mm: compaction: simplify the code in __compact_finished

Since commit efe771c760 ("mm, compaction: always finish scanning of a
full pageblock"), compaction will always finish scanning a pageblock.  And
migrate_pfn is assured to align with pageblock_nr_pages when we reach
here.  So we will always return COMPACT_SUCCESS if a suitable fallback is
found due to the below IS_ALIGNED check of migrate_pfn.  Simplify the code
to make this clear and improve the readability.  No functional change
intended.

Link: https://lkml.kernel.org/r/20220418141253.24298-12-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Charan Teja Kalla <charante@codeaurora.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Pintu Kumar <pintu@codeaurora.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Miaohe Lin 2022-04-28 23:16:19 -07:00 committed by akpm
parent cff387d6a2
commit fa599c4498

View File

@ -2134,29 +2134,16 @@ static enum compact_result __compact_finished(struct compact_control *cc)
* other migratetype buddy lists.
*/
if (find_suitable_fallback(area, order, migratetype,
true, &can_steal) != -1) {
/* movable pages are OK in any pageblock */
if (migratetype == MIGRATE_MOVABLE)
return COMPACT_SUCCESS;
true, &can_steal) != -1)
/*
* We are stealing for a non-movable allocation. Make
* sure we finish compacting the current pageblock
* first so it is as free as possible and we won't
* have to steal another one soon. This only applies
* to sync compaction, as async compaction operates
* on pageblocks of the same migratetype.
* Movable pages are OK in any pageblock. If we are
* stealing for a non-movable allocation, make sure
* we finish compacting the current pageblock first
* (which is assured by the above migrate_pfn align
* check) so it is as free as possible and we won't
* have to steal another one soon.
*/
if (cc->mode == MIGRATE_ASYNC ||
IS_ALIGNED(cc->migrate_pfn,
pageblock_nr_pages)) {
return COMPACT_SUCCESS;
}
ret = COMPACT_CONTINUE;
break;
}
return COMPACT_SUCCESS;
}
out: