From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757940Ab0EGSmx (ORCPT ); Fri, 7 May 2010 14:42:53 -0400 Received: from hera.kernel.org ([140.211.167.34]:46465 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757916Ab0EGSmu (ORCPT ); Fri, 7 May 2010 14:42:50 -0400 Date: Fri, 7 May 2010 18:41:36 GMT From: tip-bot for Peter Zijlstra Cc: linux-kernel@vger.kernel.org, eranian@google.com, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, eranian@google.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com, mingo@elte.hu In-Reply-To: <1273160566.5605.404.camel@twins> References: <1273160566.5605.404.camel@twins> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf: Fix exit() vs PERF_FORMAT_GROUP Message-ID: Git-Commit-ID: 4fd38e4595e2f6c9d27732c042a0e16b2753049c 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, 07 May 2010 18:41:36 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4fd38e4595e2f6c9d27732c042a0e16b2753049c Gitweb: http://git.kernel.org/tip/4fd38e4595e2f6c9d27732c042a0e16b2753049c Author: Peter Zijlstra AuthorDate: Thu, 6 May 2010 17:31:38 +0200 Committer: Ingo Molnar CommitDate: Fri, 7 May 2010 11:30:17 +0200 perf: Fix exit() vs PERF_FORMAT_GROUP Both Stephane and Corey reported that PERF_FORMAT_GROUP didn't work as expected if the task the counters were attached to quit before the read() call. The cause is that we unconditionally destroy the grouping when we remove counters from their context. Fix this by only doing this when we free the counter itself. Reported-by: Corey Ashford Reported-by: Stephane Eranian Signed-off-by: Peter Zijlstra LKML-Reference: <1273160566.5605.404.camel@twins> Signed-off-by: Ingo Molnar --- include/linux/perf_event.h | 1 + kernel/perf_event.c | 5 +++++ 2 files changed, 6 insertions(+), 0 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index c8e3754..bf8f3c0 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -522,6 +522,7 @@ struct pmu { * enum perf_event_active_state - the states of a event */ enum perf_event_active_state { + PERF_EVENT_STATE_FREE = -3, PERF_EVENT_STATE_ERROR = -2, PERF_EVENT_STATE_OFF = -1, PERF_EVENT_STATE_INACTIVE = 0, diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 3d1552d..f13c3db 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -341,6 +341,9 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx) if (event->state > PERF_EVENT_STATE_OFF) event->state = PERF_EVENT_STATE_OFF; + if (event->state > PERF_EVENT_STATE_FREE) + return; + /* * If this was a group event with sibling events then * upgrade the siblings to singleton events by adding them @@ -1856,6 +1859,8 @@ int perf_event_release_kernel(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; + event->state = PERF_EVENT_STATE_FREE; + WARN_ON_ONCE(ctx->parent_ctx); mutex_lock(&ctx->mutex); perf_event_remove_from_context(event);