Commit-ID: eb8417aa703eff5ff43d0275f19b0a8e591d818d Gitweb: http://git.kernel.org/tip/eb8417aa703eff5ff43d0275f19b0a8e591d818d Author: Peter Zijlstra <[email protected]> AuthorDate: Mon, 16 Sep 2013 09:23:02 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 20 Sep 2013 06:53:44 +0200
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 <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/cpu/perf_event_intel_ds.c | 10 +++++----- 1 file 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 f364c13..655d591 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; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
