fs/jbd/revoke.c: replace shift loop by ilog2

journal_init_revoke_table is only called with positive hash_size
(JOURNAL_REVOKE_DEFAULT_HASH) so we can replace loop shift by ilog2

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/jbd/revoke.c b/fs/jbd/revoke.c
index 25c713e..8898bbd 100644
--- a/fs/jbd/revoke.c
+++ b/fs/jbd/revoke.c
@@ -231,19 +231,15 @@
 
 static struct jbd_revoke_table_s *journal_init_revoke_table(int hash_size)
 {
-	int shift = 0;
-	int tmp = hash_size;
+	int i;
 	struct jbd_revoke_table_s *table;
 
 	table = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL);
 	if (!table)
 		goto out;
 
-	while((tmp >>= 1UL) != 0UL)
-		shift++;
-
 	table->hash_size = hash_size;
-	table->hash_shift = shift;
+	table->hash_shift = ilog2(hash_size);
 	table->hash_table =
 		kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL);
 	if (!table->hash_table) {
@@ -252,8 +248,8 @@
 		goto out;
 	}
 
-	for (tmp = 0; tmp < hash_size; tmp++)
-		INIT_LIST_HEAD(&table->hash_table[tmp]);
+	for (i = 0; i < hash_size; i++)
+		INIT_LIST_HEAD(&table->hash_table[i]);
 
 out:
 	return table;