From patchwork Wed Jun 2 13:12:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 12294365 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 58E8CC47083 for ; Wed, 2 Jun 2021 13:33:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 39CEF60BD3 for ; Wed, 2 Jun 2021 13:33:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229801AbhFBNfW (ORCPT ); Wed, 2 Jun 2021 09:35:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230138AbhFBNfM (ORCPT ); Wed, 2 Jun 2021 09:35:12 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3CF39C06174A; Wed, 2 Jun 2021 06:33:29 -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=Sj4Xan1+3aJ6Po5iAXxX9E8AwNGjzz5eYxQ6hRhen0g=; b=hMlj520jMnvNI6O5tUqcyzOgHW EHiJoaUSJQ6hVJ7Wpebgbxf98jjwH5xRoh67t9mLVd2A/HfLxY2Yx4h5lqvgKDYtgGojEvu4IefSN 3DS6NOM57KiQOuJ7YRpVuKxZsMsiHqnRArRHs23pjdvHMQBl6lq9QREaZLgYa75oH3MWB+gJ1tC1J +wH4gCxswnyNBmjCumjXo1vOZE8FBxAebh/yrQhXJi8Y54MOt/nDCRBdOX3lrbMZSfd4Wjc7Ev0IX oIeI/gLN/0oqtU5QOuXfbcGteiSWIxBhDz2ucFEF9xi8LFZyzr9Fj0M1df6hbsxkqYJsywFl4l0AK rwAquI9Q==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1loQxh-00B8o4-IG; Wed, 02 Jun 2021 13:31:12 +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 492F93004DE; Wed, 2 Jun 2021 15:31:05 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 9ED912C189403; Wed, 2 Jun 2021 15:31:04 +0200 (CEST) Message-ID: <20210602133040.461908001@infradead.org> User-Agent: quilt/0.66 Date: Wed, 02 Jun 2021 15:12:29 +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 4/6] sched: Add get_current_state() References: <20210602131225.336600299@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Remove yet another few p->state accesses. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Will Deacon --- block/blk-mq.c | 2 +- include/linux/sched.h | 2 ++ kernel/freezer.c | 2 +- kernel/sched/core.c | 6 +++--- 4 files changed, 7 insertions(+), 5 deletions(-) --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3891,7 +3891,7 @@ int blk_poll(struct request_queue *q, bl hctx->poll_considered++; - state = current->state; + state = get_current_state(); do { int ret; --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -212,6 +212,8 @@ struct task_group; #endif +#define get_current_state() READ_ONCE(current->state) + /* Task command name length: */ #define TASK_COMM_LEN 16 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -58,7 +58,7 @@ bool __refrigerator(bool check_kthr_stop /* Hmm, should we be allowed to suspend when there are realtime processes around? */ bool was_frozen = false; - long save = current->state; + unsigned int save = get_current_state(); pr_debug("%s entered refrigerator\n", current->comm); --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8273,15 +8273,15 @@ static inline int preempt_count_equals(i void __might_sleep(const char *file, int line, int preempt_offset) { + unsigned int state = get_current_state(); /* * Blocking primitives will set (and therefore destroy) current->state, * since we will exit with TASK_RUNNING make sure we enter with it, * otherwise we will destroy state. */ - WARN_ONCE(current->state != TASK_RUNNING && current->task_state_change, + WARN_ONCE(state != TASK_RUNNING && current->task_state_change, "do not call blocking ops when !TASK_RUNNING; " - "state=%lx set at [<%p>] %pS\n", - current->state, + "state=%x set at [<%p>] %pS\n", state, (void *)current->task_state_change, (void *)current->task_state_change);