[PATCHv24 07/16] mm: page_alloc: change fallbacks array handling

Marek Szyprowski
2012-04-03T14:14:29Z

From: Michal Nazarewicz <mina86@mina86.com>

This commit adds a row for MIGRATE_ISOLATE type to the fallbacks array
which was missing from it. It also, changes the array traversal logic
a little making MIGRATE_RESERVE an end marker. The letter change,
removes the implicit MIGRATE_UNMOVABLE from the end of each row which
was read by __rmqueue_fallback() function.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
---
mm/page_alloc.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2c0f68a..8e8cd7e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -875,11 +875,12 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
* This array describes the order lists are fallen back to when
* the free lists for the desirable migrate type are depleted
*/
-static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
+static int fallbacks[MIGRATE_TYPES][3] = {
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
- [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
+ [MIGRATE_RESERVE] = { MIGRATE_RESERVE }, /* Never used */
+ [MIGRATE_ISOLATE] = { MIGRATE_RESERVE }, /* Never used */
};

/*
@@ -974,12 +975,12 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
/* Find the largest possible block of pages in the other list */
for (current_order = MAX_ORDER-1; current_order >= order;
--current_order) {
- for (i = 0; i < MIGRATE_TYPES - 1; i++) {
+ for (i = 0;; i++) {
migratetype = fallbacks[start_migratetype][i];

/* MIGRATE_RESERVE handled later if necessary */
if (migratetype == MIGRATE_RESERVE)
- continue;
+ break;

area = &(zone->free_area[current_order]);
if (list_empty(&area->free_list[migratetype]))
--
1.7.1.569.g6f426