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 87187C32772 for ; Fri, 19 Aug 2022 16:38:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353195AbiHSQiY (ORCPT ); Fri, 19 Aug 2022 12:38:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52040 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353593AbiHSQgc (ORCPT ); Fri, 19 Aug 2022 12:36:32 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8BE71230BC; Fri, 19 Aug 2022 09:07:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4E4B7B82816; Fri, 19 Aug 2022 16:07:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 977C0C433C1; Fri, 19 Aug 2022 16:07:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660925243; bh=1nK8ZEsp66fPcxrMcCwgO8x+4qYaTVJvobrwhjo0BWo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fPV/2tkAWzjEurGYiN0koplzHF5hRqqTVwrg8WGf/o8eRLB3F6R/6AalOVJ6Q7X6P 53ng6FNz+UhAi9AxW2KCDa13H/vb3Wiam7SRIzvOWwdoeAzgvTsUTaSKHNvKD+RXmu 7RvcyTjHdEEY0sjXHiksltSk4rmfZz8KtPvOdHUU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dietmar Eggemann , "Peter Zijlstra (Intel)" , Juri Lelli , Sasha Levin Subject: [PATCH 5.10 429/545] sched/deadline: Merge dl_task_can_attach() and dl_cpu_busy() Date: Fri, 19 Aug 2022 17:43:19 +0200 Message-Id: <20220819153848.601645403@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220819153829.135562864@linuxfoundation.org> References: <20220819153829.135562864@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dietmar Eggemann [ Upstream commit 772b6539fdda31462cc08368e78df60b31a58bab ] Both functions are doing almost the same, that is checking if admission control is still respected. With exclusive cpusets, dl_task_can_attach() checks if the destination cpuset (i.e. its root domain) has enough CPU capacity to accommodate the task. dl_cpu_busy() checks if there is enough CPU capacity in the cpuset in case the CPU is hot-plugged out. dl_task_can_attach() is used to check if a task can be admitted while dl_cpu_busy() is used to check if a CPU can be hotplugged out. Make dl_cpu_busy() able to deal with a task and use it instead of dl_task_can_attach() in task_can_attach(). Signed-off-by: Dietmar Eggemann Signed-off-by: Peter Zijlstra (Intel) Acked-by: Juri Lelli Link: https://lore.kernel.org/r/20220302183433.333029-4-dietmar.eggemann@arm.com Signed-off-by: Sasha Levin --- kernel/sched/core.c | 13 +++++++---- kernel/sched/deadline.c | 52 +++++++++++------------------------------ kernel/sched/sched.h | 3 +-- 3 files changed, 24 insertions(+), 44 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index e437d946b27b..042efabf5378 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6605,8 +6605,11 @@ int task_can_attach(struct task_struct *p, } if (dl_task(p) && !cpumask_intersects(task_rq(p)->rd->span, - cs_cpus_allowed)) - ret = dl_task_can_attach(p, cs_cpus_allowed); + cs_cpus_allowed)) { + int cpu = cpumask_any_and(cpu_active_mask, cs_cpus_allowed); + + ret = dl_cpu_busy(cpu, p); + } out: return ret; @@ -6865,8 +6868,10 @@ static void cpuset_cpu_active(void) static int cpuset_cpu_inactive(unsigned int cpu) { if (!cpuhp_tasks_frozen) { - if (dl_cpu_busy(cpu)) - return -EBUSY; + int ret = dl_cpu_busy(cpu, NULL); + + if (ret) + return ret; cpuset_update_active_cpus(); } else { num_cpus_frozen++; diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 933706106b98..aaf98771f935 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -2825,41 +2825,6 @@ bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr) } #ifdef CONFIG_SMP -int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed) -{ - unsigned long flags, cap; - unsigned int dest_cpu; - struct dl_bw *dl_b; - bool overflow; - int ret; - - dest_cpu = cpumask_any_and(cpu_active_mask, cs_cpus_allowed); - - rcu_read_lock_sched(); - dl_b = dl_bw_of(dest_cpu); - raw_spin_lock_irqsave(&dl_b->lock, flags); - cap = dl_bw_capacity(dest_cpu); - overflow = __dl_overflow(dl_b, cap, 0, p->dl.dl_bw); - if (overflow) { - ret = -EBUSY; - } else { - /* - * We reserve space for this task in the destination - * root_domain, as we can't fail after this point. - * We will free resources in the source root_domain - * later on (see set_cpus_allowed_dl()). - */ - int cpus = dl_bw_cpus(dest_cpu); - - __dl_add(dl_b, p->dl.dl_bw, cpus); - ret = 0; - } - raw_spin_unlock_irqrestore(&dl_b->lock, flags); - rcu_read_unlock_sched(); - - return ret; -} - int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial) { @@ -2881,7 +2846,7 @@ int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, return ret; } -bool dl_cpu_busy(unsigned int cpu) +int dl_cpu_busy(int cpu, struct task_struct *p) { unsigned long flags, cap; struct dl_bw *dl_b; @@ -2891,11 +2856,22 @@ bool dl_cpu_busy(unsigned int cpu) dl_b = dl_bw_of(cpu); raw_spin_lock_irqsave(&dl_b->lock, flags); cap = dl_bw_capacity(cpu); - overflow = __dl_overflow(dl_b, cap, 0, 0); + overflow = __dl_overflow(dl_b, cap, 0, p ? p->dl.dl_bw : 0); + + if (!overflow && p) { + /* + * We reserve space for this task in the destination + * root_domain, as we can't fail after this point. + * We will free resources in the source root_domain + * later on (see set_cpus_allowed_dl()). + */ + __dl_add(dl_b, p->dl.dl_bw, dl_bw_cpus(cpu)); + } + raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); - return overflow; + return overflow ? -EBUSY : 0; } #endif diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 8d39f5d99172..12c65628801c 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -347,9 +347,8 @@ extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); extern bool __checkparam_dl(const struct sched_attr *attr); extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); -extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); -extern bool dl_cpu_busy(unsigned int cpu); +extern int dl_cpu_busy(int cpu, struct task_struct *p); #ifdef CONFIG_CGROUP_SCHED -- 2.35.1