From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756367AbdJJOGe (ORCPT ); Tue, 10 Oct 2017 10:06:34 -0400 Received: from mail-qt0-f182.google.com ([209.85.216.182]:44163 "EHLO mail-qt0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756331AbdJJOGd (ORCPT ); Tue, 10 Oct 2017 10:06:33 -0400 X-Google-Smtp-Source: AOwi7QDvpN2MNwimxnWq6nVlYamoA425xt40nH6+zzg/8tBZ0UVxk6fJLyQA3PhETgsy+XHWRhmD2w== Date: Tue, 10 Oct 2017 07:06:29 -0700 From: Tejun Heo To: Mark Rutland Cc: linux-kernel@vger.kernel.org, Lai Jiangshan Subject: Re: [PATCH 12/13] workqueue: kill off ACCESS_ONCE() Message-ID: <20171010140629.GJ3301751@devbig577.frc2.facebook.com> References: <1507573730-8083-1-git-send-email-mark.rutland@arm.com> <1507573730-8083-13-git-send-email-mark.rutland@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1507573730-8083-13-git-send-email-mark.rutland@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 09, 2017 at 07:28:49PM +0100, Mark Rutland wrote: > For several reasons, it is desirable to use {READ,WRITE}_ONCE() in > preference to ACCESS_ONCE(), and new code is expected to use one of the > former. So far, there's been no reason to change most existing uses of > ACCESS_ONCE(), as these aren't currently harmful. > > However, for some features it is necessary to instrument reads and > writes separately, which is not possible with ACCESS_ONCE(). This > distinction is critical to correct operation. > > It's possible to transform the bulk of kernel code using the Coccinelle > script below. However, this doesn't handle comments, leaving references > to ACCESS_ONCE() instances which have been removed. As a preparatory > step, this patch converts the workqueue code and comments to use > {READ,WRITE}_ONCE() consistently. ... > Signed-off-by: Mark Rutland > Cc: Lai Jiangshan > Cc: Tejun Heo Acked-by: Tejun Heo If you want me to route it through the workqueue tree, please let me know. Thanks. -- tejun