diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index a8634a0655fc..d9b8af763e1e 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -63,6 +63,7 @@ ACPI_MODULE_NAME("processor_idle"); #define ACPI_PROCESSOR_FILE_POWER "power" #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) +#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ #define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ static void (*pm_idle_save) (void) __read_mostly; @@ -462,6 +463,9 @@ static void acpi_processor_idle(void) * TBD: Can't get time duration while in C1, as resumes * go to an ISR rather than here. Need to instrument * base interrupt handler. + * + * Note: the TSC better not stop in C1, sched_clock() will + * skew otherwise. */ sleep_ticks = 0xFFFFFFFF; break; @@ -469,6 +473,8 @@ static void acpi_processor_idle(void) case ACPI_STATE_C2: /* Get start time (ticks) */ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + /* Tell the scheduler that we are going deep-idle: */ + sched_clock_idle_sleep_event(); /* Invoke C2 */ acpi_state_timer_broadcast(pr, cx, 1); acpi_cstate_enter(cx); @@ -479,17 +485,22 @@ static void acpi_processor_idle(void) /* TSC halts in C2, so notify users */ mark_tsc_unstable("possible TSC halt in C2"); #endif + /* Compute time (ticks) that we were actually asleep */ + sleep_ticks = ticks_elapsed(t1, t2); + + /* Tell the scheduler how much we idled: */ + sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); + /* Re-enable interrupts */ local_irq_enable(); + /* Do not account our idle-switching overhead: */ + sleep_ticks -= cx->latency_ticks + C2_OVERHEAD; + current_thread_info()->status |= TS_POLLING; - /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = - ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; acpi_state_timer_broadcast(pr, cx, 0); break; case ACPI_STATE_C3: - /* * disable bus master * bm_check implies we need ARB_DIS @@ -518,6 +529,8 @@ static void acpi_processor_idle(void) t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); /* Invoke C3 */ acpi_state_timer_broadcast(pr, cx, 1); + /* Tell the scheduler that we are going deep-idle: */ + sched_clock_idle_sleep_event(); acpi_cstate_enter(cx); /* Get end time (ticks) */ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); @@ -531,12 +544,17 @@ static void acpi_processor_idle(void) /* TSC halts in C3, so notify users */ mark_tsc_unstable("TSC halts in C3"); #endif + /* Compute time (ticks) that we were actually asleep */ + sleep_ticks = ticks_elapsed(t1, t2); + /* Tell the scheduler how much we idled: */ + sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); + /* Re-enable interrupts */ local_irq_enable(); + /* Do not account our idle-switching overhead: */ + sleep_ticks -= cx->latency_ticks + C3_OVERHEAD; + current_thread_info()->status |= TS_POLLING; - /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = - ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; acpi_state_timer_broadcast(pr, cx, 0); break; |