From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752450AbaE0PIp (ORCPT ); Tue, 27 May 2014 11:08:45 -0400 Received: from mail-pb0-f54.google.com ([209.85.160.54]:43003 "EHLO mail-pb0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751615AbaE0PIo (ORCPT ); Tue, 27 May 2014 11:08:44 -0400 Message-ID: <5384AA79.4010206@kernel.dk> Date: Tue, 27 May 2014 09:08:41 -0600 From: Jens Axboe User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Mikulas Patocka , Kent Overstreet CC: linux-kernel@vger.kernel.org, dm-devel@redhat.com, "Alasdair G. Kergon" , Mike Snitzer Subject: Re: [PATCH] block: flush queued bios when the process blocks References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014-05-27 09:03, Mikulas Patocka wrote: > The block layer uses per-process bio list to avoid recursion in > generic_make_request. When generic_make_request is called recursively, the > bio is added to current->bio_list and the function returns immediatelly. > The top-level instance of generic_make_requests takes bios from > current->bio_list and processes them. This really begs the question of why we just don't use the per-process plugs for this. We already have scheduler hooks in place to flush those at the appropriate time. Why are we reinventing something for essentially the same thing? -- Jens Axboe