From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932191Ab0CJNXh (ORCPT ); Wed, 10 Mar 2010 08:23:37 -0500 Received: from hera.kernel.org ([140.211.167.34]:53565 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932118Ab0CJNXf (ORCPT ); Wed, 10 Mar 2010 08:23:35 -0500 Date: Wed, 10 Mar 2010 13:22:52 GMT From: tip-bot for Peter Zijlstra Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, acme@infradead.org, 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, acme@infradead.org, tglx@linutronix.de, mingo@elte.hu In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/pebs] perf, x86: Fix LBR enable/disable vs cpuc->enabled Message-ID: Git-Commit-ID: 2df202bf7520eaffcbfb07e45dfa3cfb0aeee2c0 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]); Wed, 10 Mar 2010 13:22:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 2df202bf7520eaffcbfb07e45dfa3cfb0aeee2c0 Gitweb: http://git.kernel.org/tip/2df202bf7520eaffcbfb07e45dfa3cfb0aeee2c0 Author: Peter Zijlstra AuthorDate: Sat, 6 Mar 2010 13:48:54 +0100 Committer: Ingo Molnar CommitDate: Wed, 10 Mar 2010 13:23:37 +0100 perf, x86: Fix LBR enable/disable vs cpuc->enabled We should never call ->enable with the pmu enabled, and we _can_ have ->disable called with the pmu enabled. Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: paulus@samba.org Cc: eranian@google.com Cc: robert.richter@amd.com Cc: fweisbec@gmail.com LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_intel_lbr.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c index dcec765..0145f99 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c @@ -69,7 +69,7 @@ static void intel_pmu_lbr_enable(struct perf_event *event) if (!x86_pmu.lbr_nr) return; - WARN_ON(cpuc->enabled); + WARN_ON_ONCE(cpuc->enabled); /* * Reset the LBR stack if this is the first LBR user or @@ -93,9 +93,10 @@ static void intel_pmu_lbr_disable(struct perf_event *event) return; cpuc->lbr_users--; - BUG_ON(cpuc->lbr_users < 0); - WARN_ON(cpuc->enabled); + + if (cpuc->enabled && !cpuc->lbr_users) + __intel_pmu_lbr_disable(); } static void intel_pmu_lbr_enable_all(void)