From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753149AbdJ3Laj (ORCPT ); Mon, 30 Oct 2017 07:30:39 -0400 Received: from terminus.zytor.com ([65.50.211.136]:34155 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753132AbdJ3Lah (ORCPT ); Mon, 30 Oct 2017 07:30:37 -0400 Date: Mon, 30 Oct 2017 04:26:03 -0700 From: tip-bot for Tejun Heo Message-ID: Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, acme@kernel.org, peterz@infradead.org, davidcc@google.com, torvalds@linux-foundation.org, tglx@linutronix.de, tj@kernel.org, hpa@zytor.com Reply-To: hpa@zytor.com, tj@kernel.org, torvalds@linux-foundation.org, tglx@linutronix.de, peterz@infradead.org, davidcc@google.com, acme@kernel.org, linux-kernel@vger.kernel.org, mingo@kernel.org In-Reply-To: <20171028164237.GA972780@devbig577.frc2.facebook.com> References: <20171028164237.GA972780@devbig577.frc2.facebook.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf/cgroup: Fix perf cgroup hierarchy support Git-Commit-ID: be96b316deff35e119760982c43af74e606fa143 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: be96b316deff35e119760982c43af74e606fa143 Gitweb: https://git.kernel.org/tip/be96b316deff35e119760982c43af74e606fa143 Author: Tejun Heo AuthorDate: Sat, 28 Oct 2017 09:49:37 -0700 Committer: Ingo Molnar CommitDate: Mon, 30 Oct 2017 11:58:51 +0100 perf/cgroup: Fix perf cgroup hierarchy support The following commit: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") made list_update_cgroup_event() skip setting cpuctx->cgrp if no cgroup event targets %current's cgroup. This breaks perf_event's hierarchical support because events which target one of the ancestors get ignored. Fix it by using cgroup_is_descendant() test instead of equality. Signed-off-by: Tejun Heo Acked-by: Thomas Gleixner Cc: Arnaldo Carvalho de Melo Cc: David Carrillo-Cisneros Cc: Linus Torvalds Cc: Peter Zijlstra Cc: kernel-team@fb.com Cc: stable@vger.kernel.org # v4.9+ Fixes: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") Link: http://lkml.kernel.org/r/20171028164237.GA972780@devbig577.frc2.facebook.com Signed-off-by: Ingo Molnar --- kernel/events/core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 9d93db8..10cdb9c 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -901,9 +901,11 @@ list_update_cgroup_event(struct perf_event *event, cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/ if (add) { + struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); + list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); - if (perf_cgroup_from_task(current, ctx) == event->cgrp) - cpuctx->cgrp = event->cgrp; + if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) + cpuctx->cgrp = cgrp; } else { list_del(cpuctx_entry); cpuctx->cgrp = NULL;