The patch titled acpi: fix pmtimer overflow which makes Cx states time incorrect has been removed from the -mm tree. Its filename was acpi-fix-pmtimer-overflow-which-makes-cx-states-time-incorrect.patch This patch was dropped because other changes were merged, which wrecked this patch The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: acpi: fix pmtimer overflow which makes Cx states time incorrect From: "alex.shi" <alex.shi@xxxxxxxxx> On most boxes the ACPI PM timer is 24-bit counter that runs on 3.579545MHz clock. In such case the max C-state sleep time should be less than 4687ms when it is used to record C2/C3 duration time. But on some boxes the max C-state sleep time is more than 4687ms. In such case the overflow happens and the C-state duration time can't be counted accurately. Use clocksource to get the C-state time instead of ACPI PM timer. and use div64_u64 to convert US_TO_PM_TIME_TICKS in i386 mode. Asked-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx> Tested-by: Alex Shi <alex.shi@xxxxxxxxx> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx> Signed-off-by: Yakui.zhao <yakui.zhao@xxxxxxxxx> Cc: Len Brown <lenb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/acpi/processor_idle.c | 60 ++++++++++++++++++-------------- 1 file changed, 35 insertions(+), 25 deletions(-) diff -puN drivers/acpi/processor_idle.c~acpi-fix-pmtimer-overflow-which-makes-cx-states-time-incorrect drivers/acpi/processor_idle.c --- a/drivers/acpi/processor_idle.c~acpi-fix-pmtimer-overflow-which-makes-cx-states-time-incorrect +++ a/drivers/acpi/processor_idle.c @@ -64,7 +64,8 @@ #define _COMPONENT ACPI_PROCESSOR_COMPONENT 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 US_TO_PM_TIMER_TICKS(t) div64_u64(\ + (t * (PM_TIMER_FREQUENCY/1000)), 1000ULL) #define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) #ifndef CONFIG_CPU_IDLE #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ @@ -376,8 +377,9 @@ static void acpi_processor_idle(void) struct acpi_processor *pr = NULL; struct acpi_processor_cx *cx = NULL; struct acpi_processor_cx *next_state = NULL; - int sleep_ticks = 0; - u32 t1, t2 = 0; + s64 sleep_ticks = 0; + ktime_t kt1, kt2; + s64 idle_time; /* * Interrupts must be disabled during bus mastering calculations and @@ -524,14 +526,15 @@ static void acpi_processor_idle(void) case ACPI_STATE_C2: /* Get start time (ticks) */ - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt1 = ktime_get_real(); /* 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); /* Get end time (ticks) */ - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt2 = ktime_get_real(); + idle_time = ktime_to_us(ktime_sub(kt2, kt1)); #if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) /* TSC halts in C2, so notify users */ @@ -539,7 +542,7 @@ static void acpi_processor_idle(void) mark_tsc_unstable("possible TSC halt in C2"); #endif /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = ticks_elapsed(t1, t2); + sleep_ticks = US_TO_PM_TIMER_TICKS(idle_time); /* Tell the scheduler how much we idled: */ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); @@ -585,13 +588,14 @@ static void acpi_processor_idle(void) } /* Get start time (ticks) */ - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt1 = ktime_get_real(); /* Invoke C3 */ /* 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); + kt2 = ktime_get_real(); + idle_time = ktime_to_us(ktime_sub(kt2, kt1)); if (pr->flags.bm_check && pr->flags.bm_control) { /* Enable bus master arbitration */ atomic_dec(&c3_cpu_count); @@ -604,7 +608,7 @@ static void acpi_processor_idle(void) mark_tsc_unstable("TSC halts in C3"); #endif /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = ticks_elapsed(t1, t2); + sleep_ticks = US_TO_PM_TIMER_TICKS(idle_time); /* Tell the scheduler how much we idled: */ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); @@ -1424,7 +1428,8 @@ static inline void acpi_idle_do_entry(st static int acpi_idle_enter_c1(struct cpuidle_device *dev, struct cpuidle_state *state) { - u32 t1, t2; + ktime_t kt1, kt2; + s64 idle_time; struct acpi_processor *pr; struct acpi_processor_cx *cx = cpuidle_get_statedata(state); @@ -1442,14 +1447,15 @@ static int acpi_idle_enter_c1(struct cpu return 0; } - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt1 = ktime_get_real(); acpi_idle_do_entry(cx); - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt2 = ktime_get_real(); + idle_time = ktime_to_us(ktime_sub(kt2, kt1)); local_irq_enable(); cx->usage++; - return ticks_elapsed_in_us(t1, t2); + return idle_time; } /** @@ -1462,8 +1468,9 @@ static int acpi_idle_enter_simple(struct { struct acpi_processor *pr; struct acpi_processor_cx *cx = cpuidle_get_statedata(state); - u32 t1, t2; - int sleep_ticks = 0; + ktime_t kt1, kt2; + s64 idle_time; + s64 sleep_ticks = 0; pr = __get_cpu_var(processors); @@ -1496,18 +1503,19 @@ static int acpi_idle_enter_simple(struct if (cx->type == ACPI_STATE_C3) ACPI_FLUSH_CPU_CACHE(); - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt1 = ktime_get_real(); /* Tell the scheduler that we are going deep-idle: */ sched_clock_idle_sleep_event(); acpi_idle_do_entry(cx); - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt2 = ktime_get_real(); + idle_time = ktime_to_us(ktime_sub(kt2, kt1)); #if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) /* TSC could halt in idle, so notify users */ if (tsc_halts_in_c(cx->type)) mark_tsc_unstable("TSC halts in idle");; #endif - sleep_ticks = ticks_elapsed(t1, t2); + sleep_ticks = US_TO_PM_TIMER_TICKS(idle_time); /* Tell the scheduler how much we idled: */ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); @@ -1519,7 +1527,7 @@ static int acpi_idle_enter_simple(struct acpi_state_timer_broadcast(pr, cx, 0); cx->time += sleep_ticks; - return ticks_elapsed_in_us(t1, t2); + return idle_time; } static int c3_cpu_count; @@ -1537,8 +1545,9 @@ static int acpi_idle_enter_bm(struct cpu { struct acpi_processor *pr; struct acpi_processor_cx *cx = cpuidle_get_statedata(state); - u32 t1, t2; - int sleep_ticks = 0; + ktime_t kt1, kt2; + s64 idle_time; + s64 sleep_ticks = 0; pr = __get_cpu_var(processors); @@ -1605,9 +1614,10 @@ static int acpi_idle_enter_bm(struct cpu ACPI_FLUSH_CPU_CACHE(); } - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt1 = ktime_get_real(); acpi_idle_do_entry(cx); - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + kt2 = ktime_get_real(); + idle_time = ktime_to_us(ktime_sub(kt2, kt1)); /* Re-enable bus master arbitration */ if (pr->flags.bm_check && pr->flags.bm_control) { @@ -1622,7 +1632,7 @@ static int acpi_idle_enter_bm(struct cpu if (tsc_halts_in_c(ACPI_STATE_C3)) mark_tsc_unstable("TSC halts in idle"); #endif - sleep_ticks = ticks_elapsed(t1, t2); + sleep_ticks = US_TO_PM_TIMER_TICKS(idle_time); /* Tell the scheduler how much we idled: */ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); @@ -1633,7 +1643,7 @@ static int acpi_idle_enter_bm(struct cpu acpi_state_timer_broadcast(pr, cx, 0); cx->time += sleep_ticks; - return ticks_elapsed_in_us(t1, t2); + return idle_time; } struct cpuidle_driver acpi_idle_driver = { _ Patches currently in -mm which might be from alex.shi@xxxxxxxxx are acpi-fix-pmtimer-overflow-which-makes-cx-states-time-incorrect.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html