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[2620:137:e000::1:20]) by mx.google.com with ESMTP id m21-20020a1709066d1500b009930e13beb8si117963ejr.952.2023.08.01.14.46.21; Tue, 01 Aug 2023 14:46:45 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=OBxsTC6y; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230162AbjHAVZB (ORCPT + 99 others); Tue, 1 Aug 2023 17:25:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232257AbjHAVYz (ORCPT ); Tue, 1 Aug 2023 17:24:55 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3BE035A4 for ; Tue, 1 Aug 2023 14:24:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=tN5fF7Wyh35qBJFCdjEuKMaMwIiqau8XmW0j2x/SMjk=; b=OBxsTC6ytcWiY/yE6bTaLRGenU UXNPiXEek3EpXmglUInzCpiKgnS3Xz9uHEbo7oY5WDfMfRjUz6q3DK9ojN+5Su+zHJowi8JZkdBJ8 rZtpQZszObYqufmw4gEPMk5APgE2bWfFNTlvKj10VcO2RwkEUplUW2a7aLx0tk2rTvhA1MBl95JeA MLf1QC02VFnIlh00Zr9IL404fYayP1cF/EJqh1gO6LAcLlbPHhXEWK/jbPzOwChgZjJR1QxrVvTp9 Ss9CbChT2TfWVE/c/meuiPSnO7OW5RaPYlArIXzJru3Hk79gP0WwXf/+mZQHrSIM7limw+vBxut7M /lGBWahg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1qQwqn-00B5yk-GZ; Tue, 01 Aug 2023 21:24:17 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id BEE9330334C; Tue, 1 Aug 2023 23:24:15 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 5B5942026B3DC; Tue, 1 Aug 2023 23:24:15 +0200 (CEST) Message-ID: <20230801211812.371787909@infradead.org> User-Agent: quilt/0.66 Date: Tue, 01 Aug 2023 22:41:30 +0200 From: Peter Zijlstra To: mingo@redhat.com Cc: peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org Subject: [PATCH 9/9] sched: Simplify sched_core_cpu_{starting,deactivate}() References: <20230801204121.929256934@infradead.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1773064846516016790 X-GMAIL-MSGID: 1773064846516016790 Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/core.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6331,20 +6331,24 @@ static void queue_core_balance(struct rq queue_balance_callback(rq, &per_cpu(core_balance_head, rq->cpu), sched_core_balance); } +DEFINE_LOCK_GUARD_1(core_lock, int, + sched_core_lock(*_T->lock, &_T->flags), + sched_core_unlock(*_T->lock, &_T->flags), + unsigned long flags) + static void sched_core_cpu_starting(unsigned int cpu) { const struct cpumask *smt_mask = cpu_smt_mask(cpu); struct rq *rq = cpu_rq(cpu), *core_rq = NULL; - unsigned long flags; int t; - sched_core_lock(cpu, &flags); + guard(core_lock)(&cpu); WARN_ON_ONCE(rq->core != rq); /* if we're the first, we'll be our own leader */ if (cpumask_weight(smt_mask) == 1) - goto unlock; + return; /* find the leader */ for_each_cpu(t, smt_mask) { @@ -6358,7 +6362,7 @@ static void sched_core_cpu_starting(unsi } if (WARN_ON_ONCE(!core_rq)) /* whoopsie */ - goto unlock; + return; /* install and validate core_rq */ for_each_cpu(t, smt_mask) { @@ -6369,29 +6373,25 @@ static void sched_core_cpu_starting(unsi WARN_ON_ONCE(rq->core != core_rq); } - -unlock: - sched_core_unlock(cpu, &flags); } static void sched_core_cpu_deactivate(unsigned int cpu) { const struct cpumask *smt_mask = cpu_smt_mask(cpu); struct rq *rq = cpu_rq(cpu), *core_rq = NULL; - unsigned long flags; int t; - sched_core_lock(cpu, &flags); + guard(core_lock)(&cpu); /* if we're the last man standing, nothing to do */ if (cpumask_weight(smt_mask) == 1) { WARN_ON_ONCE(rq->core != rq); - goto unlock; + return; } /* if we're not the leader, nothing to do */ if (rq->core != rq) - goto unlock; + return; /* find a new leader */ for_each_cpu(t, smt_mask) { @@ -6402,7 +6402,7 @@ static void sched_core_cpu_deactivate(un } if (WARN_ON_ONCE(!core_rq)) /* impossible */ - goto unlock; + return; /* copy the shared state to the new leader */ core_rq->core_task_seq = rq->core_task_seq; @@ -6424,9 +6424,6 @@ static void sched_core_cpu_deactivate(un rq = cpu_rq(t); rq->core = core_rq; } - -unlock: - sched_core_unlock(cpu, &flags); } static inline void sched_core_cpu_dying(unsigned int cpu)