Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751647Ab2JIBLU (ORCPT ); Mon, 8 Oct 2012 21:11:20 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:48601 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751078Ab2JIBLR (ORCPT ); Mon, 8 Oct 2012 21:11:17 -0400 Date: Tue, 9 Oct 2012 09:11:06 +0800 From: Shaohua Li To: axboe@kernel.dk Cc: linux-kernel@vger.kernel.org Subject: [patch]block: add plug for blkdev_issue_discard Message-ID: <20121009011106.GA17038@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1437 Lines: 43 Now discard merge works, add plug for blkdev_issue_discard. This will help discard request merge especially for raid0 case. In raid0, a big discard request is split to small requests, and if correct plug is added, such small requests can be merged in low layer. Signed-off-by: Shaohua Li --- block/blk-lib.c | 3 +++ 1 file changed, 3 insertions(+) Index: linux/block/blk-lib.c =================================================================== --- linux.orig/block/blk-lib.c 2012-09-28 15:09:38.655327319 +0800 +++ linux/block/blk-lib.c 2012-10-09 08:45:04.358598888 +0800 @@ -48,6 +48,7 @@ int blkdev_issue_discard(struct block_de struct bio_batch bb; struct bio *bio; int ret = 0; + struct blk_plug plug; if (!q) return -ENXIO; @@ -81,6 +82,7 @@ int blkdev_issue_discard(struct block_de bb.flags = 1 << BIO_UPTODATE; bb.wait = &wait; + blk_start_plug(&plug); while (nr_sects) { unsigned int req_sects; sector_t end_sect; @@ -117,6 +119,7 @@ int blkdev_issue_discard(struct block_de atomic_inc(&bb.done); submit_bio(type, bio); } + blk_finish_plug(&plug); /* Wait for bios in-flight */ if (!atomic_dec_and_test(&bb.done)) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/