From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932213Ab3GROf4 (ORCPT ); Thu, 18 Jul 2013 10:35:56 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:29052 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751394Ab3GROfz (ORCPT ); Thu, 18 Jul 2013 10:35:55 -0400 X-Authority-Analysis: v=2.0 cv=KJ7Y/S5o c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=vg5It6jECHwA:10 a=5SG0PmZfjMsA:10 a=IkcTkHD0fZMA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=ew_GO8iv7i0A:10 a=3nbZYyFuAAAA:8 a=cBsI9TqyZyArO2IHqjIA:9 a=QEXdDO2ut3YA:10 a=EvKJbDF4Ut8A:10 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Message-ID: <1374158153.6458.235.camel@gandalf.local.home> Subject: Re: [RFC PATCH V2] tracing/kprobe: Wait for disabling all running kprobe handlers From: Steven Rostedt To: Masami Hiramatsu 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 Date: Thu, 18 Jul 2013 10:35:53 -0400 In-Reply-To: <51E7DA79.4060505@hitachi.com> References: <20130709082149.GK25631@dyad.programming.kicks-ass.net> <20130709093526.20138.93100.stgit@mhiramat-M0-7522> <20130715182012.GB18505@redhat.com> <51E7DA79.4060505@hitachi.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2013-07-18 at 21:07 +0900, Masami Hiramatsu wrote: > (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. Sure, I'll pull that into my queue now. -- Steve