From nobody Mon Feb 9 01:46:23 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 BA30CC001DE for ; Wed, 9 Aug 2023 20:43:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234732AbjHIUnz (ORCPT ); Wed, 9 Aug 2023 16:43:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234476AbjHIUnr (ORCPT ); Wed, 9 Aug 2023 16:43:47 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 61B0E100 for ; Wed, 9 Aug 2023 13:43:47 -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=8IwM37e642EshGkaM591nsICKeU24b96IU4dYucK72I=; b=kDEI41ex5Qh1PMu+3DWS1pMzNz Rv/FhSgsDqJmwVpzh91ZxD+ZHqMLjogyP4nUNOaqVK0JHb7V37r6yi8buTfyryfZXc01wbWpRWjnX Fz4qvaigovDAa9B1tInSSU1K9kYgwuYSxDUrDvM+JQ+ERiEM8gzDaUMdRv8lBFbKqxZA+NQRt34di 7j/S0xrZIaqtb2CVchdhrg+4NPxNVju4LGDdurNwebasCDohKc5rKzaryYfwfzDt5626MefDu/ODo 8/Z1uUS/a+9EfVCihNOCQoGHw4pGO7vkD6UD95jEM4lw0k7hQjQBbwc5h17fXKGK81IMac2SFSBdY YV75oCrA==; 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 1qTq1n-008LN8-Cb; Wed, 09 Aug 2023 20:43:35 +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 1411630058D; Wed, 9 Aug 2023 22:43:34 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 5E715206EC339; Wed, 9 Aug 2023 22:43:33 +0200 (CEST) Message-ID: <20230809204200.378325194@infradead.org> User-Agent: quilt/0.66 Date: Wed, 09 Aug 2023 22:24:45 +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 5/8] sched: Simplify sched_rr_get_interval() References: <20230809202440.012625269@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/core.c | 40 ++++++++++++++++------------------------ 1 file changed, 16 insertions(+), 24 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8941,38 +8941,30 @@ SYSCALL_DEFINE1(sched_get_priority_min, =20 static int sched_rr_get_interval(pid_t pid, struct timespec64 *t) { - struct task_struct *p; - unsigned int time_slice; - struct rq_flags rf; - struct rq *rq; + unsigned int time_slice =3D 0; int retval; =20 if (pid < 0) return -EINVAL; =20 - retval =3D -ESRCH; - rcu_read_lock(); - p =3D find_process_by_pid(pid); - if (!p) - goto out_unlock; - - retval =3D security_task_getscheduler(p); - if (retval) - goto out_unlock; - - rq =3D task_rq_lock(p, &rf); - time_slice =3D 0; - if (p->sched_class->get_rr_interval) - time_slice =3D p->sched_class->get_rr_interval(rq, p); - task_rq_unlock(rq, p, &rf); + scoped_guard (rcu) { + struct task_struct *p =3D find_process_by_pid(pid); + if (!p) + return -ESRCH; + + retval =3D security_task_getscheduler(p); + if (retval) + return retval; + + scoped_guard (task_rq_lock, p) { + struct rq *rq =3D scope.rq; + if (p->sched_class->get_rr_interval) + time_slice =3D p->sched_class->get_rr_interval(rq, p); + } + } =20 - rcu_read_unlock(); jiffies_to_timespec64(time_slice, t); return 0; - -out_unlock: - rcu_read_unlock(); - return retval; } =20 /**