From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752244Ab3EGONw (ORCPT ); Tue, 7 May 2013 10:13:52 -0400 Received: from terminus.zytor.com ([198.137.202.10]:56070 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752014Ab3EGONt (ORCPT ); Tue, 7 May 2013 10:13:49 -0400 Date: Tue, 7 May 2013 07:13:18 -0700 From: tip-bot for Jiri Olsa Message-ID: Cc: linux-kernel@vger.kernel.org, eranian@google.com, paulus@samba.org, acme@redhat.com, hpa@zytor.com, mingo@kernel.org, a.p.zijlstra@chello.nl, bp@alien8.de, namhyung@kernel.org, jolsa@redhat.com, fweisbec@gmail.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com Reply-To: mingo@kernel.org, hpa@zytor.com, acme@redhat.com, paulus@samba.org, eranian@google.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, namhyung@kernel.org, bp@alien8.de, jolsa@redhat.com, fweisbec@gmail.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com In-Reply-To: <1367857638-27631-2-git-send-email-jolsa@redhat.com> References: <1367857638-27631-2-git-send-email-jolsa@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf: Fix EXIT event notification Git-Commit-ID: 524eff183f51d080a83b348d0ea97c08b3607b9a X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 524eff183f51d080a83b348d0ea97c08b3607b9a Gitweb: http://git.kernel.org/tip/524eff183f51d080a83b348d0ea97c08b3607b9a Author: Jiri Olsa AuthorDate: Mon, 6 May 2013 18:27:17 +0200 Committer: Ingo Molnar CommitDate: Tue, 7 May 2013 13:17:28 +0200 perf: Fix EXIT event notification The perf_event_task_ctx() function needs to be called with preemption disabled, since it's checking for currently scheduled cpu against event cpu. We disable preemption for task related perf event context if there's one defined, leaving up to the chance which cpu it gets scheduled in. Signed-off-by: Jiri Olsa Acked-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Paul Mackerras Cc: Stephane Eranian Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1367857638-27631-2-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar --- kernel/events/core.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 6b41c18..38b68a0 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4474,7 +4474,7 @@ static void perf_event_task_ctx(struct perf_event_context *ctx, static void perf_event_task_event(struct perf_task_event *task_event) { struct perf_cpu_context *cpuctx; - struct perf_event_context *ctx; + struct perf_event_context *ctx, *task_ctx = task_event->task_ctx; struct pmu *pmu; int ctxn; @@ -4485,20 +4485,22 @@ static void perf_event_task_event(struct perf_task_event *task_event) goto next; perf_event_task_ctx(&cpuctx->ctx, task_event); - ctx = task_event->task_ctx; - if (!ctx) { - ctxn = pmu->task_ctx_nr; - if (ctxn < 0) - goto next; - ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); - if (ctx) - perf_event_task_ctx(ctx, task_event); - } + if (task_ctx) + goto next; + ctxn = pmu->task_ctx_nr; + if (ctxn < 0) + goto next; + ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); + if (ctx) + perf_event_task_ctx(ctx, task_event); next: put_cpu_ptr(pmu->pmu_cpu_context); } - if (task_event->task_ctx) - perf_event_task_ctx(task_event->task_ctx, task_event); + if (task_ctx) { + preempt_disable(); + perf_event_task_ctx(task_ctx, task_event); + preempt_enable(); + } rcu_read_unlock(); }