From patchwork Wed Aug 1 00:09:38 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 1262611 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 4D20E3FC81 for ; Wed, 1 Aug 2012 00:10:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756292Ab2HAAJl (ORCPT ); Tue, 31 Jul 2012 20:09:41 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:22603 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756262Ab2HAAJj (ORCPT ); Tue, 31 Jul 2012 20:09:39 -0400 X-Authority-Analysis: v=2.0 cv=ZuBv2qHG c=1 sm=0 a=s5Htg7xnQOKvHEu9STBOug==:17 a=OpT9cpI26MMA:10 a=3Odpp9koIGIA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=ayC55rCoAAAA:8 a=uIdlduh3AAAA:8 a=nq487Jr5AAAA:8 a=Xu5BC2pl9BZUGKQenEYA:9 a=PUjeQqilurYA:10 a=BpkDXmdOPbQA:10 a=hv2zDS4UK48A:10 a=s5Htg7xnQOKvHEu9STBOug==:117 X-Cloudmark-Score: 0 X-Originating-IP: 72.230.195.127 Received: from [72.230.195.127] ([72.230.195.127:60960] helo=[192.168.23.10]) by hrndva-oedge04.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id 04/54-21135-2C378105; Wed, 01 Aug 2012 00:09:39 +0000 Message-ID: <1343779778.27983.73.camel@gandalf.stny.rr.com> Subject: Re: Testing tracer wakeup_rt: .. no entries found ..FAILED! From: Steven Rostedt To: paulmck@linux.vnet.ibm.com Cc: Fengguang Wu , Avi Kivity , Steven Rostedt , LKML , "kvm@vger.kernel.org" Date: Tue, 31 Jul 2012 20:09:38 -0400 In-Reply-To: <20120731235705.GW2422@linux.vnet.ibm.com> References: <20120724090330.GA9830@localhost> <20120724090720.GA10434@localhost> <1343663105.3847.7.camel@fedora> <20120731121759.GA17822@localhost> <5017D19B.5080806@redhat.com> <1343738627.27983.30.camel@gandalf.stny.rr.com> <5017D4AB.3090107@redhat.com> <1343740419.27983.33.camel@gandalf.stny.rr.com> <20120731234336.GA5526@localhost> <1343778699.27983.70.camel@gandalf.stny.rr.com> <20120731235705.GW2422@linux.vnet.ibm.com> X-Mailer: Evolution 3.4.3-1 Mime-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, 2012-07-31 at 16:57 -0700, Paul E. McKenney wrote: > > What was the next lines? I bet you it was "PASSED". Which means it did > > not fail. This is the second bug you found that has to do with RCU being > > called in 'idle'. The one that Paul posted a patch for. > > Though it needs another patch to actually use it in the right place... Right. Something like this: -- Steve --- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5638104..d915638 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -631,7 +631,12 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); max_data->pid = tsk->pid; - max_data->uid = task_uid(tsk); + /* + * task_uid() calls rcu_read_lock, but this can be called + * outside of RCU state monitoring (irq going back to idle). + */ + RCU_NONIDLE(max_data->uid = task_uid(tsk)); + max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; max_data->policy = tsk->policy; max_data->rt_priority = tsk->rt_priority;