From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DEF6C200B88 for ; Wed, 13 Nov 2024 13:43:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731505428; cv=none; b=DygFDUkqMRtzAm69D5/ogsBGiw0S5vOrgOzpbAwoNtVViEC93yeHKr/5eIu/QdFSTCsHeFSBfRikBt1Yc1NE/UkoJPpusACWjaRgLoXuY1R96iEhw86oXFYAXMhOlisLue3/58GUrjN1ZPW/ZPAal/rwLnCCc0xBBFZ6fLz3y2g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731505428; c=relaxed/simple; bh=+zMnvloxaCSpMvgyYqLs2QHpUg7QBnvW/fUxPVrsfkI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tvlS+grv0BuLgvDTDGSR6CM4c4oWyKEkWbbX4D8lfp8gorV2GGCED0R810K+f3RLHGa93kAjvM8n4n+KcPq+74PsD5VFw0ecbyApRXkLekznUNVW/XMdBcpuyRhl9xbivoEXfMSX8nc9dUgDxB+WmHsNSut0UiUQ6YUQDYdyC2I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=b9qUd4aD; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="b9qUd4aD" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1731505425; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=HmOevJufZu4mgzJjDlfEl6PeJBrFET9QpgN5rfl3zyI=; b=b9qUd4aDNeJsHB41SZ9JGVWgaRggwOFYkyC+zouyTNAnyA+Taucg7Frct1pmo7FkQSEeHQ 7bPOyBRwnn+cdRhoxyInLiTIuz3X13bGpQJyl2KBvOxCw+trxaSzaaVkZzf8zUkkmvwB2O j3K5X9EO3eZgqfJ8hdrh9NiIhDhnYp8= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-62-h_azobdlPSW14nOoMzrrTg-1; Wed, 13 Nov 2024 08:43:39 -0500 X-MC-Unique: h_azobdlPSW14nOoMzrrTg-1 X-Mimecast-MFC-AGG-ID: h_azobdlPSW14nOoMzrrTg Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0C7841955F3A; Wed, 13 Nov 2024 13:43:36 +0000 (UTC) Received: from pauld.westford.csb (unknown [10.22.80.158]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5F6FC19560A3; Wed, 13 Nov 2024 13:43:31 +0000 (UTC) Date: Wed, 13 Nov 2024 08:43:28 -0500 From: Phil Auld To: Juri Lelli Cc: Waiman Long , Tejun Heo , Johannes Weiner , Michal Koutny , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Qais Yousef , Sebastian Andrzej Siewior , "Joel Fernandes (Google)" , Suleiman Souhlal , Aashish Sharma , Shin Kawamura , Vineeth Remanan Pillai , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: Re: [PATCH 1/2] sched/deadline: Restore dl_server bandwidth on non-destructive root domain changes Message-ID: <20241113134328.GA402105@pauld.westford.csb> References: <20241113125724.450249-1-juri.lelli@redhat.com> <20241113125724.450249-2-juri.lelli@redhat.com> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241113125724.450249-2-juri.lelli@redhat.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Hi Juri, On Wed, Nov 13, 2024 at 12:57:22PM +0000 Juri Lelli wrote: > When root domain non-destructive changes (e.g., only modifying one of > the existing root domains while the rest is not touched) happen we still > need to clear DEADLINE bandwidth accounting so that it's then properly > restore taking into account DEADLINE tasks associated to each cpuset "restored, taking ..." ? > (associated to each root domain). After the introduction of dl_servers, > we fail to restore such servers contribution after non-destructive > changes (as they are only considered on destructive changes when > runqueues are attached to the new domains). > > Fix this by making sure we iterate over the dl_server attached to > domains that have not been destroyed and add them bandwidth contribution > back correctly. > > Signed-off-by: Juri Lelli Looks good to me. Reviewed-by: Phil Auld > --- > include/linux/sched/deadline.h | 2 +- > kernel/cgroup/cpuset.c | 2 +- > kernel/sched/deadline.c | 18 +++++++++++++----- > kernel/sched/topology.c | 10 ++++++---- > 4 files changed, 21 insertions(+), 11 deletions(-) > > diff --git a/include/linux/sched/deadline.h b/include/linux/sched/deadline.h > index 3a912ab42bb5..82c966a55856 100644 > --- a/include/linux/sched/deadline.h > +++ b/include/linux/sched/deadline.h > @@ -33,7 +33,7 @@ static inline bool dl_time_before(u64 a, u64 b) > > struct root_domain; > extern void dl_add_task_root_domain(struct task_struct *p); > -extern void dl_clear_root_domain(struct root_domain *rd); > +extern void dl_clear_root_domain(struct root_domain *rd, bool restore); > > #endif /* CONFIG_SMP */ > > diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c > index 142303abb055..4d3603a99db3 100644 > --- a/kernel/cgroup/cpuset.c > +++ b/kernel/cgroup/cpuset.c > @@ -954,7 +954,7 @@ static void dl_rebuild_rd_accounting(void) > * Clear default root domain DL accounting, it will be computed again > * if a task belongs to it. > */ > - dl_clear_root_domain(&def_root_domain); > + dl_clear_root_domain(&def_root_domain, false); > > cpuset_for_each_descendant_pre(cs, pos_css, &top_cpuset) { > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index 9ce93d0bf452..e53208a50279 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -2968,13 +2968,21 @@ void dl_add_task_root_domain(struct task_struct *p) > task_rq_unlock(rq, p, &rf); > } > > -void dl_clear_root_domain(struct root_domain *rd) > +void dl_clear_root_domain(struct root_domain *rd, bool restore) > { > - unsigned long flags; > - > - raw_spin_lock_irqsave(&rd->dl_bw.lock, flags); > + guard(raw_spinlock_irqsave)(&rd->dl_bw.lock); > rd->dl_bw.total_bw = 0; > - raw_spin_unlock_irqrestore(&rd->dl_bw.lock, flags); > + > + if (restore) { > + int i; > + > + for_each_cpu(i, rd->span) { > + struct sched_dl_entity *dl_se = &cpu_rq(i)->fair_server; > + > + if (dl_server(dl_se)) > + rd->dl_bw.total_bw += dl_se->dl_bw; > + } > + } > } > > #endif /* CONFIG_SMP */ > diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c > index 9748a4c8d668..e9e7a7c43dd6 100644 > --- a/kernel/sched/topology.c > +++ b/kernel/sched/topology.c > @@ -2721,12 +2721,14 @@ void partition_sched_domains_locked(int ndoms_new, cpumask_var_t doms_new[], > > /* > * This domain won't be destroyed and as such > - * its dl_bw->total_bw needs to be cleared. It > - * will be recomputed in function > - * update_tasks_root_domain(). > + * its dl_bw->total_bw needs to be cleared. > + * Tasks contribution will be then recomputed > + * in function dl_update_tasks_root_domain(), > + * dl_servers contribution in function > + * dl_restore_server_root_domain(). > */ > rd = cpu_rq(cpumask_any(doms_cur[i]))->rd; > - dl_clear_root_domain(rd); > + dl_clear_root_domain(rd, true); > goto match1; > } > } > -- > 2.47.0 > > --