diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:30:06 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:30:06 +0100 |
| commit | 5ee613b6751cd91db4b6bd7c1dc9d2f9cf65cde2 (patch) | |
| tree | 2fa68d5c3d0e18723bed666fe087b4bbc3ed78ba /arch/x86/kernel/process_64.c | |
| parent | 53d517cdbaac704352b3d0c10fecb99e0b54572e (diff) | |
x86: idle wakeup event in the HLT loop
do a proper idle-wakeup event on HLT as well - some CPUs stop the TSC
in HLT too, not just when going through the ACPI methods.
(the ACPI idle code already does this.)
[ update the 64-bit side too, as noticed by Jiri Slaby. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/process_64.c')
| -rw-r--r-- | arch/x86/kernel/process_64.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index c2db7ef93565..40fed477f3e5 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -116,9 +116,16 @@ static void default_idle(void) 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(); + ktime_t t0, t1; + u64 t0n, t1n; + + t0 = ktime_get(); + t0n = ktime_to_ns(t0); + safe_halt(); /* enables interrupts racelessly */ + local_irq_disable(); + t1 = ktime_get(); + t1n = ktime_to_ns(t1); + sched_clock_idle_wakeup_event(t1n - t0n); } else local_irq_enable(); current_thread_info()->status |= TS_POLLING; |