mballoc: remove unncessary mb_find_buddy()

In __mb_check_buddy(), look at the bellowed code,

 591         fstart = -1;
 592         buddy = mb_find_buddy(e4b, 0, &max);
 593         for (i = 0; i < max; i++) {
 594                 if (!mb_test_bit(i, buddy)) {
 595                         MB_CHECK_ASSERT(i >= e4b->bd_info->bb_first_free);
 596                         if (fstart == -1) {
 597                                 fragments++;
 598                                 fstart = i;
 599                         }
 600                         continue;
 601                 }
 602                 fstart = -1;
 603                 /* check used bits only */
 604                 for (j = 0; j < e4b->bd_blkbits + 1; j++) {
 605                         buddy2 = mb_find_buddy(e4b, j, &max2);
 606                         k = i >> j;
 607                         MB_CHECK_ASSERT(k < max2);
 608                         MB_CHECK_ASSERT(mb_test_bit(k, buddy2));
 609                 }
 610         }
 611         MB_CHECK_ASSERT(!EXT4_MB_GRP_NEED_INIT(e4b->bd_info));
 612         MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);

613
614 grp = ext4_get_group_info(sb, e4b->bd_group);
615 buddy = mb_find_buddy(e4b, 0, &max);

On line 592, buddy is fetched by mb_find_buddy() with order 0, between line 593 to line 615, buddy is not changed, therefore there is no need to fetch buddy again from mb_find_buddy() with order 0 again.

We can safely remove the second mb_find_buddy() on line 615.

---
 fs/ext4/mballoc.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

index d5b372c..458dce0 100644
@@ -612,7 +612,6 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
 	MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);
 
 	grp = ext4_get_group_info(sb, e4b->bd_group);
-	buddy = mb_find_buddy(e4b, 0, &max);
 	list_for_each(cur, &grp->bb_prealloc_list) {
 		ext4_group_t groupnr;
 		struct ext4_prealloc_space *pa;

1.7.3.4

Added to the ext4 patch queue, thanks!!

- Ted