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-rw-r--r--mm/swap.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/mm/swap.c b/mm/swap.c
index c02f93611a8..4aea806d0d4 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -39,6 +39,7 @@ int page_cluster;
static DEFINE_PER_CPU(struct pagevec[NR_LRU_LISTS], lru_add_pvecs);
static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs);
+static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs);
/*
* This path almost never happens for VM activity - pages are normally
@@ -347,6 +348,60 @@ void add_page_to_unevictable_list(struct page *page)
}
/*
+ * If the page can not be invalidated, it is moved to the
+ * inactive list to speed up its reclaim. It is moved to the
+ * head of the list, rather than the tail, to give the flusher
+ * threads some time to write it out, as this is much more
+ * effective than the single-page writeout from reclaim.
+ */
+static void lru_deactivate(struct page *page, struct zone *zone)
+{
+ int lru, file;
+
+ if (!PageLRU(page) || !PageActive(page))
+ return;
+
+ /* Some processes are using the page */
+ if (page_mapped(page))
+ return;
+
+ file = page_is_file_cache(page);
+ lru = page_lru_base_type(page);
+ del_page_from_lru_list(zone, page, lru + LRU_ACTIVE);
+ ClearPageActive(page);
+ ClearPageReferenced(page);
+ add_page_to_lru_list(zone, page, lru);
+ __count_vm_event(PGDEACTIVATE);
+
+ update_page_reclaim_stat(zone, page, file, 0);
+}
+
+static void ____pagevec_lru_deactivate(struct pagevec *pvec)
+{
+ int i;
+ struct zone *zone = NULL;
+
+ for (i = 0; i < pagevec_count(pvec); i++) {
+ struct page *page = pvec->pages[i];
+ struct zone *pagezone = page_zone(page);
+
+ if (pagezone != zone) {
+ if (zone)
+ spin_unlock_irq(&zone->lru_lock);
+ zone = pagezone;
+ spin_lock_irq(&zone->lru_lock);
+ }
+ lru_deactivate(page, zone);
+ }
+ if (zone)
+ spin_unlock_irq(&zone->lru_lock);
+
+ release_pages(pvec->pages, pvec->nr, pvec->cold);
+ pagevec_reinit(pvec);
+}
+
+
+/*
* Drain pages out of the cpu's pagevecs.
* Either "cpu" is the current CPU, and preemption has already been
* disabled; or "cpu" is being hot-unplugged, and is already dead.
@@ -372,6 +427,29 @@ static void drain_cpu_pagevecs(int cpu)
pagevec_move_tail(pvec);
local_irq_restore(flags);
}
+
+ pvec = &per_cpu(lru_deactivate_pvecs, cpu);
+ if (pagevec_count(pvec))
+ ____pagevec_lru_deactivate(pvec);
+}
+
+/**
+ * deactivate_page - forcefully deactivate a page
+ * @page: page to deactivate
+ *
+ * This function hints the VM that @page is a good reclaim candidate,
+ * for example if its invalidation fails due to the page being dirty
+ * or under writeback.
+ */
+void deactivate_page(struct page *page)
+{
+ if (likely(get_page_unless_zero(page))) {
+ struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
+
+ if (!pagevec_add(pvec, page))
+ ____pagevec_lru_deactivate(pvec);
+ put_cpu_var(lru_deactivate_pvecs);
+ }
}
void lru_add_drain(void)