f2fs: add unlikely() macro for compiler more aggressively
This patch adds unlikely() macro into the most of codes.
The basic rule is to add that when:
- checking unusual errors,
- checking page mappings,
- and the other unlikely conditions.
Change log from v1:
- Don't add unlikely for the NULL test and error test: advised by Andi Kleen.
Cc: Chao Yu <chao2.yu@samsung.com>
Cc: Andi Kleen <andi@firstfloor.org>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 22b07c3..68df44a 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -626,7 +626,7 @@
struct f2fs_sb_info *sbi = F2FS_SB(sb);
struct inode *inode;
- if (ino < F2FS_ROOT_INO(sbi))
+ if (unlikely(ino < F2FS_ROOT_INO(sbi)))
return ERR_PTR(-ESTALE);
/*
@@ -637,7 +637,7 @@
inode = f2fs_iget(sb, ino);
if (IS_ERR(inode))
return ERR_CAST(inode);
- if (generation && inode->i_generation != generation) {
+ if (unlikely(generation && inode->i_generation != generation)) {
/* we didn't find the right inode.. */
iput(inode);
return ERR_PTR(-ESTALE);
@@ -740,10 +740,10 @@
fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
- if (fsmeta >= total)
+ if (unlikely(fsmeta >= total))
return 1;
- if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
+ if (unlikely(is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) {
f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
return 1;
}
@@ -808,7 +808,7 @@
brelse(*raw_super_buf);
f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
"in %dth superblock", block + 1);
- if(block == 0) {
+ if (block == 0) {
block++;
goto retry;
} else {
@@ -834,7 +834,7 @@
return -ENOMEM;
/* set a block size */
- if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
+ if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
goto free_sbi;
}
@@ -1066,7 +1066,7 @@
{
f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
sizeof(struct f2fs_inode_info), NULL);
- if (f2fs_inode_cachep == NULL)
+ if (!f2fs_inode_cachep)
return -ENOMEM;
return 0;
}