Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263580AbUDPSY7 (ORCPT ); Fri, 16 Apr 2004 14:24:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263593AbUDPSY7 (ORCPT ); Fri, 16 Apr 2004 14:24:59 -0400 Received: from e35.co.us.ibm.com ([32.97.110.133]:56705 "EHLO e35.co.us.ibm.com") by vger.kernel.org with ESMTP id S263580AbUDPSY6 (ORCPT ); Fri, 16 Apr 2004 14:24:58 -0400 Message-ID: <408024CA.8000401@us.ibm.com> Date: Fri, 16 Apr 2004 13:24:10 -0500 From: Brian King User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.1) Gecko/20020827 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Jeff Garzik CC: "Bagalkote, Sreenivas" , "'Matt_Domsch@dell.com'" , "'paul@kungfoocoder.org'" , "Mukker, Atul" , "'James.Bottomley@SteelEye.com'" , "'arjanv@redhat.com'" , "'linux-scsi@vger.kernel.org'" , "'linux-kernel@vger.kernel.org'" Subject: Re: [PATCH][RELEASE]: megaraid unified driver version 2.20.0.B1 References: <0E3FA95632D6D047BA649F95DAB60E570230C7DB@exa-atlanta.se.lsil.com> <40801F5D.7030100@pobox.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 831 Lines: 22 Jeff Garzik wrote: > 6) Kill uses of "volatile". _Most_ of the time, this indicates buggy > code. You should have the proper barriers in place: mb(), wmb(), > rmb(), barrier(), and cpu_relax(). This has been mentioned before :) I'm not sure I totally agree with this statement. I took a quick look at the driver and the volatile appears to be used to point to host memory that is modified by the adapter. Correct me if I am wrong, but memory barriers will not accomplish what the volatile will in this situation. -- Brian King eServer Storage I/O IBM Linux Technology Center - 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/