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>

1 files changed, 14 insertions, 15 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2ce5a9ef508b..5607393198df 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -49,11 +49,11 @@ static void f2fs_read_end_io(struct bio *bio, int err)
                 if (--bvec >= bio->bi_io_vec)
                         prefetchw(&bvec->bv_page->flags);
 
-                if (uptodate) {
-                        SetPageUptodate(page);
-                } else {
+                if (unlikely(!uptodate)) {
                         ClearPageUptodate(page);
                         SetPageError(page);
+                } else {
+                        SetPageUptodate(page);
                 }
                 unlock_page(page);
         } while (bvec >= bio->bi_io_vec);
@@ -73,7 +73,7 @@ static void f2fs_write_end_io(struct bio *bio, int err)
                 if (--bvec >= bio->bi_io_vec)
                         prefetchw(&bvec->bv_page->flags);
 
-                if (!uptodate) {
+                if (unlikely(!uptodate)) {
                         SetPageError(page);
                         set_bit(AS_EIO, &page->mapping->flags);
                         set_ckpt_flags(sbi->ckpt, CP_ERROR_FLAG);
@@ -249,7 +249,7 @@ int reserve_new_block(struct dnode_of_data *dn)
 {
         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 
-        if (is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC))
+        if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
                 return -EPERM;
         if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1)))
                 return -ENOSPC;
@@ -424,7 +424,7 @@ struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
                 return ERR_PTR(-ENOENT);
 
         /* By fallocate(), there is no cached page, but with NEW_ADDR */
-        if (dn.data_blkaddr == NEW_ADDR)
+        if (unlikely(dn.data_blkaddr == NEW_ADDR))
                 return ERR_PTR(-EINVAL);
 
         page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
@@ -443,7 +443,7 @@ struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
 
         if (sync) {
                 wait_on_page_locked(page);
-                if (!PageUptodate(page)) {
+                if (unlikely(!PageUptodate(page))) {
                         f2fs_put_page(page, 0);
                         return ERR_PTR(-EIO);
                 }
@@ -477,7 +477,7 @@ repeat:
         }
         f2fs_put_dnode(&dn);
 
-        if (dn.data_blkaddr == NULL_ADDR) {
+        if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
                 f2fs_put_page(page, 1);
                 return ERR_PTR(-ENOENT);
         }
@@ -502,11 +502,11 @@ repeat:
                 return ERR_PTR(err);
 
         lock_page(page);
-        if (!PageUptodate(page)) {
+        if (unlikely(!PageUptodate(page))) {
                 f2fs_put_page(page, 1);
                 return ERR_PTR(-EIO);
         }
-        if (page->mapping != mapping) {
+        if (unlikely(page->mapping != mapping)) {
                 f2fs_put_page(page, 1);
                 goto repeat;
         }
@@ -534,7 +534,6 @@ struct page *get_new_data_page(struct inode *inode,
         err = f2fs_reserve_block(&dn, index);
         if (err)
                 return ERR_PTR(err);
-
 repeat:
         page = grab_cache_page(mapping, index);
         if (!page)
@@ -552,11 +551,11 @@ repeat:
                 if (err)
                         return ERR_PTR(err);
                 lock_page(page);
-                if (!PageUptodate(page)) {
+                if (unlikely(!PageUptodate(page))) {
                         f2fs_put_page(page, 1);
                         return ERR_PTR(-EIO);
                 }
-                if (page->mapping != mapping) {
+                if (unlikely(page->mapping != mapping)) {
                         f2fs_put_page(page, 1);
                         goto repeat;
                 }
@@ -841,11 +840,11 @@ repeat:
                 if (err)
                         return err;
                 lock_page(page);
-                if (!PageUptodate(page)) {
+                if (unlikely(!PageUptodate(page))) {
                         f2fs_put_page(page, 1);
                         return -EIO;
                 }
-                if (page->mapping != mapping) {
+                if (unlikely(page->mapping != mapping)) {
                         f2fs_put_page(page, 1);
                         goto repeat;
                 }