From nobody Thu Oct 2 18:17:40 2025 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 91946C7619A for ; Wed, 12 Apr 2023 02:38:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229533AbjDLCip (ORCPT ); Tue, 11 Apr 2023 22:38:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229481AbjDLCio (ORCPT ); Tue, 11 Apr 2023 22:38:44 -0400 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2ECF840D8 for ; Tue, 11 Apr 2023 19:38:43 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id d2e1a72fcca58-63af68592f0so859950b3a.1 for ; Tue, 11 Apr 2023 19:38:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681267122; x=1683859122; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=RNWG2HLYVu8lISkZ1sV4u+6+PLx7BcJ7lAq9oMLMvNk=; b=he62bc8OveLb0DVwvJVNFeL8V9939ycFrKnUYdFQveUBL6N8KkND5MSvuP7n0DMR3I qcv8jPZ2mpLHZ2ATdlDQaERA3ie780MAiMLaOB6fIKe13CHm+J9Xxpt59jLJiVwAjNfe sCg+faCVAXXsYScFe8ETvtzBFg5G/5NrTrnxa4JFQNymZiDDOF1dBOp4JONT0MmUQ6c7 QPqkAX8pQYakP6xFuTb5rReqycTe5bpeWtPZvcvgYweS96ActIKmr6uwaDMBlKMQZAgP 6uMdd1JtpdKeXUC77A7OT/nv4ApemHGnE8jq9dGJA3LxGlaUXnOSLaQo9tsLs5qHgHq7 jeow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1681267122; x=1683859122; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=RNWG2HLYVu8lISkZ1sV4u+6+PLx7BcJ7lAq9oMLMvNk=; b=7TRik38Q2Z6oqzp+OEoEqkitJYd+ej99/rsEJks+On6s2j4lz7xWeBWGH9aIzYjuof Mz1BZOfAfmVHvohCccr/BHowtXwFEEQL0MBrXFjctHMG/0EtbTdKq1MSFGQ4qs6MCOjr ALWZ6DiYtiSSNV8ldWUkOI+NLtm2IUhodeczJ7pMA/KHFnFvClokRAXsN4p7/xo45ost OlEsIpGG0KOK/bLWO61HvdlSGYfsPwmqABQ4OZxnMPGge7WOs+tK+TmuR6k/RcsK6ek4 5aPJXqLvZ+drqIV5FMU+4rT5h82RWqN60PlH5CNAWt4NVCJPKwx1qCRgtXWUxIBNa1kO zepw== X-Gm-Message-State: AAQBX9eN6nyh5zgiYAZakfE2jzZq1fmvQ7qjooJyJF8zx+Ln8lwRuUut p5OvwZt/1kNDpE5qr2LIO0UYSINPsKg19jxv8TX8unBmRt4hiLwN+fdYRboHrzjGP1hWisy/DPK BttfRZcorYi4wLydNKLTDuzzck69ug752PXfK+phXjTyYgY1/69bEaF0JsagUAZnRxt19eQs= X-Google-Smtp-Source: AKy350bDT1s8PAqQU63jFNJ65fDC8ReNM/DryIQ8gPGrrq5Vrqhki098rPAbm73qeZxAqs+8RhGiflRK3iUR X-Received: from jstultz-noogler2.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:600]) (user=jstultz job=sendgmr) by 2002:a05:6a00:1ca4:b0:63a:2000:6e0c with SMTP id y36-20020a056a001ca400b0063a20006e0cmr545417pfw.3.1681267122451; Tue, 11 Apr 2023 19:38:42 -0700 (PDT) Date: Wed, 12 Apr 2023 02:38:39 +0000 Mime-Version: 1.0 X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230412023839.2869114-1-jstultz@google.com> Subject: [RFC][PATCH] locking/rwsem: Add __sched annotation to __down_read_common() From: John Stultz To: LKML Cc: John Stultz , Minchan Kim , Tim Murray , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long , Boqun Feng , kernel-team@android.com, stable@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Apparently despite it being marked inline, the compiler may not inline __down_read_common() which makes it difficult to identify the cause of lock contention, as the blocked function will always be listed as __down_read_common(). So this patch adds __sched annotation to the function so the calling function will instead be listed. Cc: Minchan Kim Cc: Tim Murray Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Cc: kernel-team@android.com Cc: stable@vger.kernel.org Fixes: c995e638ccbb ("locking/rwsem: Fold __down_{read,write}*()") Reported-by: Tim Murray Signed-off-by: John Stultz --- kernel/locking/rwsem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index acb5a50309a1..cde2f22e65a8 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -1240,7 +1240,7 @@ static struct rw_semaphore *rwsem_downgrade_wake(stru= ct rw_semaphore *sem) /* * lock for reading */ -static inline int __down_read_common(struct rw_semaphore *sem, int state) +static inline __sched int __down_read_common(struct rw_semaphore *sem, int= state) { int ret =3D 0; long count; --=20 2.40.0.577.gac1e443424-goog