Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759374Ab0FJPYy (ORCPT ); Thu, 10 Jun 2010 11:24:54 -0400 Received: from hera.kernel.org ([140.211.167.34]:32949 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753968Ab0FJPYw (ORCPT ); Thu, 10 Jun 2010 11:24:52 -0400 Message-ID: <4C1103B1.7050307@kernel.org> Date: Thu, 10 Jun 2010 17:24:33 +0200 From: Tejun Heo User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.1.9) Gecko/20100317 Thunderbird/3.0.4 MIME-Version: 1.0 To: Catalin Marinas CC: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, Colin Tuckley Subject: Re: [PATCH] sata_sil24: Use memory barriers before issuing commands References: <20100610145706.15588.4562.stgit@e102109-lin.cambridge.arm.com> In-Reply-To: <20100610145706.15588.4562.stgit@e102109-lin.cambridge.arm.com> X-Enigmail-Version: 1.0.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 10 Jun 2010 15:24:35 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 697 Lines: 20 On 06/10/2010 04:57 PM, Catalin Marinas wrote: > The data in the cmd_block buffers may reach the main memory after the > writel() to the device ports. This patch introduces two calls to wmb() > to ensure the relative ordering. > > Signed-off-by: Catalin Marinas > Tested-by: Colin Tuckley > Cc: Tejun Heo Can you please add comments explaining why they're needed? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/