From patchwork Wed Jan 12 10:39:50 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Shilong X-Patchwork-Id: 211471 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1B4612C0362 for ; Sat, 12 Jan 2013 14:29:57 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754504Ab3ALD34 (ORCPT ); Fri, 11 Jan 2013 22:29:56 -0500 Received: from mail-yh0-f49.google.com ([209.85.213.49]:64412 "EHLO mail-yh0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753847Ab3ALD3z (ORCPT ); Fri, 11 Jan 2013 22:29:55 -0500 X-Greylist: delayed 3118 seconds by postgrey-1.27 at vger.kernel.org; Fri, 11 Jan 2013 22:29:55 EST Received: by mail-yh0-f49.google.com with SMTP id f43so452514yha.8 for ; Fri, 11 Jan 2013 19:29:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer; bh=wx+45connuJgpHIjyDfsmLOsAEvoll/Azt634OcposY=; b=rIgTcqGDTMTojmBRsiY6u1k+MNfb12IlkT8EJyqHCWyzPkMNFy2SRtvs00HYh/vsHo qgEMtNCq7vha6u7tlCOnKjxMvcyAEvcEM42I7sIOTanMB0I7ZrQaHi1GlVZEE6z+MNnO 9dsL6mMQKJqIttb3l5ZVDBgfYB953gMdCAjkF18M5MKE4nt8PEwpzHgBUklbZXUFZY3/ b/yfxHFIkw82i0IQh3vmxEtavWq//39Cyt27PazYG1hHTslXUwNnTk5AgNgiSjtiFpNG ArIsbBsfJv1X2DShFniJWHs0TJNH5SIF62OsBGaoOh8ZwscipFvvKBVZTNZboZjRVfbN YiPA== X-Received: by 10.236.140.107 with SMTP id d71mr87622438yhj.80.1357958276771; Fri, 11 Jan 2013 18:37:56 -0800 (PST) Received: from localhost.localdomain ([112.20.95.63]) by mx.google.com with ESMTPS id r9sm6216799yhm.14.2013.01.11.18.37.53 (version=TLSv1 cipher=RC4-SHA bits=128/128); Fri, 11 Jan 2013 18:37:55 -0800 (PST) From: Wang shilong To: tytso@mit.edu, adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org, Wang shilong , Wang Shilong Subject: [PATCH] Ext4: use 'unlikely' to improve the efficiency of the kernel Date: Wed, 12 Jan 2011 18:39:50 +0800 Message-Id: <1294828790-3455-1-git-send-email-wangshilong1991@gmail.com> X-Mailer: git-send-email 1.7.11.7 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: Wang Shilong Since 'sb_getblk' seldomly return NULL,it will be better to use 'unlikely' to check it. Signed-off-by: Wang Shilong --- fs/ext4/resize.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 7ea6cbb..2ef10e1 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -309,7 +309,7 @@ static struct buffer_head *bclean(handle_t *handle, struct super_block *sb, int err; bh = sb_getblk(sb, blk); - if (!bh) + if (unlikely(!bh)) return ERR_PTR(-EIO); if ((err = ext4_journal_get_write_access(handle, bh))) { brelse(bh); @@ -386,7 +386,7 @@ static int set_flexbg_block_bitmap(struct super_block *sb, handle_t *handle, return err; bh = sb_getblk(sb, flex_gd->groups[group].block_bitmap); - if (!bh) + if (unlikely(!bh)) return -EIO; err = ext4_journal_get_write_access(handle, bh); @@ -461,7 +461,7 @@ static int setup_new_flex_group_blocks(struct super_block *sb, goto out; gdb = sb_getblk(sb, block); - if (!gdb) { + if (unlikely(!gdb)) { err = -EIO; goto out; } @@ -983,7 +983,7 @@ static void update_backups(struct super_block *sb, break; bh = sb_getblk(sb, group * bpg + blk_off); - if (!bh) { + if (unlikely(!bh)) { err = -EIO; break; } @@ -1074,7 +1074,7 @@ static int ext4_add_new_descs(handle_t *handle, struct super_block *sb, static struct buffer_head *ext4_get_bitmap(struct super_block *sb, __u64 block) { struct buffer_head *bh = sb_getblk(sb, block); - if (!bh) + if (unlikely(!bh)) return NULL; if (bitmap_uptodate(bh))