From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F24EDC43603 for ; Thu, 12 Dec 2019 06:04:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C87FE2464B for ; Thu, 12 Dec 2019 06:04:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726784AbfLLGEb (ORCPT ); Thu, 12 Dec 2019 01:04:31 -0500 Received: from mx2.suse.de ([195.135.220.15]:60748 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726775AbfLLGEb (ORCPT ); Thu, 12 Dec 2019 01:04:31 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 35B59AD75; Thu, 12 Dec 2019 06:04:29 +0000 (UTC) Subject: Re: [PATCH v3 3/4] xen/interface: re-define FRONT/BACK_RING_ATTACH() To: Paul Durrant , xen-devel@lists.xenproject.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Boris Ostrovsky , Stefano Stabellini References: <20191211152956.5168-1-pdurrant@amazon.com> <20191211152956.5168-4-pdurrant@amazon.com> From: =?UTF-8?B?SsO8cmdlbiBHcm/Dnw==?= Message-ID: Date: Thu, 12 Dec 2019 07:04:27 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <20191211152956.5168-4-pdurrant@amazon.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 11.12.19 16:29, Paul Durrant wrote: > Currently these macros are defined to re-initialize a front/back ring > (respectively) to values read from the shared ring in such a way that any > requests/responses that are added to the shared ring whilst the front/back > is detached will be skipped over. This, in general, is not a desirable > semantic since most frontend implementations will eventually block waiting > for a response which would either never appear or never be processed. > > Since the macros are currently unused, take this opportunity to re-define > them to re-initialize a front/back ring using specified values. This also > allows FRONT/BACK_RING_INIT() to be re-defined in terms of > FRONT/BACK_RING_ATTACH() using a specified value of 0. > > NOTE: BACK_RING_ATTACH() will be used directly in a subsequent patch. > > Signed-off-by: Paul Durrant Reviewed-by: Juergen Gross Juergen