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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 2109FC2BA80 for ; Thu, 9 Apr 2020 02:11:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E8E6E206C0 for ; Thu, 9 Apr 2020 02:11:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586398285; bh=GA9a2/uAQ9YPaMNswPdlOkPg6vobi9RbIp96j/3SvVA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=PpJbRayG3xiDAkuc1Du7s1UCWNbtp8dJiEch/YmocECkarRIAEbNzi4WmWQpx/Uxo Lbo0V51vTOV/D+qIw0d7L7QTN5hnvkK4j0tCbLriyS3ErvjRusDik9A341Irdbj/DB bMc9E7oNZy4lnTrMP6+44v+PLItX33FfmvpIfACU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726589AbgDICLX (ORCPT ); Wed, 8 Apr 2020 22:11:23 -0400 Received: from mail-qv1-f68.google.com ([209.85.219.68]:39304 "EHLO mail-qv1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726521AbgDICLW (ORCPT ); Wed, 8 Apr 2020 22:11:22 -0400 Received: by mail-qv1-f68.google.com with SMTP id v38so4792894qvf.6; Wed, 08 Apr 2020 19:11:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=PORm90f1pekSo7bdM0jl5Wn3WR0naU3nSTdhyq8uYF0=; b=T7Rj9zyj69ZjK6UUEO6kzWCkTN/EwkDBjftpLUmOoy9ZB1aMICdyUvPrhIq0blPOXg a4mYkkazrJEhsteIcsHnJPqWFYq+z141WBvuBrxW8zrQqiX/C0Ys7B9XpXXKv9Hvzb/M bJxcXhcS62pgMWyykdwMuckw9Bu0QbBtd4wyDLaXCLO3TNufqMnjv2odgNsWl5Vjd9mj +OuDDXK11Z87WmD2bgPSFFTQKfbnTjJVF1ZUn0Tjl6Sl9rgvYCR6DrR3NPuOoZukSEMX 8pjlDSERna/H/T/2EikNzUzxvKbrn2zORX8dJ3+en8mV4cxuYQzhzYEl4rpXU/UTdSW4 ostQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=PORm90f1pekSo7bdM0jl5Wn3WR0naU3nSTdhyq8uYF0=; b=ZS9OQMFqWEOpv6YEfvedEpfxry53ZE/IIcBLxNcZH3reiE8BAA5OA2pClkzW3fkBBj rNnn6DYNb0TSbqkCJth434bd5P/vw/2cBnaq0Vbw+oLzhUbOe6/qk0D0JjvT1YdaN7Qd W149TJGDI1Cxqm+DPmn3i6/CllsFtDfPR6RKL46glN2qHWlK7qY/IxpoHjcig+RoPaCM sr2SmOUUyD9CVGopKqZiyckTiaW5LKZGT9ioEcY+T9SapBWSKQlPX7jXt6yOC/DSrVRC F7f+8Uaa+6oTV7VmOKku1Fj7VPu3GmzznjYQx41yHPTPaG0ZwGuuxUvFNiv6jhR4C0kW T1Fg== X-Gm-Message-State: AGi0PubUKkmxNOXHvw7BznNHrl1KX7l/m/fpjnMpjPnzJdXJ0941JetQ tSUdeF5RKbGeLIwWTCPvntg= X-Google-Smtp-Source: APiQypJotzBtsOA9saexNnYizl0kD5h0AWOt1lJg0kifNPqcHGFPhU5tyn3VYJ9TDHlIrhHAjMFWlQ== X-Received: by 2002:a0c:85c6:: with SMTP id o64mr876015qva.11.1586398281764; Wed, 08 Apr 2020 19:11:21 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::36b2]) by smtp.gmail.com with ESMTPSA id c6sm4248088qka.58.2020.04.08.19.11.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Apr 2020 19:11:21 -0700 (PDT) Date: Wed, 8 Apr 2020 22:11:19 -0400 From: Tejun Heo To: Ming Lei Cc: axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@vger.kernel.org, cgroups@vger.kernel.org, newella@fb.com, josef@toxicpanda.com Subject: Re: [PATCH 2/5] block: add request->io_data_len Message-ID: <20200409021119.GJ162390@mtj.duckdns.org> References: <20200408201450.3959560-1-tj@kernel.org> <20200408201450.3959560-3-tj@kernel.org> <20200409014406.GA370295@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200409014406.GA370295@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 09, 2020 at 09:44:06AM +0800, Ming Lei wrote: > Almost all __blk_mq_end_request() follow blk_update_request(), so the > completed bytes can be passed to __blk_mq_end_request(), then we can > avoid to introduce this field. But on some drivers blk_update_request() may be called multiple times before __blk_mq_end_request() is called and what's needed here is the total number of bytes in the whole request, not just in the final completion. > Also there is just 20 callers of __blk_mq_end_request(), looks this kind > of change shouldn't be too big. This would work iff we get rid of partial completions and if we get rid of partial completions, we might as well stop exposing blk_update_request() and __blk_mq_end_request(). Thanks. -- tejun