From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: Re: [PATCH 10/15] ext4: do not send discards as barriers Date: Wed, 18 Aug 2010 15:28:30 +0200 Message-ID: <20100818132829.GC4680@quack.suse.cz> References: <20100818093432.646633424@bombadil.infradead.org> <20100818093501.533010053@bombadil.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: tj@kernel.org, chris.mason@oracle.com, swhiteho@redhat.com, konishi.ryusuke@lab.ntt.co.jp, tytso@mit.edu, jack@suse.cz, hirofumi@mail.parknet.co.jp, mfasheh@suse.com, joel.becker@oracle.com, hughd@google.com, linux-fsdevel@vger.kernel.org To: Christoph Hellwig Return-path: Received: from cantor2.suse.de ([195.135.220.15]:47689 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752926Ab0HRN3M (ORCPT ); Wed, 18 Aug 2010 09:29:12 -0400 Content-Disposition: inline In-Reply-To: <20100818093501.533010053@bombadil.infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed 18-08-10 05:29:18, Christoph Hellwig wrote: > ext4 already uses synchronous discards, no need to add I/O barriers. The patch looks ok. But note that in -rc1 the code looks sligthly differently so you'll need to rediff it. Honza > > Signed-off-by: Christoph Hellwig > > Index: linux-2.6/fs/ext4/mballoc.c > =================================================================== > --- linux-2.6.orig/fs/ext4/mballoc.c 2010-08-17 16:48:50.546274081 +0200 > +++ linux-2.6/fs/ext4/mballoc.c 2010-08-17 16:48:58.896006097 +0200 > @@ -2589,9 +2589,7 @@ static void release_blocks_on_commit(jou > (unsigned long long)discard_block, > entry->count); > ret = sb_issue_discard(sb, discard_block, entry->count, > - GFP_NOFS, > - BLKDEV_IFL_WAIT | > - BLKDEV_IFL_BARRIER); > + GFP_NOFS, BLKDEV_IFL_WAIT); > if (ret == EOPNOTSUPP) { > ext4_warning(sb, > "discard not supported, disabling"); > -- Jan Kara SUSE Labs, CR