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=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,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 E556CC0650F for ; Thu, 8 Aug 2019 07:57:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B560B218B8 for ; Thu, 8 Aug 2019 07:57:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OGIRQ+/u" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731749AbfHHH5K (ORCPT ); Thu, 8 Aug 2019 03:57:10 -0400 Received: from merlin.infradead.org ([205.233.59.134]:51220 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725796AbfHHH5F (ORCPT ); Thu, 8 Aug 2019 03:57:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=N3npgdq5SN1ktCIc9MeTH4f2H1ZhWQU8PFljfN+O3jg=; b=OGIRQ+/uj2wXA2E7NLAKpgpnt bg3dW58UxYzYyl2ITn2Qj3W4nkir7/aegwaW7/5w5JsjdIiH7ZlLYyww2/aF5e7Wvar+qydRayC7+ rl9RZssqcKtxHIDeBAEdG7Nka+BVAdgJzNHp4q+b+j487VEfiyFEA9hxIps4LR1n/ChXlCVsQ74B0 FSG7KlGYgYENY49CcVblzsmx8Z+7UmWUZWP4g8SYQWfEe6WA1Un9rGyA6j2dIDNITGAKVJu28G2DM i+1dwnVA8Bix43UC87rhkWiUe7AxV4tM/fW9vniDRyDoI1+opVLA+5F0zokLNA8zBJ+8bnvMczw9Z D48QGZ2lQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hvdHq-0007iX-W8; Thu, 08 Aug 2019 07:56:39 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id C50E49803CE; Thu, 8 Aug 2019 09:56:35 +0200 (CEST) Date: Thu, 8 Aug 2019 09:56:35 +0200 From: Peter Zijlstra To: Dietmar Eggemann Cc: mingo@kernel.org, juri.lelli@redhat.com, linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it, bristot@redhat.com, balsini@android.com, dvyukov@google.com, tglx@linutronix.de, vpillai@digitalocean.com, rostedt@goodmis.org Subject: Re: [RFC][PATCH 12/13] sched/deadline: Introduce deadline servers Message-ID: <20190808075635.GB17205@worktop.programming.kicks-ass.net> References: <20190726145409.947503076@infradead.org> <20190726161358.056107990@infradead.org> <34710762-f813-3913-0e55-fde7c91c6c2d@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <34710762-f813-3913-0e55-fde7c91c6c2d@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 07, 2019 at 06:31:59PM +0200, Dietmar Eggemann wrote: > On 7/26/19 4:54 PM, Peter Zijlstra wrote: > > > > > > Signed-off-by: Peter Zijlstra (Intel) > > [...] > > > @@ -889,6 +891,8 @@ static void update_curr(struct cfs_rq *c > > trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime); > > cgroup_account_cputime(curtask, delta_exec); > > account_group_exec_runtime(curtask, delta_exec); > > + if (curtask->server) > > + dl_server_update(curtask->server, delta_exec); > > } > > I get a lockdep_assert_held(&rq->lock) related warning in start_dl_timer() > when running the full stack. That would seem to imply a stale curtask->server value; the hunk below: --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3756,8 +3756,11 @@ pick_next_task(struct rq *rq, struct tas for_each_class(class) { p = class->pick_next_task(rq, NULL, NULL); - if (p) + if (p) { + if (p->sched_class == class && p->server) + p->server = NULL; return p; + } } Was supposed to clear p->server, but clearly something is going 'funny'.