Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753537Ab0HBP12 (ORCPT ); Mon, 2 Aug 2010 11:27:28 -0400 Received: from toq11.bellnexxia.net ([209.226.175.118]:44219 "EHLO toq11-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751151Ab0HBP11 (ORCPT ); Mon, 2 Aug 2010 11:27:27 -0400 X-Greylist: delayed 458 seconds by postgrey-1.27 at vger.kernel.org; Mon, 02 Aug 2010 11:27:26 EDT X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AvsEAMd6VkxGGNu+/2dsb2JhbACgD3LCboU5BA Date: Mon, 2 Aug 2010 11:14:46 -0400 From: Mathieu Desnoyers To: Frederic Weisbecker Cc: Ingo Molnar , LKML , Peter Zijlstra , Arnaldo Carvalho de Melo , Steven Rostedt , Li Zefan Subject: Re: [PATCH 01/12] perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call Message-ID: <20100802151445.GA11747@Krystal> References: <1280707993-6599-1-git-send-regression-fweisbec@gmail.com> <1280707993-6599-2-git-send-regression-fweisbec@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <1280707993-6599-2-git-send-regression-fweisbec@gmail.com> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.27.31-grsec (i686) X-Uptime: 11:14:27 up 117 days, 1:06, 2 users, load average: 0.10, 0.20, 0.10 User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1921 Lines: 58 * Frederic Weisbecker (fweisbec@gmail.com) wrote: > We use synchronize_sched() to ensure a tracepoint won't be called > while/after we release the perf buffers it references. > > But the tracepoint API has its own API for that: > tracepoint_synchronize_unregister(). Use it instead as it's > self-explanatory and eases maintainance. > > Signed-off-by: Frederic Weisbecker Acked-by: Mathieu Desnoyers Thanks! Mathieu > Cc: Ingo Molnar > Cc: Peter Zijlstra > Cc: Arnaldo Carvalho de Melo > Cc: Mathieu Desnoyers > Cc: Steven Rostedt > Cc: Li Zefan > --- > kernel/trace/trace_event_perf.c | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c > index 2375165..000e6e8 100644 > --- a/kernel/trace/trace_event_perf.c > +++ b/kernel/trace/trace_event_perf.c > @@ -131,10 +131,10 @@ void perf_trace_destroy(struct perf_event *p_event) > tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER); > > /* > - * Ensure our callback won't be called anymore. See > - * tracepoint_probe_unregister() and __DO_TRACE(). > + * Ensure our callback won't be called anymore. The buffers > + * will be freed after that. > */ > - synchronize_sched(); > + tracepoint_synchronize_unregister(); > > free_percpu(tp_event->perf_events); > tp_event->perf_events = NULL; > -- > 1.6.2.3 > -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/