[PATCH 2/2] Ext3: use unlikely to improve the efficiency of the kernel
From: shilong wang <hidden>
Date: 2013-01-12 09:36:19
Also in:
linux-fsdevel
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
From: Wang Shilong <redacted> Because the function 'sb_getblk' seldomly fails to return NULL value,it will be better to use unlikely to check it. Signed-off-by: Wang Shilong <redacted> --- fs/ext3/inode.c | 6 +++--- fs/ext3/resize.c | 6 +++--- fs/ext3/xattr.c | 2 +- 3 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 61bc8bd..7338a76 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c@@ -1083,7 +1083,7 @@ struct buffer_head *ext3_getblk(handle_t*handle, struct inode *inode,
if (!err && buffer_mapped(&dummy)) {
struct buffer_head *bh;
bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
- if (!bh) {
+ if (unlikely(!bh)) {
*errp = -EIO;
goto err;
}@@ -2734,7 +2734,7 @@ static int __ext3_get_inode_loc(struct inode *inode, return -EIO; bh = sb_getblk(inode->i_sb, block); - if (!bh) { + if (unlikely(!bh)) { ext3_error (inode->i_sb, "ext3_get_inode_loc", "unable to read inode block - " "inode=%lu, block="E3FSBLK,
@@ -2788,7 +2788,7 @@ static int __ext3_get_inode_loc(struct inode *inode, bitmap_bh = sb_getblk(inode->i_sb, le32_to_cpu(desc->bg_inode_bitmap)); - if (!bitmap_bh) + if (unlikely(!bitmap_bh)) goto make_io; /*
diff --git a/fs/ext3/resize.c b/fs/ext3/resize.c
index 0f814f3..704e8ce 100644
--- a/fs/ext3/resize.c
+++ b/fs/ext3/resize.c@@ -116,7 +116,7 @@ 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 = ext3_journal_get_write_access(handle, bh))) {
brelse(bh);@@ -234,7 +234,7 @@ static int setup_new_group_blocks(struct super_block *sb, goto exit_bh; gdb = sb_getblk(sb, block); - if (!gdb) { + if (unlikely(!gdb)) { err = -EIO; goto exit_bh; }
@@ -722,7 +722,7 @@ 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; }
diff --git a/fs/ext3/xattr.c b/fs/ext3/xattr.c
index d22ebb7..9f57470 100644
--- a/fs/ext3/xattr.c
+++ b/fs/ext3/xattr.c@@ -813,7 +813,7 @@ inserted: ea_idebug(inode, "creating block %d", block); new_bh = sb_getblk(sb, block); - if (!new_bh) { + if (unlikely(!new_bh)) { getblk_failed: ext3_free_blocks(handle, inode, block, 1); error = -EIO;
--
1.7.7.6