To spread dirty page, nodes are checked whether
it reached the dirty limit using the expensive
node_dirty_ok(). To reduce the number of calling
node_dirty_ok(), last node that hit the dirty
limit is cached.
Instead of caching the node, caching both node
and it's result of node_dirty_ok() can reduce
the number of calling node_dirty_ok() more than
before.
Signed-off-by: Wonhyuk Yang <vvghjk1234@xxxxxxxxx>
---
mm/page_alloc.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0e42038382c1..aba62cf31a0e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4068,7 +4068,8 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
{
struct zoneref *z;
struct zone *zone;
- struct pglist_data *last_pgdat_dirty_limit = NULL;
+ struct pglist_data *last_pgdat = NULL;
+ bool last_pgdat_dirty_limit = false;
bool no_fallback;
retry:
@@ -4107,13 +4108,13 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
* dirty-throttling and the flusher threads.
*/
if (ac->spread_dirty_pages) {
- if (last_pgdat_dirty_limit == zone->zone_pgdat)
- continue;
+ if (last_pgdat != zone->zone_pgdat) {
+ last_pgdat = zone->zone_pgdat;
+ last_pgdat_dirty_limit = node_dirty_ok(zone->zone_pgdat);
+ }
- if (!node_dirty_ok(zone->zone_pgdat)) {
- last_pgdat_dirty_limit = zone->zone_pgdat;
+ if (!last_pgdat_dirty_limit)
continue;
- }
}
if (no_fallback && nr_online_nodes > 1 &&
--
2.30.2
