From patchwork Wed Jun 2 13:12:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 453912 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 14D03C47096 for ; Wed, 2 Jun 2021 13:31:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F1430613D6 for ; Wed, 2 Jun 2021 13:31:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230102AbhFBNdE (ORCPT ); Wed, 2 Jun 2021 09:33:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229803AbhFBNc4 (ORCPT ); Wed, 2 Jun 2021 09:32:56 -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 CDE52C06175F; Wed, 2 Jun 2021 06:31:12 -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=StHUrZVTyidITaso9MHtdeY9nPrW5Ogz3wqQtaiZ0ws=; b=P6N4rxYRYVyJKXyPv/qWD9zHEM ae7/GsDR0G4z0W3zvLFylIHdZxOruBRKoQnWY8N7W1rLQbprQYlZS9dUYXxQLhu4AjsLFXcwYBtlb eD49gln0vrb9EAWt9nv02V8yo6iI8t6lfBp4ez+3qPHUG9tGWQq/Ui8PnSuXrhM6rnBI0cO7Swj1I 3oXGm9LyYJOi4Ch+3FlALr0ysdqMd8mylXs107QW8UAnjvRfZ51B4Hs3PtzRgkCxUTtPW/2AMfCG/ ndwfk+vKAcWWm7HgBB7G3jkOSIw+UMNaGluyVVk4MLNMCyWDacIRZvLv7nz2KpnM+noLcBRHUzGbP FF2fzzTQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1loQxX-002toY-D6; Wed, 02 Jun 2021 13:31:06 +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 (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 3DD6B300301; Wed, 2 Jun 2021 15:31:05 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 989162C14C594; Wed, 2 Jun 2021 15:31:04 +0200 (CEST) Message-ID: <20210602133040.334970485@infradead.org> User-Agent: quilt/0.66 Date: Wed, 02 Jun 2021 15:12:27 +0200 From: Peter Zijlstra To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira Cc: Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Jens Axboe , Alasdair Kergon , Mike Snitzer , dm-devel@redhat.com, "David S. Miller" , Jakub Kicinski , Felipe Balbi , Greg Kroah-Hartman , Alexander Viro , Tejun Heo , Zefan Li , Johannes Weiner , Jason Wessel , Daniel Thompson , Douglas Anderson , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , "Rafael J. Wysocki" , Pavel Machek , Will Deacon , Waiman Long , Boqun Feng , Oleg Nesterov , Davidlohr Bueso , "Paul E. McKenney" , Josh Triplett , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , John Stultz , Stephen Boyd , Andrew Morton , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, linux-perf-users@vger.kernel.org, linux-pm@vger.kernel.org, rcu@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org Subject: [PATCH 2/6] sched: Introduce task_is_running() References: <20210602131225.336600299@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Replace a bunch of 'p->state == TASK_RUNNING' with a new helper: task_is_running(p). Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/kernel/process.c | 4 ++-- block/blk-mq.c | 2 +- include/linux/sched.h | 2 ++ kernel/locking/lockdep.c | 2 +- kernel/rcu/tree_plugin.h | 2 +- kernel/sched/core.c | 6 +++--- kernel/sched/stats.h | 2 +- kernel/signal.c | 2 +- kernel/softirq.c | 3 +-- mm/compaction.c | 2 +- 10 files changed, 14 insertions(+), 13 deletions(-) --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -931,7 +931,7 @@ unsigned long get_wchan(struct task_stru unsigned long start, bottom, top, sp, fp, ip, ret = 0; int count = 0; - if (p == current || p->state == TASK_RUNNING) + if (p == current || task_is_running(p)) return 0; if (!try_get_task_stack(p)) @@ -975,7 +975,7 @@ unsigned long get_wchan(struct task_stru goto out; } fp = READ_ONCE_NOCHECK(*(unsigned long *)fp); - } while (count++ < 16 && p->state != TASK_RUNNING); + } while (count++ < 16 && !task_is_running(p)); out: put_task_stack(p); --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3926,7 +3926,7 @@ int blk_poll(struct request_queue *q, bl if (signal_pending_state(state, current)) __set_current_state(TASK_RUNNING); - if (current->state == TASK_RUNNING) + if (task_is_running(current)) return 1; if (ret < 0 || !spin) break; --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -113,6 +113,8 @@ struct task_group; __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ TASK_PARKED) +#define task_is_running(task) (READ_ONCE((task)->state) == TASK_RUNNING) + #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -760,7 +760,7 @@ static void lockdep_print_held_locks(str * It's not reliable to print a task's held locks if it's not sleeping * and it's not the current task. */ - if (p->state == TASK_RUNNING && p != current) + if (p != current && task_is_running(p)) return; for (i = 0; i < depth; i++) { printk(" #%d: ", i); --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2768,7 +2768,7 @@ EXPORT_SYMBOL_GPL(rcu_bind_current_to_no #ifdef CONFIG_SMP static char *show_rcu_should_be_on_cpu(struct task_struct *tsp) { - return tsp && tsp->state == TASK_RUNNING && !tsp->on_cpu ? "!" : ""; + return tsp && task_is_running(tsp) && !tsp->on_cpu ? "!" : ""; } #else // #ifdef CONFIG_SMP static char *show_rcu_should_be_on_cpu(struct task_struct *tsp) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5989,7 +5989,7 @@ static inline void sched_submit_work(str { unsigned int task_flags; - if (!tsk->state) + if (task_is_running(tsk)) return; task_flags = tsk->flags; @@ -7964,7 +7964,7 @@ int __sched yield_to(struct task_struct if (curr->sched_class != p->sched_class) goto out_unlock; - if (task_running(p_rq, p) || p->state) + if (task_running(p_rq, p) || !task_is_running(p)) goto out_unlock; yielded = curr->sched_class->yield_to_task(rq, p); @@ -8167,7 +8167,7 @@ void sched_show_task(struct task_struct pr_info("task:%-15.15s state:%c", p->comm, task_state_to_char(p)); - if (p->state == TASK_RUNNING) + if (task_is_running(p)) pr_cont(" running task "); #ifdef CONFIG_DEBUG_STACK_USAGE free = stack_not_used(p); --- a/kernel/sched/stats.h +++ b/kernel/sched/stats.h @@ -217,7 +217,7 @@ static inline void sched_info_depart(str rq_sched_info_depart(rq, delta); - if (t->state == TASK_RUNNING) + if (task_is_running(t)) sched_info_enqueue(rq, t); } --- a/kernel/signal.c +++ b/kernel/signal.c @@ -4719,7 +4719,7 @@ void kdb_send_sig(struct task_struct *t, } new_t = kdb_prev_t != t; kdb_prev_t = t; - if (t->state != TASK_RUNNING && new_t) { + if (!task_is_running(t) && new_t) { spin_unlock(&t->sighand->siglock); kdb_printf("Process is not RUNNING, sending a signal from " "kdb risks deadlock\n" --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -92,8 +92,7 @@ static bool ksoftirqd_running(unsigned l if (pending & SOFTIRQ_NOW_MASK) return false; - return tsk && (tsk->state == TASK_RUNNING) && - !__kthread_should_park(tsk); + return tsk && task_is_running(tsk) && !__kthread_should_park(tsk); } #ifdef CONFIG_TRACE_IRQFLAGS --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1955,7 +1955,7 @@ static inline bool is_via_compact_memory static bool kswapd_is_running(pg_data_t *pgdat) { - return pgdat->kswapd && (pgdat->kswapd->state == TASK_RUNNING); + return pgdat->kswapd && task_is_running(pgdat->kswapd); } /*