From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 9B2337D90D for ; Wed, 14 Aug 2019 22:42:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728758AbfHNWmI (ORCPT ); Wed, 14 Aug 2019 18:42:08 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:39790 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728378AbfHNWmI (ORCPT ); Wed, 14 Aug 2019 18:42:08 -0400 Received: by mail-pl1-f195.google.com with SMTP id z3so258680pln.6 for ; Wed, 14 Aug 2019 15:42:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=hMEHK3D0DeqRXHR3V666QBC5hkX1AwG9+yo5maZ51Ws=; b=PzkYxpR+WsvJ0GKSPP9wt0l4YqVfxxZlRPySwxDENc0uquYDE4FH3bIiRoxfTPA1v0 daLJqf8B4sQuDac5d61sdyojfc8b9g9yhK52TGU9vCCC2Q6Ozm2F1P/8FaMyzsrTVEb0 3Xm3jaPn/9nJxAF4SojpaoPdnkNoRcv5nmLjQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=hMEHK3D0DeqRXHR3V666QBC5hkX1AwG9+yo5maZ51Ws=; b=LyzwrZdIccGNPiRI/y4/OSOWeFv64HZNX/wOqF09HAzhSE1DKVw8cvxXBEXOiBJ+Ge /vDCwZPVciua2HhdWjCIe6YLe4hQaG22zmbTIYz5TYM9r3gndSY2H0HlZMTxZ9CPClZz IYJ9bYfGBdX70mxeEtwL9KQxjLSoGREPdhhwCvjlgLs/JPtSAKq791FoMsiJwUDkaeCR dyjJ+hxaXdupk4LQLizEbFam9NN70c0zP3mZTZyChIbukld8LP+88qtH5O1eavs0YWu8 u6ibPkL+/uNzefjyv3peeO1eaedgOWQ7SRKcPeqxgmRr8Zvuf8OSLAJqaj5HPW9DsIJU uqig== X-Gm-Message-State: APjAAAU7BjnT0oBGO7L+ypZHZV2RitJASGvBW1crP2nzHwc8NZrhqVCQ jRHtEcbiOgARdfGC6fE7NUXShw== X-Google-Smtp-Source: APXvYqxeCtn5YQ0RrQb6xdht/iQSMOK2IulsqUWdD2tppaE3yQNeQo12jNVOsbuEuixCZiNvYLOGgg== X-Received: by 2002:a17:902:2f05:: with SMTP id s5mr1571241plb.170.1565822527290; Wed, 14 Aug 2019 15:42:07 -0700 (PDT) Received: from localhost ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id v6sm31357pjn.13.2019.08.14.15.42.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Aug 2019 15:42:06 -0700 (PDT) Date: Wed, 14 Aug 2019 18:42:05 -0400 From: Joel Fernandes To: Tejun Heo Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Jonathan Corbet , Josh Triplett , Lai Jiangshan , linux-doc@vger.kernel.org, Mathieu Desnoyers , "Paul E. McKenney" , "Rafael J. Wysocki" , rcu@vger.kernel.org, Steven Rostedt Subject: Re: [PATCH 1/3] workqueue: Convert for_each_wq to use built-in list check (v2) Message-ID: <20190814224205.GC69375@google.com> References: <20190811221111.99401-1-joel@joelfernandes.org> <20190814194841.GA588936@devbig004.ftw2.facebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190814194841.GA588936@devbig004.ftw2.facebook.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Wed, Aug 14, 2019 at 12:48:41PM -0700, Tejun Heo wrote: > Hello, Joel. > > On Sun, Aug 11, 2019 at 06:11:09PM -0400, Joel Fernandes (Google) wrote: > > list_for_each_entry_rcu now has support to check for RCU reader sections > > as well as lock. Just use the support in it, instead of explicitly > > checking in the caller. > > > > Signed-off-by: Joel Fernandes (Google) > > Acked-by: Tejun Heo Thanks. > > #define for_each_pwq(pwq, wq) \ > > - list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node) \ > > - if (({ assert_rcu_or_wq_mutex(wq); false; })) { } \ > > - else > > + list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node, \ > > + lock_is_held(&(wq->mutex).dep_map)) > > Why not lockdep_is_held() tho? Yes, that's better. thanks, - Joel