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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84663C28CF5 for ; Wed, 26 Jan 2022 07:21:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237710AbiAZHVa (ORCPT ); Wed, 26 Jan 2022 02:21:30 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:27322 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229641AbiAZHV1 (ORCPT ); Wed, 26 Jan 2022 02:21:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643181686; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ChzXGjDq+n0o2fu8dy3EjJHxjjUhkcJ57NGo6xi+9ws=; b=G6zhpwUeQtEbI0OUDFUmtWXOsZF64lNxjR5ojGvD08JbzpOxOxHwcZBNWnc2jThWR4UgYC LwUbk5aHJsMLCRTk8KHS1gXlm3PpupgYlJO2zPJV+Ia8yhFqkFXOoE6APi/Xl8gZoFF/mn cqO9Im911OGoFOdQnvQelNwrfoGbI+E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-134-2_DijEOSOzidwZtTm4ux6Q-1; Wed, 26 Jan 2022 02:21:22 -0500 X-MC-Unique: 2_DijEOSOzidwZtTm4ux6Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3647A18C89DD; Wed, 26 Jan 2022 07:21:21 +0000 (UTC) Received: from T590 (ovpn-8-26.pek2.redhat.com [10.72.8.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id ECBB410589BC; Wed, 26 Jan 2022 07:21:09 +0000 (UTC) Date: Wed, 26 Jan 2022 15:21:04 +0800 From: Ming Lei To: Christoph Hellwig Cc: 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: 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> <20220126055003.GA21089@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220126055003.GA21089@lst.de> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On Wed, Jan 26, 2022 at 06:50:03AM +0100, Christoph Hellwig wrote: > 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. That will not account userspace IO, and people may complain. We can just account passthrough request from userspace by the patch in my last email. Thanks, Ming