From patchwork Wed Jun 2 16:47:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 12295369 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=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 6C69EC47083 for ; Wed, 2 Jun 2021 16:55:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 356FD61C49 for ; Wed, 2 Jun 2021 16:55:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 356FD61C49 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=nS/8qk9wPyZfWcJxnQXtALRI3P4NxWIUCZrH/8NTqfA=; b=YTdf1bJe7XctxH KhYz3lpm4q49aT3a3ur20F56FKD7Ba7gOhHP4UjviVOdHGJYGT3W1vI+0EVOg5Tlr08GCPKMLz2HN Ig/+Wod1IBnx1usIezkT2clKu6jvwOvQ6lG9At+8HIgT2X1+TPYjqH3nmrnUK2pBUUWiL62w0BRoA AN9qdGeYheipARgWj8v5o3SxUcCgBhbsf+/Po25TA/lBx5JQqIaZY249q6wQFEaHKRDiEQCUiYi12 yCPyUmd/NgtOCCuGnFkJHIHyufYD/rvV8J1vCQxi3Vgn8HZ0CGCv1CL3NSiZeXAbuVNZOiJpX9CHn 3B94BcHVi4bxC0dKWTPA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1loU7p-005Hvl-Bj; Wed, 02 Jun 2021 16:53:49 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1loU2U-005FMi-Ln for linux-arm-kernel@lists.infradead.org; Wed, 02 Jun 2021 16:48:20 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id E6C1E610A1; Wed, 2 Jun 2021 16:48:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622652498; bh=+0NLguOvQ/SVpTtQ+rBgEHqDg+B1MsugcBVESzqvkUQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qMOwJ5J+c8M3VPygei6ZBu4e8coSkSgxL13UeArKq5lulgQS0KbWjjSd4SedVOhN9 g1wQ0FHZcYU89mWzarAuy74oOIbp3B1aSXmNDiFRsqyyOrgaS9bzxkigTn6j9S2+Wd n3q2SKSYH48NK8G8tHY/5InbrZQurzJVJWJzXHI8gN3z+VG/FANIseCvKrTTR3JEFA uAwe9fwzlJXCt/4ZvvhWIC6JMB7//5r/58IBwzIyHy5H3z9l5eVPJLxBFIFJPeJrEQ YQ3NZf2eWXwVtfKC2IainGSXiRo3ifGYP1sDbirsoc8AJ7PmnU8oVkJMM0L3SiT20+ HUIk+2/RLtqhQ== From: Will Deacon To: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , Marc Zyngier , Greg Kroah-Hartman , Peter Zijlstra , Morten Rasmussen , Qais Yousef , Suren Baghdasaryan , Quentin Perret , Tejun Heo , Johannes Weiner , Ingo Molnar , Juri Lelli , Vincent Guittot , "Rafael J. Wysocki" , Dietmar Eggemann , Daniel Bristot de Oliveira , Valentin Schneider , kernel-team@android.com Subject: [PATCH v8 12/19] sched: Introduce task_cpus_dl_admissible() to check proposed affinity Date: Wed, 2 Jun 2021 17:47:12 +0100 Message-Id: <20210602164719.31777-13-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210602164719.31777-1-will@kernel.org> References: <20210602164719.31777-1-will@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210602_094818_786282_A19CA570 X-CRM114-Status: GOOD ( 15.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In preparation for restricting the affinity of a task during execve() on arm64, introduce a new task_cpus_dl_admissible() helper function to give an indication as to whether the restricted mask is admissible for a deadline task. Signed-off-by: Will Deacon Reviewed-by: Daniel Bristot de Oliveira --- include/linux/sched.h | 6 ++++++ kernel/sched/core.c | 44 +++++++++++++++++++++++++++---------------- 2 files changed, 34 insertions(+), 16 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 91a6cfeae242..9b17d8cfa6ef 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1691,6 +1691,7 @@ extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); extern void release_user_cpus_ptr(struct task_struct *p); +extern bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask); extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); #else @@ -1713,6 +1714,11 @@ static inline void release_user_cpus_ptr(struct task_struct *p) { WARN_ON(p->user_cpus_ptr); } + +static inline bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) +{ + return true; +} #endif extern int yield_to(struct task_struct *p, bool preempt); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 58e2cf7520c0..b4f8dc18ae11 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6933,6 +6933,31 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, return retval; } +#ifdef CONFIG_SMP +bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) +{ + bool ret; + + /* + * If the task isn't a deadline task or admission control is + * disabled then we don't care about affinity changes. + */ + if (!task_has_dl_policy(p) || !dl_bandwidth_enabled()) + return true; + + /* + * Since bandwidth control happens on root_domain basis, + * if admission test is enabled, we only admit -deadline + * tasks allowed to run on all the CPUs in the task's + * root_domain. + */ + rcu_read_lock(); + ret = cpumask_subset(task_rq(p)->rd->span, mask); + rcu_read_unlock(); + return ret; +} +#endif + static int __sched_setaffinity(struct task_struct *p, const struct cpumask *mask) { @@ -6950,23 +6975,10 @@ __sched_setaffinity(struct task_struct *p, const struct cpumask *mask) cpuset_cpus_allowed(p, cpus_allowed); cpumask_and(new_mask, mask, cpus_allowed); - /* - * Since bandwidth control happens on root_domain basis, - * if admission test is enabled, we only admit -deadline - * tasks allowed to run on all the CPUs in the task's - * root_domain. - */ -#ifdef CONFIG_SMP - if (task_has_dl_policy(p) && dl_bandwidth_enabled()) { - rcu_read_lock(); - if (!cpumask_subset(task_rq(p)->rd->span, new_mask)) { - retval = -EBUSY; - rcu_read_unlock(); - goto out_free_new_mask; - } - rcu_read_unlock(); + if (!task_cpus_dl_admissible(p, new_mask)) { + retval = -EBUSY; + goto out_free_new_mask; } -#endif again: retval = __set_cpus_allowed_ptr(p, new_mask, SCA_CHECK | SCA_USER); if (retval)