From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753917Ab0F1MeQ (ORCPT ); Mon, 28 Jun 2010 08:34:16 -0400 Received: from 0122700014.0.fullrate.dk ([95.166.99.235]:33690 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752410Ab0F1MeO (ORCPT ); Mon, 28 Jun 2010 08:34:14 -0400 Message-ID: <4C2896C6.9030607@kernel.dk> Date: Mon, 28 Jun 2010 14:34:14 +0200 From: Jens Axboe MIME-Version: 1.0 To: Mike Snitzer CC: Christoph Hellwig , dm-devel@redhat.com, James.Bottomley@suse.de, linux-kernel@vger.kernel.org, martin.petersen@oracle.com, akpm@linux-foundation.org Subject: Re: [PATCH 2/2] block: defer the use of inline biovecs for discard requests References: <20100622180029.GA15950@redhat.com> <1277582211-10725-2-git-send-email-snitzer@redhat.com> In-Reply-To: <1277582211-10725-2-git-send-email-snitzer@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2010-06-26 21:56, Mike Snitzer wrote: > Don't alloc discard bio with a biovec in blkdev_issue_discard. Doing so > means bio_has_data() will not be true until the SCSI layer adds the > payload to the discard request via blk_add_request_payload. Sorry, this looks horrible. What is the point of this?! > bio_{enable,disable}_inline_vecs are not expected to be widely used so > they were exported using EXPORT_SYMBOL_GPL. Never export anything that doesn't have an in-kernel modular user. > This patch avoids the need for the following VM accounting fix for > discards: http://lkml.org/lkml/2010/6/23/361 > NOTE: Jens, you said you applied Tao Ma's fix but I cannot see it in > your linux-2.6-block's for-next or for-2.6.36... as such I didn't revert > it in this patch. It's in the for-linus branch, that is stuff headed for the current kernel. -- Jens Axboe