From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753807AbbDTQER (ORCPT ); Mon, 20 Apr 2015 12:04:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54319 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750829AbbDTQEP (ORCPT ); Mon, 20 Apr 2015 12:04:15 -0400 From: Jeff Moyer To: Jens Axboe Cc: lkml Subject: Re: BLK_MQ_F_DEFER_ISSUE References: <55352238.1020301@kernel.dk> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Mon, 20 Apr 2015 12:04:14 -0400 In-Reply-To: <55352238.1020301@kernel.dk> (Jens Axboe's message of "Mon, 20 Apr 2015 09:58:48 -0600") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jens Axboe writes: > 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. OK, thanks for the quick reply. -Jeff