From nobody Tue Jun 23 08:15:27 2026 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 73471C433EF for ; Tue, 8 Mar 2022 22:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350751AbiCHW0c (ORCPT ); Tue, 8 Mar 2022 17:26:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236364AbiCHW0W (ORCPT ); Tue, 8 Mar 2022 17:26:22 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2E14583B8; Tue, 8 Mar 2022 14:25:24 -0800 (PST) Date: Tue, 08 Mar 2022 22:25:22 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1646778323; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2QB/pjbswHVZkoslsBgW+33JDvfUolZDAradLFmM+WE=; b=FUk+Unsgm6yMlTn4npOufVbejd76OW4xZxU4uBZUtbv+Mnc1PNs9t3f/X81MFiElYidqA2 anlyGagMKAASDHeSSb4+1ZUdjdAJfiWLcLq6DNkZqdimWgrQjBYnCyMgwwavTbej6dW+og 4bW/lI00GpngshnOGQnOA6qf0CqkQ/UaR+hg3j3E/KOtH1C64A13Cl1AiBcgKvEbwv15Ao xwb/RikRY8SNQgjohYYP9rNctzaGRyqiHfSdeY+6h/iCIlXj/jQkQfx5AbvSdBSvqenyNN xYD93XkJ5RWn4IozJ4RLOjrz4QoqyTwzOfJ7H4vDtuu1tBmQIiZ6Xs7pvU78ng== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1646778323; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2QB/pjbswHVZkoslsBgW+33JDvfUolZDAradLFmM+WE=; b=F5btkqwLMAFYwT4t5gmalcMCm3E6DVf2G3U1BvJKpQ/gYi/Cog+A4lSeWZ+MPY3fr/ub7b hAQQVCg61gS3SlBw== From: "tip-bot2 for Dietmar Eggemann" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/deadline: Merge dl_task_can_attach() and dl_cpu_busy() Cc: Dietmar Eggemann , "Peter Zijlstra (Intel)" , Juri Lelli , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20220302183433.333029-4-dietmar.eggemann@arm.com> References: <20220302183433.333029-4-dietmar.eggemann@arm.com> MIME-Version: 1.0 Message-ID: <164677832223.16921.15292131794875687369.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 772b6539fdda31462cc08368e78df60b31a58bab Gitweb: https://git.kernel.org/tip/772b6539fdda31462cc08368e78df60b3= 1a58bab Author: Dietmar Eggemann AuthorDate: Wed, 02 Mar 2022 19:34:30 +01:00 Committer: Peter Zijlstra CommitterDate: Tue, 08 Mar 2022 16:08:39 +01:00 sched/deadline: Merge dl_task_can_attach() and dl_cpu_busy() 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@ar= m.com --- 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 d342c4c..68736d1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8805,8 +8805,11 @@ int task_can_attach(struct task_struct *p, } =20 if (dl_task(p) && !cpumask_intersects(task_rq(p)->rd->span, - cs_cpus_allowed)) - ret =3D dl_task_can_attach(p, cs_cpus_allowed); + cs_cpus_allowed)) { + int cpu =3D cpumask_any_and(cpu_active_mask, cs_cpus_allowed); + + ret =3D dl_cpu_busy(cpu, p); + } =20 out: return ret; @@ -9090,8 +9093,10 @@ 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 =3D 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 81bf976..de677b1 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -2992,41 +2992,6 @@ bool dl_param_changed(struct task_struct *p, const s= truct sched_attr *attr) } =20 #ifdef CONFIG_SMP -int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpu= s_allowed) -{ - unsigned long flags, cap; - unsigned int dest_cpu; - struct dl_bw *dl_b; - bool overflow; - int ret; - - dest_cpu =3D cpumask_any_and(cpu_active_mask, cs_cpus_allowed); - - rcu_read_lock_sched(); - dl_b =3D dl_bw_of(dest_cpu); - raw_spin_lock_irqsave(&dl_b->lock, flags); - cap =3D dl_bw_capacity(dest_cpu); - overflow =3D __dl_overflow(dl_b, cap, 0, p->dl.dl_bw); - if (overflow) { - ret =3D -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 =3D dl_bw_cpus(dest_cpu); - - __dl_add(dl_b, p->dl.dl_bw, cpus); - ret =3D 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) { @@ -3048,7 +3013,7 @@ int dl_cpuset_cpumask_can_shrink(const struct cpumask= *cur, return ret; } =20 -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; @@ -3058,11 +3023,22 @@ bool dl_cpu_busy(unsigned int cpu) dl_b =3D dl_bw_of(cpu); raw_spin_lock_irqsave(&dl_b->lock, flags); cap =3D dl_bw_capacity(cpu); - overflow =3D __dl_overflow(dl_b, cap, 0, 0); + overflow =3D __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(); =20 - return overflow; + return overflow ? -EBUSY : 0; } #endif =20 diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 4dfc3b0..0720cf0 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -324,9 +324,8 @@ 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_att= r *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); =20 #ifdef CONFIG_CGROUP_SCHED