diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-05-25 17:39:05 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-05-25 21:41:12 +0200 |
| commit | a78ac3258782f3e64cb40beb5990808e1febcc0c (patch) | |
| tree | 692462a974e4c26bdb7fa7fae727a6b326a0eeee /arch | |
| parent | 48e22d56ecdeddd1ffb42a02fccba5c6ef42b133 (diff) | |
perf_counter: Generic per counter interrupt throttle
Introduce a generic per counter interrupt throttle.
This uses the perf_counter_overflow() quick disable to throttle a specific
counter when its going too fast when a pmu->unthrottle() method is provided
which can undo the quick disable.
Power needs to implement both the quick disable and the unthrottle method.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_counter.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index 8c8177f859f..c4b543d1a86 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -623,6 +623,18 @@ try_generic: return 0; } +static void x86_pmu_unthrottle(struct perf_counter *counter) +{ + struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters); + struct hw_perf_counter *hwc = &counter->hw; + + if (WARN_ON_ONCE(hwc->idx >= X86_PMC_IDX_MAX || + cpuc->counters[hwc->idx] != counter)) + return; + + x86_pmu.enable(hwc, hwc->idx); +} + void perf_counter_print_debug(void) { u64 ctrl, status, overflow, pmc_ctrl, pmc_count, prev_left, fixed; @@ -1038,6 +1050,7 @@ static const struct pmu pmu = { .enable = x86_pmu_enable, .disable = x86_pmu_disable, .read = x86_pmu_read, + .unthrottle = x86_pmu_unthrottle, }; const struct pmu *hw_perf_counter_init(struct perf_counter *counter) |