From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 101AFC32753 for ; Mon, 12 Aug 2019 13:13:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E1E2020842 for ; Mon, 12 Aug 2019 13:13:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728911AbfHLNNS (ORCPT ); Mon, 12 Aug 2019 09:13:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50684 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728887AbfHLNNQ (ORCPT ); Mon, 12 Aug 2019 09:13:16 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F06AC7BDAE; Mon, 12 Aug 2019 13:13:15 +0000 (UTC) Received: from pauld.bos.csb (dhcp-17-51.bos.redhat.com [10.18.17.51]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2C3EF17B46; Mon, 12 Aug 2019 13:13:15 +0000 (UTC) Date: Mon, 12 Aug 2019 09:13:13 -0400 From: Phil Auld To: tglx@linutronix.de Cc: peterz@infradead.org, mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@kernel.org, vincent.guittot@linaro.org Subject: Re: [tip:sched/core] sched/fair: Use rq_lock/unlock in online_fair_sched_group Message-ID: <20190812131313.GA11058@pauld.bos.csb> References: <20190801133749.11033-1-pauld@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Mon, 12 Aug 2019 13:13:16 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 12, 2019 at 05:52:04AM -0700 tip-bot for Phil Auld wrote: > Commit-ID: a46d14eca7b75fffe35603aa8b81df654353d80f > Gitweb: https://git.kernel.org/tip/a46d14eca7b75fffe35603aa8b81df654353d80f > Author: Phil Auld > AuthorDate: Thu, 1 Aug 2019 09:37:49 -0400 > Committer: Thomas Gleixner > CommitDate: Mon, 12 Aug 2019 14:45:34 +0200 > > sched/fair: Use rq_lock/unlock in online_fair_sched_group > > Enabling WARN_DOUBLE_CLOCK in /sys/kernel/debug/sched_features causes > warning to fire in update_rq_clock. This seems to be caused by onlining > a new fair sched group not using the rq lock wrappers. > > [] rq->clock_update_flags & RQCF_UPDATED > [] WARNING: CPU: 5 PID: 54385 at kernel/sched/core.c:210 update_rq_clock+0xec/0x150 > > [] Call Trace: > [] online_fair_sched_group+0x53/0x100 > [] cpu_cgroup_css_online+0x16/0x20 > [] online_css+0x1c/0x60 > [] cgroup_apply_control_enable+0x231/0x3b0 > [] cgroup_mkdir+0x41b/0x530 > [] kernfs_iop_mkdir+0x61/0xa0 > [] vfs_mkdir+0x108/0x1a0 > [] do_mkdirat+0x77/0xe0 > [] do_syscall_64+0x55/0x1d0 > [] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Using the wrappers in online_fair_sched_group instead of the raw locking > removes this warning. > > [ tglx: Use rq_*lock_irq() ] > > Signed-off-by: Phil Auld > Signed-off-by: Peter Zijlstra (Intel) > Signed-off-by: Thomas Gleixner > Cc: Ingo Molnar > Cc: Vincent Guittot > Cc: Ingo Molnar > Link: https://lkml.kernel.org/r/20190801133749.11033-1-pauld@redhat.com > --- > kernel/sched/fair.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 19c58599e967..1054d2cf6aaa 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -10281,18 +10281,18 @@ err: > void online_fair_sched_group(struct task_group *tg) > { > struct sched_entity *se; > + struct rq_flags rf; > struct rq *rq; > int i; > > for_each_possible_cpu(i) { > rq = cpu_rq(i); > se = tg->se[i]; > - > - raw_spin_lock_irq(&rq->lock); > + rq_lock_irq(rq, &rf); > update_rq_clock(rq); > attach_entity_cfs_rq(se); > sync_throttle(tg, i); > - raw_spin_unlock_irq(&rq->lock); > + rq_unlock_irq(rq, &rf); > } > } > Thanks Thomas! --