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| author | Peter Zijlstra <peterz@infradead.org> | 2013-09-16 09:23:02 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-09-20 06:53:44 +0200 |
| commit | eb8417aa703eff5ff43d0275f19b0a8e591d818d (patch) | |
| tree | aa6f24a7a4065dde34e0df8e82df47219d693d7d /arch/x86/kernel/cpu | |
| parent | 7f2ee91f54fb56071f97bde1ef7ba7ba0d58dfe5 (diff) | |
| download | talos-obmc-linux-eb8417aa703eff5ff43d0275f19b0a8e591d818d.tar.gz talos-obmc-linux-eb8417aa703eff5ff43d0275f19b0a8e591d818d.zip | |
perf/x86/intel: Remove division from the intel_pmu_drain_pebs_nhm() hot path
Only do the division in case we have to print the result out in a warning.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-43nl31erfbajwpfj254f6zji@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/cpu')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_ds.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index f364c13ddaa6..655d591b57a0 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -944,7 +944,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs) struct perf_event *event = NULL; void *at, *top; u64 status = 0; - int bit, n; + int bit; if (!x86_pmu.pebs_active) return; @@ -954,16 +954,16 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs) ds->pebs_index = ds->pebs_buffer_base; - n = (top - at) / x86_pmu.pebs_record_size; - if (n <= 0) + if (unlikely(at > top)) return; /* * Should not happen, we program the threshold at 1 and do not * set a reset value. */ - WARN_ONCE(n > x86_pmu.max_pebs_events, - "Unexpected number of pebs records %d\n", n); + WARN_ONCE(top - at > x86_pmu.max_pebs_events * x86_pmu.pebs_record_size, + "Unexpected number of pebs records %ld\n", + (top - at) / x86_pmu.pebs_record_size); for (; at < top; at += x86_pmu.pebs_record_size) { struct pebs_record_nhm *p = at; |
