ext4: use unlikely to improve the efficiency of the kernel
Because the function 'sb_getblk' seldomly fails to return NULL
value,it will be better to use 'unlikely' to optimize it.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index 02824dc..05f8d45 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -333,7 +333,7 @@
int err;
bh = sb_getblk(sb, blk);
- if (!bh)
+ if (unlikely(!bh))
return ERR_PTR(-ENOMEM);
if ((err = ext4_journal_get_write_access(handle, bh))) {
brelse(bh);
@@ -410,7 +410,7 @@
return err;
bh = sb_getblk(sb, flex_gd->groups[group].block_bitmap);
- if (!bh)
+ if (unlikely(!bh))
return -ENOMEM;
err = ext4_journal_get_write_access(handle, bh);
@@ -500,7 +500,7 @@
goto out;
gdb = sb_getblk(sb, block);
- if (!gdb) {
+ if (unlikely(!gdb)) {
err = -ENOMEM;
goto out;
}
@@ -1064,7 +1064,7 @@
ext4_bg_has_super(sb, group));
bh = sb_getblk(sb, backup_block);
- if (!bh) {
+ if (unlikely(!bh)) {
err = -ENOMEM;
break;
}
@@ -1168,7 +1168,7 @@
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 (!bh_uptodate_or_lock(bh)) {
if (bh_submit_read(bh) < 0) {