likely profiling shows that the following is a miss.
After boot:
[+- ] Type | # True | # False | Function:Filename@Line
+unlikely |     1074|        0  prune_dcache()@:fs/dcache.c@409
After a bonnie++ run:
+unlikely |    66716|    19584  prune_dcache()@:fs/dcache.c@409
So remove it.
Signed-off-by: Hua Zhong <hzhong@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
                cond_resched_lock(&dcache_lock);
 
                tmp = dentry_unused.prev;
-               if (unlikely(sb)) {
+               if (sb) {
                        /* Try to find a dentry for this sb, but don't try
                         * too hard, if they aren't near the tail they will
                         * be moved down again soon