From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754577AbbDTP6z (ORCPT ); Mon, 20 Apr 2015 11:58:55 -0400 Received: from mail-pd0-f180.google.com ([209.85.192.180]:33348 "EHLO mail-pd0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752180AbbDTP6w (ORCPT ); Mon, 20 Apr 2015 11:58:52 -0400 Message-ID: <55352238.1020301@kernel.dk> Date: Mon, 20 Apr 2015 09:58:48 -0600 From: Jens Axboe User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Jeff Moyer , lkml Subject: Re: BLK_MQ_F_DEFER_ISSUE References: In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/20/2015 09:09 AM, Jeff Moyer wrote: > Hi, Jens, > > This flag was introduced under the auspices that the nvme blk-mq > conversion would make use of it. That never materialized. Are there > still plans to make use of it? If not, I'd like to get rid of it. If > so, then let's document it better. Yep I still want to use it, and I do have a patch that uses it as well that I've run through testing. I thought I had pushed it somewhere, but it doesn't seem like I have. I just wanted to get the lower hanging optimizations out there first, like the kmalloc/kfree and queue-lock-for-completions removal. Former is in, latter is not yet. It's a useful optimization for lots of cases and I'm sure it'll see other uses, once the nvme patch is in. That will give people a reference point. -- Jens Axboe