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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 7820BC282DD for ; Wed, 8 Jan 2020 13:02:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 461E620643 for ; Wed, 8 Jan 2020 13:02:49 +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="QLaS4+or" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727536AbgAHNCs (ORCPT ); Wed, 8 Jan 2020 08:02:48 -0500 Received: from merlin.infradead.org ([205.233.59.134]:36626 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726144AbgAHNCs (ORCPT ); Wed, 8 Jan 2020 08:02:48 -0500 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=RXfvehcFVw1Nh6t+COz9jrJFT3gPfoC+ft4FWH5Fqh0=; b=QLaS4+ore1Vs3ckMV89u4kwcu VuW8rUH3zNVGDoB9e1x8fxxsursBtS5eitYRjPrFpng5SC5A8EjacHrlhelh9O8yQQkOFbLjH8eYs tzZLk3mlwMgat/tQOAfk6TzGj8VVfg5TDuaXSZQcrSkcuT9jryQ6kRAWcxpoK+BsyOTvrD5DE0CnT R5keSu+W3FVbKnt1mTTRBJslgusvNHRn/pXtJUOi+ElGednQXbi5wzriWbolAN1fWxRHB8OuowDYQ OieDV2dtHHP7i2E3q1urMXjgJvnMO6xjffGZP5juxswsbfy2CHPxlCnarOfF9Sfh4i16QYCk4UbWv qILm+kV3w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1ipAyZ-0002HO-Q9; Wed, 08 Jan 2020 13:02:19 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 704573012C3; Wed, 8 Jan 2020 14:00:37 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 707A420B79C80; Wed, 8 Jan 2020 14:02:10 +0100 (CET) Date: Wed, 8 Jan 2020 14:02:10 +0100 From: Peter Zijlstra To: Steven Rostedt Cc: chenying , mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, linux-kernel@vger.kernel.org, xue.zhihong@zte.com.cn, wang.yi59@zte.com.cn, jiang.xuexin@zte.com.cn Subject: Re: [PATCH] fix share rt runtime with offline rq Message-ID: <20200108130210.GF2844@hirez.programming.kicks-ass.net> References: <1576894812-36688-1-git-send-email-chen.ying153@zte.com.cn> <20191223114030.1800b4c1@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191223114030.1800b4c1@gandalf.local.home> 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 Mon, Dec 23, 2019 at 11:40:30AM -0500, Steven Rostedt wrote: > > kernel/sched/rt.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > > index a532558..d20dc86 100644 > > --- a/kernel/sched/rt.c > > +++ b/kernel/sched/rt.c > > @@ -648,8 +648,12 @@ static void do_balance_runtime(struct rt_rq *rt_rq) > > rt_period = ktime_to_ns(rt_b->rt_period); > > for_each_cpu(i, rd->span) { > > struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i); > > + struct rq *rq = rq_of_rt_rq(iter); > > s64 diff; > > > > + if (!rq->online) > > + continue; > > + > > I think this might be papering over the real issue. Perhaps > rq_offline_rt() needs to be called for CPUs not being brought online? Yeah, very much that. Something like the below perhaps. But I really want to rip out the whole RT_CGROUP_SCHED stuff so we can start over. Perhaps the poster can explain what he's using this stuff for? --- diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 4043abe45459..96a0320cfadb 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -208,7 +208,13 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) goto err_free_rq; init_rt_rq(rt_rq); + + cpus_read_lock(); rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime; + if (!cpu_online(i)) + rt_rq->rt_runtime = RUNTIME_INF; + cpus_read_unlock(); + init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]); }