From patchwork Fri Feb 28 17:46:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: madhuparnabhowmik10@gmail.com X-Patchwork-Id: 212698 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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 DEF01C3F2CD for ; Fri, 28 Feb 2020 17:47:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2788246A3 for ; Fri, 28 Feb 2020 17:47:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LJm/yUMM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725769AbgB1RrX (ORCPT ); Fri, 28 Feb 2020 12:47:23 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:35802 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725730AbgB1RrX (ORCPT ); Fri, 28 Feb 2020 12:47:23 -0500 Received: by mail-pj1-f67.google.com with SMTP id q39so1595387pjc.0; Fri, 28 Feb 2020 09:47:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=/ePEVzu9e29X32t3wuKx/BpiwqdFAtZzo2j4Ye/PyAI=; b=LJm/yUMM8qY9Sd7VgQAu2efugQyMRzQkJf2M7pKJfKSeC7+Y3MqFWqPOePjptFMcX4 0BjwICO4gfEeGTmNXsuBua+5tT9yIn8mLlbKmw9lv+vfxShZRV3rYB3PZ4I+bNXGLFUd mI/gsu14IHvA3EP8rggSh67w//AI91K/Y7ygE7i1upuVdQztAVcL5s5kJE41nPWpn8wI MroZov9GYjLvOlW1i3mFuFQn8/IFT8Y/S1wlaDgl4etydLwrrDu448tCcvlAWUpiloKf 79UQzRAQ2ZaFQxJY2W3r1fLlF/fii7qXwpJ6NcmHbNeGLGGpCajUuzSMu9NduI8gtw1W BHfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=/ePEVzu9e29X32t3wuKx/BpiwqdFAtZzo2j4Ye/PyAI=; b=MursuXD8KJno2mF/HqKzwLn3pSMEGiKtNBY19qEWnv2OFYzwVHbij4CZ0QPZQsFZ19 KkWQwqC0C/jfe2msuG1Ro61MnHbQcQ3YBvqMRQHgWI6YWY5L0j7wJO7dwB2owRTHNcA5 o/Xwy2Lovj6zCsFPDR6iFko95k49nUsfSdIH2Yi99dMcf6X4HNyqFYwetGamlI5ZjxhK ijEtoZ/OdDfC+eBPD16pwzTCwQA5BvMqt4VpqHmXlgpxSG5c/Bvu5iD+Fl1kIRliX5GH qegAHiZF79V8lyBSjGButJ7JfbHkd4IeYdPgFieaREAOYuQ27Ap50+nBAREr8riIB6zf WEvA== X-Gm-Message-State: APjAAAXyy9+NJCNe+OkkPewrARTT1QNN3GdYmriLzs+fei+8lXH3OC7i Q9H73vdhYmm49TFwVHHMSQ== X-Google-Smtp-Source: APXvYqx7VY1S5VZYqBM44Swe2WbZnQNZrK1WgQqQMKKWRP0e7OmJ4tiGUUnHgIfsmoPTjpkOwsYoWA== X-Received: by 2002:a17:90a:cf11:: with SMTP id h17mr5967943pju.103.1582912041716; Fri, 28 Feb 2020 09:47:21 -0800 (PST) Received: from madhuparna-HP-Notebook.nitk.ac.in ([2402:3a80:55e:f10b:ac46:7428:aa52:2d70]) by smtp.gmail.com with ESMTPSA id y15sm10679874pgj.78.2020.02.28.09.47.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Feb 2020 09:47:21 -0800 (PST) From: madhuparnabhowmik10@gmail.com To: rjw@rjwysocki.net, pavel@ucw.cz, len.brown@intel.com, gregkh@linuxfoundation.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, frextrite@gmail.com, linux-kernel-mentees@lists.linuxfoundation.org, paulmck@kernel.org, Madhuparna Bhowmik Subject: [PATCH 1/2] drivers: base: power: main: Use built-in RCU list checking Date: Fri, 28 Feb 2020 23:16:30 +0530 Message-Id: <20200228174630.8989-1-madhuparnabhowmik10@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Madhuparna Bhowmik This patch passes the cond argument to list_for_each_entry_rcu() to fix the following false-positive lockdep warnings: [ 330.302784] ============================= [ 330.302789] WARNING: suspicious RCU usage [ 330.302796] 5.6.0-rc1+ #5 Not tainted [ 330.302801] ----------------------------- [ 330.302808] drivers/base/power/main.c:326 RCU-list traversed in non-reader section!! [ 330.303303] ============================= [ 330.303307] WARNING: suspicious RCU usage [ 330.303311] 5.6.0-rc1+ #5 Not tainted [ 330.303315] ----------------------------- [ 330.303319] drivers/base/power/main.c:1698 RCU-list traversed in non-reader section!! [ 331.934969] ============================= [ 331.934971] WARNING: suspicious RCU usage [ 331.934973] 5.6.0-rc1+ #5 Not tainted [ 331.934975] ----------------------------- [ 331.934977] drivers/base/power/main.c:1238 RCU-list traversed in non-reader section!! [ 332.467772] WARNING: suspicious RCU usage [ 332.467775] 5.6.0-rc1+ #5 Not tainted [ 332.467775] ----------------------------- [ 332.467778] drivers/base/power/main.c:269 RCU-list traversed in non-reader section!! Signed-off-by: Madhuparna Bhowmik --- drivers/base/power/main.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 0e99a760aebd..742c05f3c1e7 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -266,7 +266,8 @@ static void dpm_wait_for_suppliers(struct device *dev, bool async) * callbacks freeing the link objects for the links in the list we're * walking. */ - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) if (READ_ONCE(link->status) != DL_STATE_DORMANT) dpm_wait(link->supplier, async); @@ -323,7 +324,8 @@ static void dpm_wait_for_consumers(struct device *dev, bool async) * continue instead of trying to continue in parallel with its * unregistration). */ - list_for_each_entry_rcu(link, &dev->links.consumers, s_node) + list_for_each_entry_rcu(link, &dev->links.consumers, s_node, + device_links_read_lock_held()) if (READ_ONCE(link->status) != DL_STATE_DORMANT) dpm_wait(link->consumer, async); @@ -1235,7 +1237,8 @@ static void dpm_superior_set_must_resume(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) link->supplier->power.must_resume = true; device_links_read_unlock(idx); @@ -1695,7 +1698,8 @@ static void dpm_clear_superiors_direct_complete(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { spin_lock_irq(&link->supplier->power.lock); link->supplier->power.direct_complete = false; spin_unlock_irq(&link->supplier->power.lock);