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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,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 1BB84C43331 for ; Fri, 6 Sep 2019 09:36:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F17BD2081B for ; Fri, 6 Sep 2019 09:36:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392939AbfIFJgX (ORCPT ); Fri, 6 Sep 2019 05:36:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48832 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390186AbfIFJgW (ORCPT ); Fri, 6 Sep 2019 05:36:22 -0400 Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0A67785A07 for ; Fri, 6 Sep 2019 09:36:22 +0000 (UTC) Received: by mail-wm1-f71.google.com with SMTP id j11so865416wmh.2 for ; Fri, 06 Sep 2019 02:36:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=WQbWytPIguw6envSGQcteTUy1ypWtSImNh1vUe/FzHc=; b=WWih3HPaI1Euzv0h6HtfI3fCsXOZbdPbtxWbDk6MINxpZazIcu9SKkWNoMgdPXOex9 nwR0PJMJyIOgLtk918YIcRRg4G/uTiKZY4UgAtxD/5wvyYPNTDN9D5pp7tdd3BEHNJvp lEdZkPYTRUkxtTlZtRGtdTdJmANZxzKiLUc0FdNmEg+6UEOZBMBY4XIxjSKI7sqYyveg x77g8ia4F97UBu6Jb1bWFggfstY3nTwbtjHYwHT+OO/O9r5w1PjDRATxS3THwLveh75O SYHd6dISRefSBqxY7+UrYlHCoUt4AKz42nuDt1Su56lEI2qTQrpI0PADG9CnG17loIQn q0Tg== X-Gm-Message-State: APjAAAWgZ6ticqsXUkoPdssx9TUX5qdtUnqq4lQw9dehCDr0GCreFJRc g7HUpD5hYHbG9ThwA1/GH5wtw8lxSEjiQogXRbVe+vGV7xw6ApVBvQ61pluvy3VhFF+V3vM3N21 qBf0/4grdFtgFRxVlBdtvJToe X-Received: by 2002:adf:bc84:: with SMTP id g4mr6328611wrh.135.1567762580440; Fri, 06 Sep 2019 02:36:20 -0700 (PDT) X-Google-Smtp-Source: APXvYqw6ebR9hrhq3EGuynkS1TchFhmUwJGYBqce99rDFIJYYTrRE5FvAjm0d4WEOQTKJkXMSlu+Yg== X-Received: by 2002:adf:bc84:: with SMTP id g4mr6328592wrh.135.1567762580091; Fri, 06 Sep 2019 02:36:20 -0700 (PDT) Received: from localhost.localdomain ([2001:8a0:6c09:8c01:a3c8:c747:f7af:a580]) by smtp.gmail.com with ESMTPSA id q14sm11184622wrc.77.2019.09.06.02.36.18 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 06 Sep 2019 02:36:19 -0700 (PDT) Date: Fri, 6 Sep 2019 10:36:16 +0100 From: Juri Lelli To: Peter Zijlstra Cc: Dietmar Eggemann , mingo@kernel.org, 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: <20190906093616.GK5158@localhost.localdomain> References: <20190726145409.947503076@infradead.org> <20190726161358.056107990@infradead.org> <34710762-f813-3913-0e55-fde7c91c6c2d@arm.com> <20190808075635.GB17205@worktop.programming.kicks-ass.net> <20cc05d3-0d0f-a558-2bbe-3b72527dd9bc@arm.com> <20190808084652.GG29310@localhost.localdomain> <99a8339d-8e06-bff8-284b-1829d0683a7a@arm.com> <20190808092744.GI29310@localhost.localdomain> <20190808094546.GJ29310@localhost.localdomain> <20190830112437.GD2369@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190830112437.GD2369@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 30/08/19 13:24, Peter Zijlstra wrote: > On Thu, Aug 08, 2019 at 11:45:46AM +0200, Juri Lelli wrote: > > I'd like to take this last sentence back, I was able to run a few boot + > > hackbench + shutdown cycles with the following applied (guess too much > > debug printks around before). > > I've changed that slightly; the merged delta looks like: It looks like I had to further apply what follows on top of your latest wip-deadline branch (d3138279c7f3) to make kvm boot. --->8--- kernel/fork.c | 2 ++ kernel/sched/core.c | 3 +-- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 2852d0e76ea3..4f404fe1d9ab 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1983,6 +1983,8 @@ static __latent_entropy struct task_struct *copy_process( p->sequential_io_avg = 0; #endif + p->server = NULL; + /* Perform scheduler related setup. Assign this task to a CPU. */ retval = sched_fork(clone_flags, p); if (retval) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1fd2a8c68daf..d72579b93a9f 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3917,8 +3917,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) * This is the fast path; it cannot be a DL server pick; * therefore even if @p == @prev, ->server must be NULL. */ - if (prev->server) - p->server = NULL; + p->server = NULL; return p; }