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/node.c b/fs/f2fs/node.c
index 2e41636..6c6ef77 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -750,7 +750,7 @@
if (offset[1] == 0 &&
rn->i.i_nid[offset[0] - NODE_DIR1_BLOCK]) {
lock_page(page);
- if (page->mapping != node_mapping) {
+ if (unlikely(page->mapping != node_mapping)) {
f2fs_put_page(page, 1);
goto restart;
}
@@ -841,14 +841,14 @@
struct page *page;
int err;
- 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 ERR_PTR(-EPERM);
page = grab_cache_page(mapping, dn->nid);
if (!page)
return ERR_PTR(-ENOMEM);
- if (!inc_valid_node_count(sbi, dn->inode)) {
+ if (unlikely(!inc_valid_node_count(sbi, dn->inode))) {
err = -ENOSPC;
goto fail;
}
@@ -898,7 +898,7 @@
get_node_info(sbi, page->index, &ni);
- if (ni.blk_addr == NULL_ADDR) {
+ if (unlikely(ni.blk_addr == NULL_ADDR)) {
f2fs_put_page(page, 1);
return -ENOENT;
}
@@ -953,11 +953,11 @@
goto got_it;
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;
}
@@ -1010,12 +1010,12 @@
blk_finish_plug(&plug);
lock_page(page);
- if (page->mapping != mapping) {
+ if (unlikely(page->mapping != mapping)) {
f2fs_put_page(page, 1);
goto repeat;
}
page_hit:
- if (!PageUptodate(page)) {
+ if (unlikely(!PageUptodate(page))) {
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
@@ -1173,9 +1173,9 @@
cond_resched();
}
- if (test_and_clear_bit(AS_ENOSPC, &mapping->flags))
+ if (unlikely(test_and_clear_bit(AS_ENOSPC, &mapping->flags)))
ret2 = -ENOSPC;
- if (test_and_clear_bit(AS_EIO, &mapping->flags))
+ if (unlikely(test_and_clear_bit(AS_EIO, &mapping->flags)))
ret2 = -EIO;
if (!ret)
ret = ret2;
@@ -1202,7 +1202,7 @@
get_node_info(sbi, nid, &ni);
/* This page is already truncated */
- if (ni.blk_addr == NULL_ADDR) {
+ if (unlikely(ni.blk_addr == NULL_ADDR)) {
dec_page_count(sbi, F2FS_DIRTY_NODES);
unlock_page(page);
return 0;
@@ -1627,14 +1627,14 @@
list_for_each_entry_safe(page, tmp, &page_list, lru) {
lock_page(page);
- if(PageUptodate(page)) {
+ if (unlikely(!PageUptodate(page))) {
+ err = -EIO;
+ } else {
rn = F2FS_NODE(page);
sum_entry->nid = rn->footer.nid;
sum_entry->version = 0;
sum_entry->ofs_in_node = 0;
sum_entry++;
- } else {
- err = -EIO;
}
list_del(&page->lru);