The patch titled
Subject: mm/cma: change fallback behaviour for CMA freepage
has been removed from the -mm tree. Its filename was
mm-cma-change-fallback-behaviour-for-cma-freepage.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Subject: mm/cma: change fallback behaviour for CMA freepage
Freepage with MIGRATE_CMA can be used only for MIGRATE_MOVABLE and they
should not be expanded to other migratetype buddy list to protect them
from unmovable/reclaimable allocation. Implementing these requirements in
__rmqueue_fallback(), that is, finding largest possible block of freepage
has bad effect that high order freepage with MIGRATE_CMA are broken
continually although there are suitable order CMA freepage. Reason is
that they are not be expanded to other migratetype buddy list and next
__rmqueue_fallback() invocation try to finds another largest block of
freepage and break it again. So, MIGRATE_CMA fallback should be handled
separately. This patch introduces __rmqueue_cma_fallback(), that just
wrapper of __rmqueue_smallest() and call it before __rmqueue_fallback() if
migratetype == MIGRATE_MOVABLE.
This results in unintended behaviour change that MIGRATE_CMA freepage is
always used first rather than other migratetype as movable allocation's
fallback. But, as already mentioned above, MIGRATE_CMA can be used only
for MIGRATE_MOVABLE, so it is better to use MIGRATE_CMA freepage first as
much as possible. Otherwise, we needlessly take up precious freepages
with other migratetype and increase chance of fragmentation.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 36 +++++++++++++++++++-----------------
1 file changed, 19 insertions(+), 17 deletions(-)
diff -puN mm/page_alloc.c~mm-cma-change-fallback-behaviour-for-cma-freepage mm/page_alloc.c
--- a/mm/page_alloc.c~mm-cma-change-fallback-behaviour-for-cma-freepage
+++ a/mm/page_alloc.c
@@ -1032,11 +1032,9 @@ struct page *__rmqueue_smallest(struct z
static int fallbacks[MIGRATE_TYPES][4] = {
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
+ [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
#ifdef CONFIG_CMA
- [MIGRATE_MOVABLE] = { MIGRATE_CMA, MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
[MIGRATE_CMA] = { MIGRATE_RESERVE }, /* Never used */
-#else
- [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
#endif
[MIGRATE_RESERVE] = { MIGRATE_RESERVE }, /* Never used */
#ifdef CONFIG_MEMORY_ISOLATION
@@ -1044,6 +1042,17 @@ static int fallbacks[MIGRATE_TYPES][4] =
#endif
};
+#ifdef CONFIG_CMA
+static struct page *__rmqueue_cma_fallback(struct zone *zone,
+ unsigned int order)
+{
+ return __rmqueue_smallest(zone, order, MIGRATE_CMA);
+}
+#else
+static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
+ unsigned int order) { return NULL; }
+#endif
+
/*
* Move the free pages in a range to the free lists of the requested type.
* Note that start_page and end_pages are not aligned on a pageblock
@@ -1195,19 +1204,8 @@ __rmqueue_fallback(struct zone *zone, un
struct page, lru);
area->nr_free--;
- if (!is_migrate_cma(migratetype)) {
- try_to_steal_freepages(zone, page,
- start_migratetype,
- migratetype);
- } else {
- /*
- * When borrowing from MIGRATE_CMA, we need to
- * release the excess buddy pages to CMA
- * itself, and we do not try to steal extra
- * free pages.
- */
- buddy_type = migratetype;
- }
+ try_to_steal_freepages(zone, page, start_migratetype,
+ migratetype);
/* Remove the page from the freelists */
list_del(&page->lru);
@@ -1249,7 +1247,11 @@ retry_reserve:
page = __rmqueue_smallest(zone, order, migratetype);
if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
- page = __rmqueue_fallback(zone, order, migratetype);
+ if (migratetype == MIGRATE_MOVABLE)
+ page = __rmqueue_cma_fallback(zone, order);
+
+ if (!page)
+ page = __rmqueue_fallback(zone, order, migratetype);
/*
* Use MIGRATE_RESERVE rather than fail an allocation. goto
_
Patches currently in -mm which might be from iamjoonsoo.kim@xxxxxxx are
origin.patch
slab-infrastructure-for-bulk-object-allocation-and-freeing-v3.patch
slub-bulk-alloc-extract-objects-from-the-per-cpu-slab.patch
slub-bulk-allocation-from-per-cpu-partial-pages.patch
slub-bulk-allocation-from-per-cpu-partial-pages-fix.patch
page-flags-define-behavior-slb-related-flags-on-compound-pages.patch
mm-compaction-reset-compaction-scanner-positions.patch
hugetlbfs-add-minimum-size-tracking-fields-to-subpool-structure.patch
hugetlbfs-add-minimum-size-accounting-to-subpools.patch
hugetlbfs-accept-subpool-min_size-mount-option-and-setup-accordingly.patch
hugetlbfs-document-min_size-mount-option-and-cleanup.patch
mm-vmalloc-fix-possible-exhaustion-of-vmalloc-space-caused-by-vm_map_ram-allocator.patch
mm-vmalloc-occupy-newly-allocated-vmap-block-just-after-allocation.patch
mm-vmalloc-get-rid-of-dirty-bitmap-inside-vmap_block-structure.patch
mm-cma-add-trace-events-for-cma-allocations-and-freeings.patch
mm-cma-add-trace-events-for-cma-allocations-and-freeings-fix.patch
mm-cma-add-functions-to-get-region-pages-counters.patch
mm-cma-add-functions-to-get-region-pages-counters-fix.patch
mm-cma-add-functions-to-get-region-pages-counters-fix-2.patch
mm-cma-add-functions-to-get-region-pages-counters-fix-3.patch
mm-cma_debugc-remove-blank-lines-before-define_simple_attribute.patch
zsmalloc-decouple-handle-and-object.patch
zsmalloc-factor-out-obj_.patch
zsmalloc-support-compaction.patch
zsmalloc-adjust-zs_almost_full.patch
zram-support-compaction.patch
zsmalloc-record-handle-in-page-private-for-huge-object.patch
zsmalloc-add-fullness-into-stat.patch
zsmalloc-zsmalloc-documentation.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
