Unionfs: add un/likely conditionals on mmap ops

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/unionfs/mmap.c b/fs/unionfs/mmap.c
index 37af97927a79cdef36639eccb49cd93f145fccfb..1cea0753754c7adeb79bfe9924750655c01e730c 100644 (file)
--- a/fs/unionfs/mmap.c
+++ b/fs/unionfs/mmap.c
@@ -84,7 +84,7 @@ static int unionfs_writepage(struct page *page, struct writeback_control *wbc)
         * resort to RAIF's page pointer flipping trick.)
         */
        lower_page = find_lock_page(lower_inode->i_mapping, page->index);
-       if (!lower_page) {
+       if (unlikely(!lower_page)) {
                err = AOP_WRITEPAGE_ACTIVATE;
                set_page_dirty(page);
                goto out;
@@ -102,7 +102,7 @@ static int unionfs_writepage(struct page *page, struct writeback_control *wbc)
        BUG_ON(!lower_inode->i_mapping->a_ops->writepage);
 
        /* workaround for some lower file systems: see big comment on top */
-       if (wbc->for_writepages && !wbc->fs_private)
+       if (unlikely(wbc->for_writepages && !wbc->fs_private))
                wbc->for_writepages = 0;
 
        /* call lower writepage (expects locked page) */
@@ -111,12 +111,12 @@ static int unionfs_writepage(struct page *page, struct writeback_control *wbc)
        wbc->for_writepages = saved_for_writepages; /* restore value */
 
        /* b/c find_lock_page locked it and ->writepage unlocks on success */
-       if (err)
+       if (unlikely(err))
                unlock_page(lower_page);
        /* b/c grab_cache_page increased refcnt */
        page_cache_release(lower_page);
 
-       if (err < 0) {
+       if (unlikely(err < 0)) {
                ClearPageUptodate(page);
                goto out;
        }
@@ -160,7 +160,7 @@ static int unionfs_do_readpage(struct file *file, struct page *page)
        char *page_data = NULL;
        loff_t offset;
 
-       if (!UNIONFS_F(file)) {
+       if (unlikely(!UNIONFS_F(file))) {
                err = -ENOENT;
                goto out;
        }
@@ -189,7 +189,7 @@ static int unionfs_do_readpage(struct file *file, struct page *page)
 
        kunmap(page);
 
-       if (err < 0)
+       if (unlikely(err < 0))
                goto out;
        err = 0;
 
@@ -199,7 +199,7 @@ static int unionfs_do_readpage(struct file *file, struct page *page)
        flush_dcache_page(page);
 
 out:
-       if (err == 0)
+       if (likely(err == 0))
                SetPageUptodate(page);
        else
                ClearPageUptodate(page);
@@ -212,13 +212,13 @@ static int unionfs_readpage(struct file *file, struct page *page)
        int err;
 
        unionfs_read_lock(file->f_path.dentry->d_sb);
-       if ((err = unionfs_file_revalidate(file, false)))
+       if (unlikely((err = unionfs_file_revalidate(file, false))))
                goto out;
        unionfs_check_file(file);
 
        err = unionfs_do_readpage(file, page);
 
-       if (!err) {
+       if (likely(!err)) {
                touch_atime(unionfs_lower_mnt(file->f_path.dentry),
                            unionfs_lower_dentry(file->f_path.dentry));
                unionfs_copy_attr_times(file->f_path.dentry->d_inode);
@@ -276,14 +276,14 @@ static int unionfs_commit_write(struct file *file, struct page *page,
        BUG_ON(file == NULL);
 
        unionfs_read_lock(file->f_path.dentry->d_sb);
-       if ((err = unionfs_file_revalidate(file, true)))
+       if (unlikely((err = unionfs_file_revalidate(file, true))))
                goto out;
        unionfs_check_file(file);
 
        inode = page->mapping->host;
        lower_inode = unionfs_lower_inode(inode);
 
-       if (UNIONFS_F(file) != NULL)
+       if (likely(UNIONFS_F(file) != NULL))
                lower_file = unionfs_lower_file(file);
 
        /* FIXME: is this assertion right here? */
@@ -307,7 +307,7 @@ static int unionfs_commit_write(struct file *file, struct page *page,
 
        kunmap(page);
 
-       if (err < 0)
+       if (unlikely(err < 0))
                goto out;
 
        inode->i_blocks = lower_inode->i_blocks;
@@ -320,7 +320,7 @@ static int unionfs_commit_write(struct file *file, struct page *page,
        mark_inode_dirty_sync(inode);
 
 out:
-       if (err < 0)
+       if (unlikely(err < 0))
                ClearPageUptodate(page);
 
        unionfs_read_unlock(file->f_path.dentry->d_sb);
@@ -347,7 +347,7 @@ static void unionfs_sync_page(struct page *page)
         * do is ensure that pending I/O gets done.
         */
        lower_page = find_lock_page(lower_inode->i_mapping, page->index);
-       if (!lower_page) {
+       if (unlikely(!lower_page)) {
                printk(KERN_DEBUG "unionfs: find_lock_page failed\n");
                goto out;
        }