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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 09D8DC2BA4C for ; Wed, 26 Jan 2022 05:50:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=J1F7j6+C8DXHO5fhIXVaDrpLS8SUodnhoTv2SytMx5E=; b=knsCKwO3ykRTO5i88EYqP56r0V T9rIPlTqya/u7dEUG/lNP/mB0//+s4Lq6qh3iQbm1oWUB0JHC3UdG51U9QUtUcDlPkEiUXi8nEMmj YWvYULq2sCvc36mAeZK19NPRKferZRTRzb4+t4CH16p7ay1Zmj64F/Wr7O2AxjPXpdHZG4o5OCNFz hCSIUdjw+gOQ6EsU2OTvYvAkZLcXGgUrUvLABjzEsxN0kmXnXRi3Di9kq/AabOZWRxnsDA2NsNTiv Rx2MDn5CZzHxal5fdKeBHb43YUJ8pUpGHLdTbFpB8yyrhRuJBZoSEv5kmpxVDmHtJGapWi+VLsiIz gI7eWzlA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nCbC8-00AE9t-Cc; Wed, 26 Jan 2022 05:50:12 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nCbC5-00AE8y-Ok for linux-nvme@lists.infradead.org; Wed, 26 Jan 2022 05:50:11 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 2E30867373; Wed, 26 Jan 2022 06:50:04 +0100 (CET) Date: Wed, 26 Jan 2022 06:50:03 +0100 From: Christoph Hellwig To: Ming Lei Cc: Christoph Hellwig , Jens Axboe , "Martin K . Petersen" , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org Subject: Re: [PATCH V2 05/13] block: only account passthrough IO from userspace Message-ID: <20220126055003.GA21089@lst.de> References: <20220122111054.1126146-1-ming.lei@redhat.com> <20220122111054.1126146-6-ming.lei@redhat.com> <20220124130555.GD27269@lst.de> <20220125061634.GA26495@lst.de> <20220125071906.GA27674@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220125_215009_980888_F71C8F9C X-CRM114-Status: GOOD ( 14.79 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Jan 25, 2022 at 05:09:42PM +0800, Ming Lei wrote: > Follows another simple way by accounting all request with bio attached, > except for requests with kernel buffer. > - else if (rq->q->disk) > + else if (rq->q->disk && rq->bio) > rq->part = rq->q->disk->part0; Most passthrough requests will have a bio, so you'll still use e.g. the sd gendisk for sg request here. I think the right way would be to just remove this branch entirely. This means we only account bios with a block_device, which implies they have a gendisk.