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[209.132.180.67]) by mx.google.com with ESMTP id m1si5689667pgm.413.2018.03.30.07.47.16; Fri, 30 Mar 2018 07:47:30 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@codeaurora.org header.s=default header.b=UyKPfHDo; dkim=pass header.i=@codeaurora.org header.s=default header.b=UyKPfHDo; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752269AbeC3OqK (ORCPT + 99 others); Fri, 30 Mar 2018 10:46:10 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:59500 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751254AbeC3OqI (ORCPT ); Fri, 30 Mar 2018 10:46:08 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id EAE0760AE0; Fri, 30 Mar 2018 14:46:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1522421167; bh=hCU+I9vkfUXTIiWoSg1Qi3tiOCU8d4OgoRYFjGc6+0Q=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=UyKPfHDoQed4aVtRym+7zkqwsUDPgeBueA0Z2Cn16Iz4q/azWNWV7EuYREH5uv+gp To6mXibEwDH8pCqpM2m5hSQKm/9gxGnUZTL40Js+Xj6778IfqQdCAu7aYJXwEjO4vx LZ4S94lh+Shvcr0yZSTrr5bTitPJluF1G+faFmOg= X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=2.0 tests=ALL_TRUSTED,BAYES_00, DKIM_SIGNED,T_DKIM_INVALID autolearn=no autolearn_force=no version=3.4.0 Received: from [172.17.0.162] (unknown [108.175.202.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id DA1646070A; Fri, 30 Mar 2018 14:46:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1522421167; bh=hCU+I9vkfUXTIiWoSg1Qi3tiOCU8d4OgoRYFjGc6+0Q=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=UyKPfHDoQed4aVtRym+7zkqwsUDPgeBueA0Z2Cn16Iz4q/azWNWV7EuYREH5uv+gp To6mXibEwDH8pCqpM2m5hSQKm/9gxGnUZTL40Js+Xj6778IfqQdCAu7aYJXwEjO4vx LZ4S94lh+Shvcr0yZSTrr5bTitPJluF1G+faFmOg= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org DA1646070A Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org Subject: Re: [PATCH] io: prevent compiler reordering on the default writeX() implementation To: arnd@arndb.de, timur@codeaurora.org, sulrich@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org References: <1522420199-23548-1-git-send-email-okaya@codeaurora.org> From: Sinan Kaya Message-ID: <4e3acc1a-0c06-5b1b-1b87-91bef2daae38@codeaurora.org> Date: Fri, 30 Mar 2018 10:46:05 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1522420199-23548-1-git-send-email-okaya@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/30/2018 10:29 AM, Sinan Kaya wrote: > In the abscence of a write barrier or when using a strongly ordered > architecture, writeX() should at least have a compiler barrier in > it to prevent commpiler from clobbering the execution order. Same is true for readX(). I'll wait for review feedback on this before posting another change for readX(). -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.