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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33C97C77B78 for ; Wed, 3 May 2023 07:25:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229565AbjECHZE (ORCPT ); Wed, 3 May 2023 03:25:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229742AbjECHY3 (ORCPT ); Wed, 3 May 2023 03:24:29 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE1FF423C for ; Wed, 3 May 2023 00:23:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683098598; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BtI4BRLmm2n37T/xC2JzerXvVB+wDFInkUK+VsZeYGc=; b=LGF+S8ycdyEcjc/wmaCuecr+2Fa0nUteHfyZLioCZKSh12jHEmOWf0AYBvbDfgugDrauvP 7j6GBCXN3zPI5Mnis/3UtDm1et+pjvvEXGgVmDBj7rC1bRcA7YhK/Tc8v8dlKRoQxZ9/XX 6jkUGkEe4aaQ5oQZ7AkUx+y6XNlp/LY= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-19-Y6nrjbj8M9Wl104-2vmdbg-1; Wed, 03 May 2023 03:23:17 -0400 X-MC-Unique: Y6nrjbj8M9Wl104-2vmdbg-1 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-3f17b8d24bbso29665145e9.2 for ; Wed, 03 May 2023 00:23:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683098596; x=1685690596; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=BtI4BRLmm2n37T/xC2JzerXvVB+wDFInkUK+VsZeYGc=; b=jKSI2dFC00TsHAYvedJ0OF1PNt88Z8aSzNWy3dT//enOb6XUVxdwucTt8A+DkHlnJF NV986doTKInf13KRF6jvfVez2te5PIkuhp4zrfp0sam3Pn431s9IAjx2WpYRPdl6XeVw wHHFul3bjGsx8LI/z2SXxNYi9srcA6pdrbRlwBbf4YuxIIhKGdr0sMuy2tomOfYb9Syx tlYx+x9w3F3upV/NLVomD1COrK9OSW5r09R5/hI9fgD4VEzSaZRB5QVQ/CFWpTswX29E VR27Nrl5TBEV/DywvycZ5kj6R0IDVDCcW/xkFGu6f7M2mb9uj3hP94WqNQ2d0q4XdvXE ZvLQ== X-Gm-Message-State: AC+VfDyaM6dB7k47eOYqZWETin3QNN+uR+SAQm22NXdTsaPGzdmmxhUS eqsGwkbOEv/Ml/zYFS2x5nKXO+CT4mERRftKAOrf/Y74nTzu69hMq9pRg5+XpVhF/6/Iz4nM73L CXpTg8ZzaT7K7+EEl/VNRKtxI X-Received: by 2002:a7b:cc1a:0:b0:3f0:9564:f4f6 with SMTP id f26-20020a7bcc1a000000b003f09564f4f6mr14209878wmh.1.1683098596517; Wed, 03 May 2023 00:23:16 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7DpKI8g+kK6eMRISEIAtlDtXkzxMGEOTXXWCYO5umCCHmqBQPxDsHpwgAKeQobN5Rrq3llDA== X-Received: by 2002:a7b:cc1a:0:b0:3f0:9564:f4f6 with SMTP id f26-20020a7bcc1a000000b003f09564f4f6mr14209863wmh.1.1683098596243; Wed, 03 May 2023 00:23:16 -0700 (PDT) Received: from localhost.localdomain.com ([2a02:b127:8011:7489:32ac:78e2:be8c:a5fb]) by smtp.gmail.com with ESMTPSA id k1-20020a7bc301000000b003eddc6aa5fasm947259wmj.39.2023.05.03.00.23.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 May 2023 00:23:15 -0700 (PDT) From: Juri Lelli To: Peter Zijlstra , Ingo Molnar , Qais Yousef , Waiman Long , Tejun Heo , Zefan Li , Johannes Weiner , Hao Luo Cc: Dietmar Eggemann , Steven Rostedt , linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it, claudio@evidence.eu.com, tommaso.cucinotta@santannapisa.it, bristot@redhat.com, mathieu.poirier@linaro.org, cgroups@vger.kernel.org, Vincent Guittot , Wei Wang , Rick Yiu , Quentin Perret , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Sudeep Holla , Juri Lelli Subject: [PATCH v2 6/6] cgroup/cpuset: Free DL BW in case can_attach() fails Date: Wed, 3 May 2023 09:22:28 +0200 Message-Id: <20230503072228.115707-7-juri.lelli@redhat.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230503072228.115707-1-juri.lelli@redhat.com> References: <20230503072228.115707-1-juri.lelli@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dietmar Eggemann cpuset_can_attach() can fail. Postpone DL BW allocation until all tasks have been checked. DL BW is not allocated per-task but as a sum over all DL tasks migrating. If multiple controllers are attached to the cgroup next to the cpuset controller a non-cpuset can_attach() can fail. In this case free DL BW in cpuset_cancel_attach(). Finally, update cpuset DL task count (nr_deadline_tasks) only in cpuset_attach(). Suggested-by: Waiman Long Signed-off-by: Dietmar Eggemann Signed-off-by: Juri Lelli --- include/linux/sched.h | 2 +- kernel/cgroup/cpuset.c | 53 ++++++++++++++++++++++++++++++++++++++---- kernel/sched/core.c | 17 ++------------ 3 files changed, 51 insertions(+), 21 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 0bee06542450..2553918f0b61 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1852,7 +1852,7 @@ current_restore_flags(unsigned long orig_flags, unsigned long