From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753601Ab3EFQ2L (ORCPT ); Mon, 6 May 2013 12:28:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59607 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754379Ab3EFQ2F (ORCPT ); Mon, 6 May 2013 12:28:05 -0400 From: Jiri Olsa To: linux-kernel@vger.kernel.org Cc: Jiri Olsa , Arnaldo Carvalho de Melo , Namhyung Kim , Corey Ashford , Frederic Weisbecker , Ingo Molnar , Paul Mackerras , Peter Zijlstra , Stephane Eranian , Borislav Petkov Subject: [PATCH 1/2] perf: Fix EXIT event notification Date: Mon, 6 May 2013 18:27:17 +0200 Message-Id: <1367857638-27631-2-git-send-email-jolsa@redhat.com> In-Reply-To: <1367857638-27631-1-git-send-email-jolsa@redhat.com> References: <1367857638-27631-1-git-send-email-jolsa@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The perf_event_task_ctx 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 Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Borislav Petkov --- 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(); } -- 1.7.11.7