From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754789Ab1E1Qip (ORCPT ); Sat, 28 May 2011 12:38:45 -0400 Received: from hera.kernel.org ([140.211.167.34]:32944 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754144Ab1E1Qin (ORCPT ); Sat, 28 May 2011 12:38:43 -0400 Date: Sat, 28 May 2011 16:38:28 GMT From: tip-bot for Peter Zijlstra Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, oleg@redhat.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, tglx@linutronix.de, oleg@redhat.com, mingo@elte.hu In-Reply-To: <20110409192141.665385503@chello.nl> References: <20110409192141.665385503@chello.nl> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf: Optimize ctx_sched_out() Git-Commit-ID: 075e0b00857e166dcc3e39037a1fc5a90acac709 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Sat, 28 May 2011 16:38:29 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 075e0b00857e166dcc3e39037a1fc5a90acac709 Gitweb: http://git.kernel.org/tip/075e0b00857e166dcc3e39037a1fc5a90acac709 Author: Peter Zijlstra AuthorDate: Sat, 9 Apr 2011 21:17:40 +0200 Committer: Ingo Molnar CommitDate: Sat, 28 May 2011 18:01:09 +0200 perf: Optimize ctx_sched_out() Oleg noted that ctx_sched_out() disables the PMU even though it might not actually do something, avoid needless PMU-disabling. Reported-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20110409192141.665385503@chello.nl Signed-off-by: Ingo Molnar --- kernel/events/core.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index d863b3c..4d9a1f01 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1760,7 +1760,6 @@ static void ctx_sched_out(struct perf_event_context *ctx, struct perf_event *event; raw_spin_lock(&ctx->lock); - perf_pmu_disable(ctx->pmu); ctx->is_active = 0; if (likely(!ctx->nr_events)) goto out; @@ -1770,6 +1769,7 @@ static void ctx_sched_out(struct perf_event_context *ctx, if (!ctx->nr_active) goto out; + perf_pmu_disable(ctx->pmu); if (event_type & EVENT_PINNED) { list_for_each_entry(event, &ctx->pinned_groups, group_entry) group_sched_out(event, cpuctx, ctx); @@ -1779,8 +1779,8 @@ static void ctx_sched_out(struct perf_event_context *ctx, list_for_each_entry(event, &ctx->flexible_groups, group_entry) group_sched_out(event, cpuctx, ctx); } -out: perf_pmu_enable(ctx->pmu); +out: raw_spin_unlock(&ctx->lock); }