From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964961Ab1C3Vg3 (ORCPT ); Wed, 30 Mar 2011 17:36:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:16164 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933639Ab1C3VgZ (ORCPT ); Wed, 30 Mar 2011 17:36:25 -0400 Date: Wed, 30 Mar 2011 23:35:53 +0200 From: Oleg Nesterov To: Peter Zijlstra Cc: Jiri Olsa , Paul Mackerras , Ingo Molnar , linux-kernel@vger.kernel.org, "Paul E. McKenney" Subject: Re: [PATCH,RFC] perf: panic due to inclied cpu context task_ctx value Message-ID: <20110330213553.GA20571@redhat.com> References: <20110326173545.GA22919@redhat.com> <1301164168.2250.370.camel@laptop> <20110328133033.GA8254@redhat.com> <1301324275.4859.25.camel@twins> <1301327368.4859.28.camel@twins> <20110328165648.GA9304@redhat.com> <20110330130951.GA2124@jolsa.brq.redhat.com> <1301496684.4859.192.camel@twins> <20110330163730.GA6038@redhat.com> <1301520405.4859.213.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1301520405.4859.213.camel@twins> 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 On 03/30, Peter Zijlstra wrote: > > Anyway how about we do the partial revert below that should get us back > to a working kernel and is a nice small patch to send -stable wards. > > After that we can try and be clever with clearing ->task_ctx from things > like remove_from_context and the like. > > --- > include/linux/perf_event.h | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h > index 311b4dc..04d75a8 100644 > --- a/include/linux/perf_event.h > +++ b/include/linux/perf_event.h > @@ -1086,7 +1086,7 @@ void perf_event_task_sched_out(struct task_struct *task, struct task_struct *nex > { > perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, NULL, 0); > > - COND_STMT(&perf_sched_events, __perf_event_task_sched_out(task, next)); > + __perf_event_task_sched_out(task, next); > } I agree completely. We need the simple (and suitable for stable) fix first. Oleg.