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[2620:137:e000::1:20]) by mx.google.com with ESMTP id y13-20020a170906524d00b009930c925bd9si8675045ejm.945.2023.08.01.15.31.38; Tue, 01 Aug 2023 15:32:02 -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=desiato.20200630 header.b=CmSlmMvB; 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 S232257AbjHAVZH (ORCPT + 99 others); Tue, 1 Aug 2023 17:25:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44424 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232258AbjHAVYz (ORCPT ); Tue, 1 Aug 2023 17:24:55 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC3D435A2 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=desiato.20200630; 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=drbNuL55DYuL5wiscrlTnGAb/cO6SeGIhgtGTiA6PhQ=; b=CmSlmMvBqFeZkasybngqkB/9/Z mUv7r6cmiKzOML5p3sP/7eNW16u9qXgad8LSgfbpyGh4CxsLLmw2+fNFo/ocTFfJNo0Roo/ELwr6o VWbMNAPshVBVeQplDvk7SN1Lgu5HGT6/O2moDQB/+MlNaKc8mQ0s4GL3cEOphzAOK24BFFOkgWJFk GzKQEzHnF7TRhjXrm0ER9eKzep+vUFLQNNxtbR+DusrIdrO6+z7R6eEDn9IfZESBYjm8ARA9ed+eh 4e2nwM1i8mQ175codWVx83vH1F5D6LSOw/I4VMx1Ei1MK7jL0k6BtcRWfsQ7puqN0FmXoKGXL4Zph igvkYxww==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qQwqn-00EvTv-1f; Tue, 01 Aug 2023 21:24:20 +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 BEDCA3006ED; Tue, 1 Aug 2023 23:24:15 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 4BEB720282F78; Tue, 1 Aug 2023 23:24:15 +0200 (CEST) Message-ID: <20230801211812.168490417@infradead.org> User-Agent: quilt/0.66 Date: Tue, 01 Aug 2023 22:41:27 +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 6/9] sched: Simplify sched_exec() References: <20230801204121.929256934@infradead.org> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, 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: 1773067694968694900 X-GMAIL-MSGID: 1773067694968694900 Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/core.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5431,23 +5431,20 @@ unsigned int nr_iowait(void) void sched_exec(void) { struct task_struct *p = current; - unsigned long flags; + struct migration_arg arg; int dest_cpu; - raw_spin_lock_irqsave(&p->pi_lock, flags); - dest_cpu = p->sched_class->select_task_rq(p, task_cpu(p), WF_EXEC); - if (dest_cpu == smp_processor_id()) - goto unlock; + scoped_guard (raw_spinlock_irqsave, &p->pi_lock) { + dest_cpu = p->sched_class->select_task_rq(p, task_cpu(p), WF_EXEC); + if (dest_cpu == smp_processor_id()) + return; - if (likely(cpu_active(dest_cpu))) { - struct migration_arg arg = { p, dest_cpu }; + if (unlikely(!cpu_active(dest_cpu))) + return; - raw_spin_unlock_irqrestore(&p->pi_lock, flags); - stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); - return; + arg = (struct migration_arg){ p, dest_cpu }; } -unlock: - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); } #endif