cma: redirect page allocation to CMA
CMA pages are designed to be used as fallback for movable allocations
and cannot be used for non-movable allocations. If CMA pages are
utilized poorly, non-movable allocations may end up getting starved if
all regular movable pages are allocated and the only pages left are
CMA. Always using CMA pages first creates unacceptable performance
problems. As a midway alternative, use CMA pages for certain
userspace allocations. The userspace pages can be migrated or dropped
quickly which giving decent utilization.
Change-Id: I6165dda01b705309eebabc6dfa67146b7a95c174
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Heesub Shin <heesub.shin@samsung.com
[lauraa@codeaurora.org: Missing CONFIG_CMA guards, add commit text]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
[lmark@codeaurora.org: resolve conflicts relating to
MIGRATE_HIGHATOMIC and some other trivial merge conflicts]
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 27ddaae..7eb13a2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2209,11 +2209,26 @@
page = __rmqueue_smallest(zone, order, migratetype);
if (unlikely(!page)) {
- if (migratetype == MIGRATE_MOVABLE)
- page = __rmqueue_cma_fallback(zone, order);
+ page = __rmqueue_fallback(zone, order, migratetype);
+ }
- if (!page)
- page = __rmqueue_fallback(zone, order, migratetype);
+ trace_mm_page_alloc_zone_locked(page, order, migratetype);
+ return page;
+}
+
+static struct page *__rmqueue_cma(struct zone *zone, unsigned int order,
+ int migratetype)
+{
+ struct page *page = 0;
+#ifdef CONFIG_CMA
+ if (migratetype == MIGRATE_MOVABLE && !zone->cma_alloc)
+ page = __rmqueue_cma_fallback(zone, order);
+ else
+#endif
+ page = __rmqueue_smallest(zone, order, migratetype);
+
+ if (unlikely(!page)) {
+ page = __rmqueue_fallback(zone, order, migratetype);
}
trace_mm_page_alloc_zone_locked(page, order, migratetype);
@@ -2227,13 +2242,17 @@
*/
static int rmqueue_bulk(struct zone *zone, unsigned int order,
unsigned long count, struct list_head *list,
- int migratetype, bool cold)
+ int migratetype, bool cold, int cma)
{
int i, alloced = 0;
spin_lock(&zone->lock);
for (i = 0; i < count; ++i) {
- struct page *page = __rmqueue(zone, order, migratetype);
+ struct page *page;
+ if (cma)
+ page = __rmqueue_cma(zone, order, migratetype);
+ else
+ page = __rmqueue(zone, order, migratetype);
if (unlikely(page == NULL))
break;
@@ -2645,7 +2664,8 @@
if (list_empty(list)) {
pcp->count += rmqueue_bulk(zone, 0,
pcp->batch, list,
- migratetype, cold);
+ migratetype, cold,
+ gfp_flags & __GFP_CMA);
if (unlikely(list_empty(list)))
goto failed;
}
@@ -2674,8 +2694,12 @@
if (page)
trace_mm_page_alloc_zone_locked(page, order, migratetype);
}
- if (!page)
- page = __rmqueue(zone, order, migratetype);
+ if (!page) {
+ if (gfp_flags & __GFP_CMA)
+ page = __rmqueue_cma(zone, order, migratetype);
+ else
+ page = __rmqueue(zone, order, migratetype);
+ }
} while (page && check_new_pages(page, order));
spin_unlock(&zone->lock);
if (!page)
@@ -7311,6 +7335,7 @@
if (ret)
return ret;
+ cc.zone->cma_alloc = 1;
/*
* In case of -EBUSY, we'd like to know which page causes problem.
* So, just fall through. We will check it in test_pages_isolated().
@@ -7386,6 +7411,7 @@
done:
undo_isolate_page_range(pfn_max_align_down(start),
pfn_max_align_up(end), migratetype);
+ cc.zone->cma_alloc = 0;
return ret;
}