Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752418Ab2JBLxr (ORCPT ); Tue, 2 Oct 2012 07:53:47 -0400 Received: from casper.infradead.org ([85.118.1.10]:56411 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750897Ab2JBLxq convert rfc822-to-8bit (ORCPT ); Tue, 2 Oct 2012 07:53:46 -0400 Message-ID: <1349178781.7780.29.camel@twins> Subject: Re: [PATCH] perf cgroups: Fix perf_cgroup_switch schedule in warning From: Peter Zijlstra To: Jiri Olsa Cc: linux-kernel@vger.kernel.org, Frederic Weisbecker , Ingo Molnar , Paul Mackerras , Arnaldo Carvalho de Melo , Stephane Eranian Date: Tue, 02 Oct 2012 13:53:01 +0200 In-Reply-To: <20121002114218.GA5891@krava.brq.redhat.com> References: <20121002114218.GA5891@krava.brq.redhat.com> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Mailer: Evolution 3.2.2- Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1598 Lines: 43 On Tue, 2012-10-02 at 13:42 +0200, Jiri Olsa wrote: > +++ b/kernel/events/core.c > @@ -394,7 +394,8 @@ void perf_cgroup_switch(struct task_struct *task, int mode) > } > > if (mode & PERF_CGROUP_SWIN) { > - WARN_ON_ONCE(cpuctx->cgrp); > + WARN_ON_ONCE(cpuctx->cgrp && !cpuctx->ctx.is_active); > + > /* set cgrp before ctxsw in to > * allow event_filter_match() to not > * have to pass task around OK, like you mentioned this is the result of multiple PMU being able to share a cpuctx, shouldn't we in that case avoid the second loop over the cpuctx as a whole? Would something like the below do? IIRC I introduced that active_pmu for exactly such reasons.. --- kernel/events/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 7b9df35..e98f014 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -372,6 +372,8 @@ void perf_cgroup_switch(struct task_struct *task, int mode) list_for_each_entry_rcu(pmu, &pmus, entry) { cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); + if (cpuctx->active_pmu != pmu) + continue; /* * perf_cgroup_events says at least one -- 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/