static void __exit_idle(void)
{
- if (read_pda(isidle) == 0)
+ if (test_and_clear_bit_pda(0, isidle) == 0)
return;
- write_pda(isidle, 0);
atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
}
*/
static void default_idle(void)
{
- local_irq_enable();
-
current_thread_info()->status &= ~TS_POLLING;
- smp_mb__after_clear_bit();
- while (!need_resched()) {
- local_irq_disable();
- if (!need_resched())
- safe_halt();
- else
- local_irq_enable();
- }
+ /*
+ * 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);
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
* 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();
}
}
void flush_thread(void)
{
struct task_struct *tsk = current;
- struct thread_info *t = current_thread_info();
- if (t->flags & _TIF_ABI_PENDING) {
- t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32);
- if (t->flags & _TIF_IA32)
+ if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) {
+ clear_tsk_thread_flag(tsk, TIF_ABI_PENDING);
+ if (test_tsk_thread_flag(tsk, TIF_IA32)) {
+ clear_tsk_thread_flag(tsk, TIF_IA32);
+ } else {
+ set_tsk_thread_flag(tsk, TIF_IA32);
current_thread_info()->status |= TS_COMPAT;
+ }
}
- t->flags &= ~_TIF_DEBUG;
+ clear_tsk_thread_flag(tsk, TIF_DEBUG);
tsk->thread.debugreg0 = 0;
tsk->thread.debugreg1 = 0;