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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 44FC4C43441 for ; Thu, 29 Nov 2018 15:45:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CDEB213A2 for ; Thu, 29 Nov 2018 15:45:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="BPfoTj08" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0CDEB213A2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-block-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728505AbeK3Cve (ORCPT ); Thu, 29 Nov 2018 21:51:34 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:58828 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728363AbeK3Cvd (ORCPT ); Thu, 29 Nov 2018 21:51:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=kTVgrl4jhJtumWMmgq9wq9UTYKLKOKwa22M+QKICU/I=; b=BPfoTj08PW8OgeKW6TpjXfB63 93IYiyTDBXdShh/zo8Jyck9ijJb8P/3AiNALvn2mH8szTxTPHYl81uz3cFGc5ORP4psMVWeV4wXs9 B8CfYxPZsT15M/7TP7hK2meuTm+o4HoNYGS5oXH1MdtFvrOhccCozEhXXnrzzN928V4OWLxb8kiX2 W+XfLL2mpJxO9A8whGR9yW9Rv/U/YZb7IG5a2kMtvy6Uf+KPYAaPp8qLrCOS40xSXZjOZZ81VPr5A Pddxzptwm5Q1lh60L+poJD6tHkkl5riL1csXZkalYrFmvi1fHhfp9nxardsYZFtMSMSlyrTslbyFv suf306S9g==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gSOVe-0003xd-GD; Thu, 29 Nov 2018 15:45:46 +0000 Date: Thu, 29 Nov 2018 07:45:46 -0800 From: Christoph Hellwig To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org Subject: Re: [PATCH 2/7] blk-mq: add mq_ops->commit_rqs() Message-ID: <20181129154546.GB7234@infradead.org> References: <20181128133538.20329-1-axboe@kernel.dk> <20181128133538.20329-3-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181128133538.20329-3-axboe@kernel.dk> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, Nov 28, 2018 at 06:35:33AM -0700, Jens Axboe wrote: > blk-mq passes information to the hardware about any given request being > the last that we will issue in this sequence. The point is that hardware > can defer costly doorbell type writes to the last request. But if we run > into errors issuing a sequence of requests, we may never send the request > with bd->last == true set. For that case, we need a hook that tells the > hardware that nothing else is coming right now. > > For failures returned by the drivers ->queue_rq() hook, the driver is > responsible for flushing pending requests, if it uses bd->last to > optimize that part. This works like before, no changes there. > > Reviewed-by: Omar Sandoval > Reviewed-by: Ming Lei > Reviewed-by: Christoph Hellwig I don't think I actually reviewed it before in this form. But now that I took a look it does indeed look fine to me: Reviewed-by: Christoph Hellwig