Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758883Ab3GRMHZ (ORCPT ); Thu, 18 Jul 2013 08:07:25 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:46271 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756913Ab3GRMHY (ORCPT ); Thu, 18 Jul 2013 08:07:24 -0400 Message-ID: <51E7DA79.4060505@hitachi.com> Date: Thu, 18 Jul 2013 21:07:21 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 5.2; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Steven Rostedt Cc: Oleg Nesterov , Peter Zijlstra , Frederic Weisbecker , linux-kernel@vger.kernel.org, Ingo Molnar , Arnaldo Carvalho de Melo , Andrew Morton , jovi.zhangwei@huawei.com, Jiri Olsa , Srikar Dronamraju Subject: Re: [RFC PATCH V2] tracing/kprobe: Wait for disabling all running kprobe handlers References: <20130709082149.GK25631@dyad.programming.kicks-ass.net> <20130709093526.20138.93100.stgit@mhiramat-M0-7522> <20130715182012.GB18505@redhat.com> In-Reply-To: <20130715182012.GB18505@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1230 Lines: 37 (2013/07/16 3:20), Oleg Nesterov wrote: > On 07/09, Masami Hiramatsu wrote: >> >> Wait for disabling all running kprobe handlers when a kprobe >> event is disabled, since the caller, trace_remove_event_call() >> supposes that a removing event is disabled completely by >> disabling the event. >> With this change, ftrace can ensure that there is no running >> event handlers after disabling it. >> >> Changes in V2: >> - Comment (in code) for clarify why we need to wait there. >> >> Signed-off-by: Masami Hiramatsu > > Agreed. > > We need this change in any case, whatever we do in trace/trace_events.c > and in unregister_trace_probe(). Steven, I think this patch is still needed anyway even if we are discussing file handling bugs, because this fixes another timing bug. Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.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/