From patchwork Mon Jun 12 09:07:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 13275998 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 CDD69C7EE25 for ; Mon, 12 Jun 2023 09:55:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229476AbjFLJzS (ORCPT ); Mon, 12 Jun 2023 05:55:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229697AbjFLJyV (ORCPT ); Mon, 12 Jun 2023 05:54:21 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A47B4C0E; Mon, 12 Jun 2023 02:38:57 -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=MG7QpnmCwLygWJ81Mn2iabAPA0zngwNBxpS2UJOPCco=; b=PgmXbkmwG9TYpDGdocx+LtR6tM l370b2N9nNxi1RmPWxCNObTJ4Voj6TnwUaEMamYzTJY6EkmNWG1KMSqPUKs7IW+4Maipk3vvMjEFR ZaMxjhNAcQQyGWTARi2LdpPcjAIDpMadcwYBjkd27vA7PC1Va2aKU7sfH8xVuq7SvVINulgGTJ51x XjR8xr7yUJ3LF2wwQJd4xe6tOSQnyO6M7lQz1xek40kDnSUJiKz9biq82Fj0QVkT0KEsORIAJNpYr dGHAHUGeUs4DbodpgoR1h3ajXFzvYjku3P4L5rQcre7lw9MZ79S1OiErMltwKmghwzvlIgQByVkHx pDKs2gjQ==; 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 1q8e0g-002N99-Aw; Mon, 12 Jun 2023 09:38:50 +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 E71BC303196; Mon, 12 Jun 2023 11:38:48 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 46BE630A77B54; Mon, 12 Jun 2023 11:38:48 +0200 (CEST) Message-ID: <20230612093538.465891562@infradead.org> User-Agent: quilt/0.66 Date: Mon, 12 Jun 2023 11:07:27 +0200 From: Peter Zijlstra To: torvalds@linux-foundation.org, keescook@chromium.org, gregkh@linuxfoundation.org, pbonzini@redhat.com Cc: masahiroy@kernel.org, nathan@kernel.org, ndesaulniers@google.com, nicolas@fjasle.eu, catalin.marinas@arm.com, will@kernel.org, vkoul@kernel.org, trix@redhat.com, ojeda@kernel.org, peterz@infradead.org, mingo@redhat.com, longman@redhat.com, boqun.feng@gmail.com, dennis@kernel.org, tj@kernel.org, cl@linux.com, acme@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org, irogers@google.com, adrian.hunter@intel.com, 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, paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com, joel@joelfernandes.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, rientjes@google.com, vbabka@suse.cz, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, apw@canonical.com, joe@perches.com, dwaipayanray1@gmail.com, lukas.bulwahn@gmail.com, john.johansen@canonical.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, llvm@lists.linux.dev, linux-perf-users@vger.kernel.org, rcu@vger.kernel.org, linux-security-module@vger.kernel.org, tglx@linutronix.de, ravi.bangoria@amd.com, error27@gmail.com, luc.vanoostenryck@gmail.com Subject: [PATCH v3 14/57] sched: Simplify set_user_nice() References: <20230612090713.652690195@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/core.c | 13 ++++++------- kernel/sched/sched.h | 5 +++++ 2 files changed, 11 insertions(+), 7 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7119,9 +7119,8 @@ static inline int rt_effective_prio(stru void set_user_nice(struct task_struct *p, long nice) { bool queued, running; - int old_prio; - struct rq_flags rf; struct rq *rq; + int old_prio; if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE) return; @@ -7129,7 +7128,9 @@ void set_user_nice(struct task_struct *p * We have to be careful, if called from sys_setpriority(), * the task might be in the middle of scheduling on another CPU. */ - rq = task_rq_lock(p, &rf); + CLASS(task_rq_lock, rq_guard)(p); + rq = rq_guard.rq; + update_rq_clock(rq); /* @@ -7140,8 +7141,9 @@ void set_user_nice(struct task_struct *p */ if (task_has_dl_policy(p) || task_has_rt_policy(p)) { p->static_prio = NICE_TO_PRIO(nice); - goto out_unlock; + return; } + queued = task_on_rq_queued(p); running = task_current(rq, p); if (queued) @@ -7164,9 +7166,6 @@ void set_user_nice(struct task_struct *p * lowered its priority, then reschedule its CPU: */ p->sched_class->prio_changed(rq, p, old_prio); - -out_unlock: - task_rq_unlock(rq, p, &rf); } EXPORT_SYMBOL(set_user_nice); --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1630,6 +1630,11 @@ task_rq_unlock(struct rq *rq, struct tas raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); } +DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, + _T->rq = task_rq_lock(_T->lock, &_T->rf), + task_rq_unlock(_T->rq, _T->lock, &_T->rf), + struct rq *rq; struct rq_flags rf) + static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) __acquires(rq->lock)