From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753967AbYIZSxe (ORCPT ); Fri, 26 Sep 2008 14:53:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753513AbYIZSxR (ORCPT ); Fri, 26 Sep 2008 14:53:17 -0400 Received: from ti-out-0910.google.com ([209.85.142.184]:57865 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753328AbYIZSxQ (ORCPT ); Fri, 26 Sep 2008 14:53:16 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=k+qBOrE7xtEK3cJ2qaLYxwqFj6gE7pmkd3sEsotJMqibL2kpeWMtifIzgoDqmsZoZ3 fZL/h1MvVQXCshynDgQFnMgGrmpkQVZYpkA5tziAFbsnuUVPC0TYleNuGeIGWOZHLbrk N1agtdX3HyzurYUK2SHfvlGoDQv/LhPaFx2l8= From: Denis ChengRq To: Al Viro Cc: Andrew Morton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] fs/block_dev.c: __read_mostly improvement and sb_is_blkdev_sb utilization Date: Sat, 27 Sep 2008 02:52:59 +0800 Message-Id: <1222455179-29953-1-git-send-email-crquan@gmail.com> X-Mailer: git-send-email 1.5.6.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This simple patch includes serveral improvements: 1. iget5_locked in bdget really needs blockdev_superblock, instead of bd_mnt, so bd_mnt could be just a local variable; 2. blockdev_superblock really needs __read_mostly, while local var bd_mnt not; 3. make use of sb_is_blkdev_sb in bd_forget, instead of direct reference to blockdev_superblock. Signed-off-by: Denis ChengRq --- fs/block_dev.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/block_dev.c b/fs/block_dev.c index aff5421..6d8a3ca 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -326,12 +326,13 @@ static struct file_system_type bd_type = { .kill_sb = kill_anon_super, }; -static struct vfsmount *bd_mnt __read_mostly; -struct super_block *blockdev_superblock; +struct super_block *blockdev_superblock __read_mostly; void __init bdev_cache_init(void) { int err; + struct vfsmount *bd_mnt; + bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode), 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| SLAB_MEM_SPREAD|SLAB_PANIC), @@ -373,7 +374,7 @@ struct block_device *bdget(dev_t dev) struct block_device *bdev; struct inode *inode; - inode = iget5_locked(bd_mnt->mnt_sb, hash(dev), + inode = iget5_locked(blockdev_superblock, hash(dev), bdev_test, bdev_set, &dev); if (!inode) @@ -463,7 +464,7 @@ void bd_forget(struct inode *inode) spin_lock(&bdev_lock); if (inode->i_bdev) { - if (inode->i_sb != blockdev_superblock) + if (!sb_is_blkdev_sb(inode->i_sb)) bdev = inode->i_bdev; __bd_forget(inode); } -- 1.5.6.3