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 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,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 B9DD0C4743C for ; Wed, 23 Jun 2021 17:41:51 +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 8A3DB60BD3 for ; Wed, 23 Jun 2021 17:41:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8A3DB60BD3 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=M8RgTuKeWL2LSYICrJsOs0q81mSQHRNu1rr1oQ/6R1A=; b=3HOGifrRhLeT9K SEsOhchYDjtYj1mfvFNNeSYfRJfmQ/+QpCB3fkKH6LB+G7E9DKvoJ3uo3JXSYIUxHHCanr2EPU76V VpAoR+VzmAZncWugq1MmVhqaTgAZ/EEF9uayGHsJxzFBDNYzbOCLzpTS2gS22O31PfU4X6UQNzJbg C3kC6SXBSzpzE0EGQW8btwuNgjjLHpYWCZAYPWv+erqr7Rd0m77Sp/UqDNyxvk1Cg5L47UA7zOeIm popLjjZDZONEDgEj5kEvboKCqPdjrl1R73B2pyGWbMLlyeMTH8uI/yrhQS/LpidNtCwSwj6XTTmFI FlTdyogU50HQkmJmmyyg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lw6rN-00BRzT-Eg; Wed, 23 Jun 2021 17:40:21 +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 1lw6qH-00BRUF-Hu for linux-arm-kernel@lists.infradead.org; Wed, 23 Jun 2021 17:39:15 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id A9E2A611CB; Wed, 23 Jun 2021 17:39:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624469953; bh=XvhUI22KCWdadFes3lQB7XTm/HPj63vHhDt+RM3Mht0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L+FaATX7FPwkpd19t2kzVhSKZaYZCECFQbkoqA7VGmKTaauyaWZPqT1ybKZYZzYwO 1xerV01J0gTKb1FvgScoEMw90Oc4egb02PVahHTXtE2EB6wfdFfc/h0l9PXawuRBpD xwjS8AuzoCgmxl7EUqpaUa2X1qxdTUOcMg6c4c40xGS8qfMjrrSTHwMcYix6WwR+Si I+vT6GoPnln56DiADOxmeLU41mQn+Y7RAUxJ/ttHs6uH/XGx4mfEzQt8g5Qt5qf5zb EPy6PFOH2YViXOW9l6e2lI4GVhIGOgT4oCo3/U0jGC8v3ckgSihz6lMfJh+ud/a658 +PllsBLXR1C6g== 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 , Mark Rutland , kernel-team@android.com Subject: [PATCH v10 04/16] cpuset: Cleanup cpuset_cpus_allowed_fallback() use in select_fallback_rq() Date: Wed, 23 Jun 2021 18:38:36 +0100 Message-Id: <20210623173848.318-5-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210623173848.318-1-will@kernel.org> References: <20210623173848.318-1-will@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210623_103913_682602_E6E4B715 X-CRM114-Status: GOOD ( 17.33 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org select_fallback_rq() only needs to recheck for an allowed CPU if the affinity mask of the task has changed since the last check. Return a 'bool' from cpuset_cpus_allowed_fallback() to indicate whether the affinity mask was updated, and use this to elide the allowed check when the mask has been left alone. No functional change. Suggested-by: Valentin Schneider Reviewed-by: Valentin Schneider Signed-off-by: Will Deacon --- include/linux/cpuset.h | 5 +++-- kernel/cgroup/cpuset.c | 10 ++++++++-- kernel/sched/core.c | 3 +-- 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index 414a8e694413..d2b9c41c8edf 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -59,7 +59,7 @@ extern void cpuset_wait_for_hotplug(void); extern void cpuset_read_lock(void); extern void cpuset_read_unlock(void); extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask); -extern void cpuset_cpus_allowed_fallback(struct task_struct *p); +extern bool cpuset_cpus_allowed_fallback(struct task_struct *p); extern nodemask_t cpuset_mems_allowed(struct task_struct *p); #define cpuset_current_mems_allowed (current->mems_allowed) void cpuset_init_current_mems_allowed(void); @@ -188,8 +188,9 @@ static inline void cpuset_cpus_allowed(struct task_struct *p, cpumask_copy(mask, task_cpu_possible_mask(p)); } -static inline void cpuset_cpus_allowed_fallback(struct task_struct *p) +static inline bool cpuset_cpus_allowed_fallback(struct task_struct *p) { + return false; } static inline nodemask_t cpuset_mems_allowed(struct task_struct *p) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 4e7c271e3800..a6bab2259f98 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -3327,17 +3327,22 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) * which will not contain a sane cpumask during cases such as cpu hotplugging. * This is the absolute last resort for the scheduler and it is only used if * _every_ other avenue has been traveled. + * + * Returns true if the affinity of @tsk was changed, false otherwise. **/ -void cpuset_cpus_allowed_fallback(struct task_struct *tsk) +bool cpuset_cpus_allowed_fallback(struct task_struct *tsk) { const struct cpumask *cs_mask; + bool changed = false; const struct cpumask *possible_mask = task_cpu_possible_mask(tsk); rcu_read_lock(); cs_mask = task_cs(tsk)->cpus_allowed; - if (is_in_v2_mode() && cpumask_subset(cs_mask, possible_mask)) + if (is_in_v2_mode() && cpumask_subset(cs_mask, possible_mask)) { do_set_cpus_allowed(tsk, cs_mask); + changed = true; + } rcu_read_unlock(); /* @@ -3357,6 +3362,7 @@ void cpuset_cpus_allowed_fallback(struct task_struct *tsk) * select_fallback_rq() will fix things ups and set cpu_possible_mask * if required. */ + return changed; } void __init cpuset_init_current_mems_allowed(void) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 0c1b6f1a6c91..9e75cb3fbc9c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2779,8 +2779,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p) /* No more Mr. Nice Guy. */ switch (state) { case cpuset: - if (IS_ENABLED(CONFIG_CPUSETS)) { - cpuset_cpus_allowed_fallback(p); + if (cpuset_cpus_allowed_fallback(p)) { state = possible; break; } -- 2.32.0.93.g670b81a890-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel