From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933692Ab0BZK0e (ORCPT ); Fri, 26 Feb 2010 05:26:34 -0500 Received: from hera.kernel.org ([140.211.167.34]:34412 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933313Ab0BZK0S (ORCPT ); Fri, 26 Feb 2010 05:26:18 -0500 Date: Fri, 26 Feb 2010 10:25:54 GMT From: tip-bot for Peter Zijlstra Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, arjan@linux.intel.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, arjan@linux.intel.com, tglx@linutronix.de, mingo@elte.hu In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf_events, x86: Remove superflous MSR writes Message-ID: Git-Commit-ID: 6667661df4bc76083edf1e08831c20f64429709d X-Mailer: tip-git-log-daemon 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]); Fri, 26 Feb 2010 10:25:55 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 6667661df4bc76083edf1e08831c20f64429709d Gitweb: http://git.kernel.org/tip/6667661df4bc76083edf1e08831c20f64429709d Author: Peter Zijlstra AuthorDate: Wed, 10 Feb 2010 16:10:48 +0100 Committer: Ingo Molnar CommitDate: Fri, 26 Feb 2010 10:56:54 +0100 perf_events, x86: Remove superflous MSR writes We re-program the event control register every time we reset the count, this appears to be superflous, hence remove it. Signed-off-by: Peter Zijlstra Cc: Arjan van de Ven LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event.c | 3 --- 1 files changed, 0 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index ad09656..dd09ccc 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -2009,9 +2009,6 @@ static int intel_pmu_save_and_restart(struct perf_event *event) x86_perf_event_update(event, hwc, idx); ret = x86_perf_event_set_period(event, hwc, idx); - if (event->state == PERF_EVENT_STATE_ACTIVE) - intel_pmu_enable_event(hwc, idx); - return ret; }