From: Len Brown <len.brown@xxxxxxxxx> The c2 and c3 idle handlers check tsc_halts_in_c() after every time they return from idle. Um, when?:-) Move this check to init-time to remove the unnecessary run-time overhead, and also to have the check complete before the first entry into the idle handler. ff69f2bba67bd45514923aaedbf40fe351787c59 (acpi: fix of pmtimer overflow that make Cx states time incorrect) replaced the hard-coded use of the PM-timer inside idle, with ktime_get_readl(), which possibly uses the TSC -- so it is now especially prudent to detect a broken TSC before entering idle. http://bugzilla.kernel.org/show_bug.cgi?id=13087 Signed-off-by: Len Brown <len.brown@xxxxxxxxx> --- drivers/acpi/processor_idle.c | 15 +++++---------- 1 files changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 6fe1214..9d1f01e 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -581,6 +581,11 @@ static int acpi_processor_power_verify(struct acpi_processor *pr) for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { struct acpi_processor_cx *cx = &pr->power.states[i]; +#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 switch (cx->type) { case ACPI_STATE_C1: cx->valid = 1; @@ -871,11 +876,6 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev, 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 = us_to_pm_timer_ticks(idle_time); /* Tell the scheduler how much we idled: */ @@ -989,11 +989,6 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev, spin_unlock(&c3_lock); } -#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) - /* TSC could halt in idle, so notify users */ - if (tsc_halts_in_c(ACPI_STATE_C3)) - mark_tsc_unstable("TSC halts in idle"); -#endif 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); -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
