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| author | Ingo Molnar <mingo@elte.hu> | 2009-09-22 15:50:24 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-11-09 16:23:07 -0800 |
| commit | 49fae454bb8ca92b5ff999cc823ac60caf2ccb61 (patch) | |
| tree | 81edaa89b506c687635d2aaac42e8bbd15400bd2 | |
| parent | fe2414ca987a3a49007bec6fd12254c7defae2a9 (diff) | |
| download | lwn-49fae454bb8ca92b5ff999cc823ac60caf2ccb61.tar.gz lwn-49fae454bb8ca92b5ff999cc823ac60caf2ccb61.zip | |
x86: mce: Fix thermal throttling message storm
commit b417c9fd8690637f0c91479435ab3e2bf450c038 upstream.
If a system switches back and forth between hot and cold mode,
the MCE code will print a stream of critical kernel messages.
Extend the throttling code to properly notice this, by
only printing the first hot + cold transition and omitting
the rest up to CHECK_INTERVAL (5 minutes).
This way we'll only get a single incident of:
[ 102.356584] CPU0: Temperature above threshold, cpu clock throttled (total events = 1)
[ 102.357000] Disabling lock debugging due to kernel taint
[ 102.369223] CPU0: Temperature/speed normal
Every 5 minutes. The 'total events' count tells the number of cold/hot
transitions detected, should overheating occur after 5 minutes again:
[ 402.357580] CPU0: Temperature above threshold, cpu clock throttled (total events = 24891)
[ 402.358001] CPU0: Temperature/speed normal
[ 450.704142] Machine check events logged
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/therm_throt.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c index 2951436ac0e3..600e7245de6d 100644 --- a/arch/x86/kernel/cpu/mcheck/therm_throt.c +++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c @@ -42,6 +42,7 @@ struct thermal_state { u64 next_check; unsigned long throttle_count; + unsigned long last_throttle_count; }; static DEFINE_PER_CPU(struct thermal_state, thermal_state); @@ -120,11 +121,12 @@ static int therm_throt_process(bool is_throttled) if (is_throttled) state->throttle_count++; - if (!(was_throttled ^ is_throttled) && - time_before64(now, state->next_check)) + if (time_before64(now, state->next_check) && + state->throttle_count != state->last_throttle_count) return 0; state->next_check = now + CHECK_INTERVAL; + state->last_throttle_count = state->throttle_count; /* if we just entered the thermal event */ if (is_throttled) { |