summaryrefslogtreecommitdiffstats
path: root/mm/vmscan.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/vmscan.c')
-rw-r--r--mm/vmscan.c52
1 files changed, 45 insertions, 7 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 6be2068f61c8..1024979d6589 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1212,6 +1212,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
unsigned long pgscanned;
unsigned long vm_flags;
LIST_HEAD(l_hold); /* The pages which were snipped off */
+ LIST_HEAD(l_active);
LIST_HEAD(l_inactive);
struct page *page;
struct pagevec pvec;
@@ -1251,28 +1252,42 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
/* page_referenced clears PageReferenced */
if (page_mapping_inuse(page) &&
- page_referenced(page, 0, sc->mem_cgroup, &vm_flags))
+ page_referenced(page, 0, sc->mem_cgroup, &vm_flags)) {
pgmoved++;
+ /*
+ * Identify referenced, file-backed active pages and
+ * give them one more trip around the active list. So
+ * that executable code get better chances to stay in
+ * memory under moderate memory pressure. Anon pages
+ * are not likely to be evicted by use-once streaming
+ * IO, plus JVM can create lots of anon VM_EXEC pages,
+ * so we ignore them here.
+ */
+ if ((vm_flags & VM_EXEC) && !PageAnon(page)) {
+ list_add(&page->lru, &l_active);
+ continue;
+ }
+ }
list_add(&page->lru, &l_inactive);
}
/*
- * Move the pages to the [file or anon] inactive list.
+ * Move pages back to the lru list.
*/
pagevec_init(&pvec, 1);
- lru = LRU_BASE + file * LRU_FILE;
spin_lock_irq(&zone->lru_lock);
/*
- * Count referenced pages from currently used mappings as
- * rotated, even though they are moved to the inactive list.
- * This helps balance scan pressure between file and anonymous
- * pages in get_scan_ratio.
+ * Count referenced pages from currently used mappings as rotated,
+ * even though only some of them are actually re-activated. This
+ * helps balance scan pressure between file and anonymous pages in
+ * get_scan_ratio.
*/
reclaim_stat->recent_rotated[!!file] += pgmoved;
pgmoved = 0; /* count pages moved to inactive list */
+ lru = LRU_BASE + file * LRU_FILE;
while (!list_empty(&l_inactive)) {
page = lru_to_page(&l_inactive);
prefetchw_prev_lru_page(page, &l_inactive, flags);
@@ -1295,6 +1310,29 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
__mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved);
__count_zone_vm_events(PGREFILL, zone, pgscanned);
__count_vm_events(PGDEACTIVATE, pgmoved);
+
+ pgmoved = 0; /* count pages moved back to active list */
+ lru = LRU_ACTIVE + file * LRU_FILE;
+ while (!list_empty(&l_active)) {
+ page = lru_to_page(&l_active);
+ prefetchw_prev_lru_page(page, &l_active, flags);
+ VM_BUG_ON(PageLRU(page));
+ SetPageLRU(page);
+ VM_BUG_ON(!PageActive(page));
+
+ list_move(&page->lru, &zone->lru[lru].list);
+ mem_cgroup_add_lru_list(page, lru);
+ pgmoved++;
+ if (!pagevec_add(&pvec, page)) {
+ spin_unlock_irq(&zone->lru_lock);
+ if (buffer_heads_over_limit)
+ pagevec_strip(&pvec);
+ __pagevec_release(&pvec);
+ spin_lock_irq(&zone->lru_lock);
+ }
+ }
+ __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved);
+
spin_unlock_irq(&zone->lru_lock);
if (buffer_heads_over_limit)
pagevec_strip(&pvec);