+ for (vma = mm->mmap; vma; vma = vma->vm_next)
+ if ((vma->vm_flags & VM_EXEC) && (vma->vm_end > limit))
+ limit = vma->vm_end;
+
+ mm->context.exec_limit = limit;
+ set_user_cs(&mm->context.user_cs, limit);
+ if (mm == current->mm) {
+ preempt_disable();
+ load_user_cs_desc(smp_processor_id(), mm);
+ preempt_enable();
+ }
+ }
+}
+
+void arch_flush_exec_range(struct mm_struct *mm)
+{
+ mm->context.exec_limit = 0;
+ set_user_cs(&mm->context.user_cs, 0);
+}
+
+/*
+ * Generate random brk address between 128MB and 196MB. (if the layout
+ * allows it.)
+ */
+void randomize_brk(unsigned long old_brk)
+{
+ unsigned long new_brk, range_start, range_end;
+
+ range_start = 0x08000000;
+ if (current->mm->brk >= range_start)
+ range_start = current->mm->brk;
+ range_end = range_start + 0x02000000;
+ new_brk = randomize_range(range_start, range_end, 0);
+ if (new_brk)
+ current->mm->brk = new_brk;
+}
+
git://git.onelab.eu / linux-2.6.git / blobdiff