From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: [PATCH 12/15] swap: do not send discards as barriers Date: Wed, 18 Aug 2010 05:29:20 -0400 Message-ID: <20100818093502.062639046@bombadil.infradead.org> References: <20100818093432.646633424@bombadil.infradead.org> Cc: 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: tj@kernel.org Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:48827 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752623Ab0HRJff (ORCPT ); Wed, 18 Aug 2010 05:35:35 -0400 Content-Disposition: inline; filename=swap-discard-nobarrier Sender: linux-fsdevel-owner@vger.kernel.org List-ID: The swap code already uses synchronous discards, no need to add I/O barriers. Signed-off-by: Christoph Hellwig Index: linux-2.6/mm/swapfile.c =================================================================== --- linux-2.6.orig/mm/swapfile.c 2010-08-17 16:49:28.312010428 +0200 +++ linux-2.6/mm/swapfile.c 2010-08-17 16:49:43.694255853 +0200 @@ -140,7 +140,7 @@ static int discard_swap(struct swap_info if (nr_blocks) { err = blkdev_issue_discard(si->bdev, start_block, nr_blocks, GFP_KERNEL, - BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER); + BLKDEV_IFL_WAIT); if (err) return err; cond_resched(); @@ -152,7 +152,7 @@ static int discard_swap(struct swap_info err = blkdev_issue_discard(si->bdev, start_block, nr_blocks, GFP_KERNEL, - BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER); + BLKDEV_IFL_WAIT); if (err) break; @@ -191,8 +191,7 @@ static void discard_swap_cluster(struct start_block <<= PAGE_SHIFT - 9; nr_blocks <<= PAGE_SHIFT - 9; if (blkdev_issue_discard(si->bdev, start_block, - nr_blocks, GFP_NOIO, BLKDEV_IFL_WAIT | - BLKDEV_IFL_BARRIER)) + nr_blocks, GFP_NOIO, BLKDEV_IFL_WAIT)) break; }