flags) } extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); -extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_effective_cpus); +extern int task_can_attach(struct task_struct *p); extern int dl_bw_alloc(int cpu, u64 dl_bw); extern void dl_bw_free(int cpu, u64 dl_bw); #ifdef CONFIG_SMP diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 6587df42cb61..d1073603c96c 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -198,6 +198,8 @@ struct cpuset { * know when to rebuild associated root domain bandwidth information. */ int nr_deadline_tasks; + int nr_migrate_dl_tasks; + u64 sum_migrate_dl_bw; /* Invalid partition error code, not lock protected */ enum prs_errcode prs_err; @@ -2494,16 +2496,23 @@ static int cpuset_can_attach_check(struct cpuset *cs) return 0; } +static void reset_migrate_dl_data(struct cpuset *cs) +{ + cs->nr_migrate_dl_tasks = 0; + cs->sum_migrate_dl_bw = 0; +} + /* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */ static int cpuset_can_attach(struct cgroup_taskset *tset) { struct cgroup_subsys_state *css; - struct cpuset *cs; + struct cpuset *cs, *oldcs; struct task_struct *task; int ret; /* used later by cpuset_attach() */ cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset, &css)); + oldcs = cpuset_attach_old_cs; cs = css_cs(css); mutex_lock(&cpuset_mutex); @@ -2514,7 +2523,7 @@ static int cpuset_can_attach(struct cgroup_taskset *tset) goto out_unlock; cgroup_taskset_for_each(task, css, tset) { - ret = task_can_attach(task, cs->effective_cpus); + ret = task_can_attach(task); if (ret) goto out_unlock; ret = security_task_setscheduler(task); @@ -2522,11 +2531,31 @@ static int cpuset_can_attach(struct cgroup_taskset *tset) goto out_unlock; if (dl_task(task)) { - cs->nr_deadline_tasks++; - cpuset_attach_old_cs->nr_deadline_tasks--; + cs->nr_migrate_dl_tasks++; + cs->sum_migrate_dl_bw += task->dl.dl_bw; } } + if (!cs->nr_migrate_dl_tasks) + goto out_success; + + if (!cpumask_intersects(oldcs->effective_cpus, cs->effective_cpus)) { + int cpu = cpumask_any_and(cpu_active_mask, cs->effective_cpus); + + if (unlikely(cpu >= nr_cpu_ids)) { + reset_migrate_dl_data(cs); + ret = -EINVAL; + goto out_unlock; + } + + ret = dl_bw_alloc(cpu, cs->sum_migrate_dl_bw); + if (ret) { + reset_migrate_dl_data(cs); + goto out_unlock; + } + } + +out_success: /* * Mark attach is in progress. This makes validate_change() fail * changes which zero cpus/mems_allowed. @@ -2549,6 +2578,14 @@ static void cpuset_cancel_attach(struct cgroup_taskset *tset) cs->attach_in_progress--; if (!cs->attach_in_progress) wake_up(&cpuset_attach_wq); + + if (cs->nr_migrate_dl_tasks) { + int cpu = cpumask_any(cs->effective_cpus); + + dl_bw_free(cpu, cs->sum_migrate_dl_bw); + reset_migrate_dl_data(cs); + } + mutex_unlock(&cpuset_mutex); } @@ -2649,6 +2686,12 @@ static void cpuset_attach(struct cgroup_taskset *tset) out: cs->old_mems_allowed = cpuset_attach_nodemask_to; + if (cs->nr_migrate_dl_tasks) { + cs->nr_deadline_tasks += cs->nr_migrate_dl_tasks; + oldcs->nr_deadline_tasks -= cs->nr_migrate_dl_tasks; + reset_migrate_dl_data(cs); + } + cs->attach_in_progress--; if (!cs->attach_in_progress) wake_up(&cpuset_attach_wq); @@ -3328,7 +3371,7 @@ static int cpuset_can_fork(struct task_struct *task, struct css_set *cset) if (ret) goto out_unlock; - ret = task_can_attach(task, cs->effective_cpus); + ret = task_can_attach(task); if (ret) goto out_unlock; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index df659892d7d5..ed0d7381b2ec 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -9294,8 +9294,7 @@ int cpuset_cpumask_can_shrink(const struct cpumask *cur, return ret; } -int task_can_attach(struct task_struct *p, - const struct cpumask *cs_effective_cpus) +int task_can_attach(struct task_struct *p) { int ret = 0; @@ -9308,21 +9307,9 @@ int task_can_attach(struct task_struct *p, * success of set_cpus_allowed_ptr() on all attached tasks * before cpus_mask may be changed. */ - if (p->flags & PF_NO_SETAFFINITY) { + if (p->flags & PF_NO_SETAFFINITY) ret = -EINVAL; - goto out; - } - - if (dl_task(p) && !cpumask_intersects(task_rq(p)->rd->span, - cs_effective_cpus)) { - int cpu = cpumask_any_and(cpu_active_mask, cs_effective_cpus); - if (unlikely(cpu >= nr_cpu_ids)) - return -EINVAL; - ret = dl_bw_alloc(cpu, p->dl.dl_bw); - } - -out: return ret; } -- 2.40.1