f2fs: add unlikely() macro for compiler optimization

As we know, some of our branch condition will rarely be true. So we could add
'unlikely' to let compiler optimize these code, by this way we could drop
unneeded 'jump' assemble code to improve performance.

change log:
 o add *unlikely* as many as possible across the whole source files at once
   suggested by Jaegeuk Kim.

Suggested-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

1 files changed, 8 insertions, 8 deletions

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 099f06f84e29..2e41636be476 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -94,7 +94,7 @@ static void ra_nat_pages(struct f2fs_sb_info *sbi, int nid)
         int i;
 
         for (i = 0; i < FREE_NID_PAGES; i++, nid += NAT_ENTRY_PER_BLOCK) {
-                if (nid >= nm_i->max_nid)
+                if (unlikely(nid >= nm_i->max_nid))
                         nid = 0;
                 index = current_nat_addr(sbi, nid);
 
@@ -1160,7 +1160,7 @@ int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
                         struct page *page = pvec.pages[i];
 
                         /* until radix tree lookup accepts end_index */
-                        if (page->index > end)
+                        if (unlikely(page->index > end))
                                 continue;
 
                         if (ino && ino_of_node(page) == ino) {
@@ -1190,7 +1190,7 @@ static int f2fs_write_node_page(struct page *page,
         block_t new_addr;
         struct node_info ni;
 
-        if (sbi->por_doing)
+        if (unlikely(sbi->por_doing))
                 goto redirty_out;
 
         wait_on_page_writeback(page);
@@ -1326,7 +1326,7 @@ static int add_free_nid(struct f2fs_nm_info *nm_i, nid_t nid, bool build)
                 return -1;
 
         /* 0 nid should not be used */
-        if (nid == 0)
+        if (unlikely(nid == 0))
                 return 0;
 
         if (build) {
@@ -1379,7 +1379,7 @@ static void scan_nat_page(struct f2fs_nm_info *nm_i,
 
         for (; i < NAT_ENTRY_PER_BLOCK; i++, start_nid++) {
 
-                if (start_nid >= nm_i->max_nid)
+                if (unlikely(start_nid >= nm_i->max_nid))
                         break;
 
                 blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr);
@@ -1413,7 +1413,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi)
                 f2fs_put_page(page, 1);
 
                 nid += (NAT_ENTRY_PER_BLOCK - (nid % NAT_ENTRY_PER_BLOCK));
-                if (nid >= nm_i->max_nid)
+                if (unlikely(nid >= nm_i->max_nid))
                         nid = 0;
 
                 if (i++ == FREE_NID_PAGES)
@@ -1447,7 +1447,7 @@ bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid)
         struct free_nid *i = NULL;
         struct list_head *this;
 retry:
-        if (sbi->total_valid_node_count + 1 >= nm_i->max_nid)
+        if (unlikely(sbi->total_valid_node_count + 1 >= nm_i->max_nid))
                 return false;
 
         spin_lock(&nm_i->free_nid_list_lock);
@@ -1557,7 +1557,7 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
         new_ni = old_ni;
         new_ni.ino = ino;
 
-        if (!inc_valid_node_count(sbi, NULL))
+        if (unlikely(!inc_valid_node_count(sbi, NULL)))
                 WARN_ON(1);
         set_node_addr(sbi, &new_ni, NEW_ADDR);
         inc_valid_inode_count(sbi);