diff options
Diffstat (limited to 'drivers/acpi/acpi_pad.c')
| -rw-r--r-- | drivers/acpi/acpi_pad.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c index 62122134693..d269a8f3329 100644 --- a/drivers/acpi/acpi_pad.c +++ b/drivers/acpi/acpi_pad.c @@ -43,6 +43,10 @@ static DEFINE_MUTEX(isolated_cpus_lock); #define CPUID5_ECX_EXTENSIONS_SUPPORTED (0x1) #define CPUID5_ECX_INTERRUPT_BREAK (0x2) static unsigned long power_saving_mwait_eax; + +static unsigned char tsc_detected_unstable; +static unsigned char tsc_marked_unstable; + static void power_saving_mwait_init(void) { unsigned int eax, ebx, ecx, edx; @@ -87,8 +91,8 @@ static void power_saving_mwait_init(void) /*FALL THROUGH*/ default: - /* TSC could halt in idle, so notify users */ - mark_tsc_unstable("TSC halts in idle"); + /* TSC could halt in idle */ + tsc_detected_unstable = 1; } #endif } @@ -168,16 +172,14 @@ static int power_saving_thread(void *data) do_sleep = 0; - current_thread_info()->status &= ~TS_POLLING; - /* - * TS_POLLING-cleared state must be visible before we test - * NEED_RESCHED: - */ - smp_mb(); - expire_time = jiffies + HZ * (100 - idle_pct) / 100; while (!need_resched()) { + if (tsc_detected_unstable && !tsc_marked_unstable) { + /* TSC could halt in idle, so notify users */ + mark_tsc_unstable("TSC halts in idle"); + tsc_marked_unstable = 1; + } local_irq_disable(); cpu = smp_processor_id(); clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, @@ -200,8 +202,6 @@ static int power_saving_thread(void *data) } } - current_thread_info()->status |= TS_POLLING; - /* * current sched_rt has threshold for rt task running time. * When a rt task uses 95% CPU time, the rt thread will be |