1 files changed, 83 insertions, 28 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 99b434b..2624edc 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -553,7 +553,7 @@ void putback_lru_page(struct page *page)
 redo:
 	ClearPageUnevictable(page);
 
-	if (page_evictable(page, NULL)) {
+	if (page_evictable(page)) {
 		/*
 		 * For evictable pages, we can use the cache.
 		 * In event of a race, worst case is we end up with an
@@ -587,7 +587,7 @@ redo:
 	 * page is on unevictable list, it never be freed. To avoid that,
 	 * check after we added it to the list, again.
 	 */
-	if (lru == LRU_UNEVICTABLE && page_evictable(page, NULL)) {
+	if (lru == LRU_UNEVICTABLE && page_evictable(page)) {
 		if (!isolate_lru_page(page)) {
 			put_page(page);
 			goto redo;
@@ -674,8 +674,10 @@ static enum page_references page_check_references(struct page *page,
 static unsigned long shrink_page_list(struct list_head *page_list,
 				      struct zone *zone,
 				      struct scan_control *sc,
+				      enum ttu_flags ttu_flags,
 				      unsigned long *ret_nr_dirty,
-				      unsigned long *ret_nr_writeback)
+				      unsigned long *ret_nr_writeback,
+				      bool force_reclaim)
 {
 	LIST_HEAD(ret_pages);
 	LIST_HEAD(free_pages);
@@ -689,10 +691,10 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 
 	mem_cgroup_uncharge_start();
 	while (!list_empty(page_list)) {
-		enum page_references references;
 		struct address_space *mapping;
 		struct page *page;
 		int may_enter_fs;
+		enum page_references references = PAGEREF_RECLAIM_CLEAN;
 
 		cond_resched();
 
@@ -707,7 +709,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 
 		sc->nr_scanned++;
 
-		if (unlikely(!page_evictable(page, NULL)))
+		if (unlikely(!page_evictable(page)))
 			goto cull_mlocked;
 
 		if (!sc->may_unmap && page_mapped(page))
@@ -758,7 +760,9 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			wait_on_page_writeback(page);
 		}
 
-		references = page_check_references(page, sc);
+		if (!force_reclaim)
+			references = page_check_references(page, sc);
+
 		switch (references) {
 		case PAGEREF_ACTIVATE:
 			goto activate_locked;
@@ -788,7 +792,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 		 * processes. Try to unmap it here.
 		 */
 		if (page_mapped(page) && mapping) {
-			switch (try_to_unmap(page, TTU_UNMAP)) {
+			switch (try_to_unmap(page, ttu_flags)) {
 			case SWAP_FAIL:
 				goto activate_locked;
 			case SWAP_AGAIN:
@@ -960,6 +964,33 @@ keep:
 	return nr_reclaimed;
 }
 
+unsigned long reclaim_clean_pages_from_list(struct zone *zone,
+					    struct list_head *page_list)
+{
+	struct scan_control sc = {
+		.gfp_mask = GFP_KERNEL,
+		.priority = DEF_PRIORITY,
+		.may_unmap = 1,
+	};
+	unsigned long ret, dummy1, dummy2;
+	struct page *page, *next;
+	LIST_HEAD(clean_pages);
+
+	list_for_each_entry_safe(page, next, page_list, lru) {
+		if (page_is_file_cache(page) && !PageDirty(page)) {
+			ClearPageActive(page);
+			list_move(&page->lru, &clean_pages);
+		}
+	}
+
+	ret = shrink_page_list(&clean_pages, zone, &sc,
+				TTU_UNMAP|TTU_IGNORE_ACCESS,
+				&dummy1, &dummy2, true);
+	list_splice(&clean_pages, page_list);
+	__mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret);
+	return ret;
+}
+
 /*
  * Attempt to remove the specified page from its LRU.  Only take this page
  * if it is of the appropriate PageActive status.  Pages which are being
@@ -978,8 +1009,8 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode)
 	if (!PageLRU(page))
 		return ret;
 
-	/* Do not give back unevictable pages for compaction */
-	if (PageUnevictable(page))
+	/* Compaction should not handle unevictable pages but CMA can do so */
+	if (PageUnevictable(page) && !(mode & ISOLATE_UNEVICTABLE))
 		return ret;
 
 	ret = -EBUSY;
@@ -1186,7 +1217,7 @@ putback_inactive_pages(struct lruvec *lruvec, struct list_head *page_list)
 
 		VM_BUG_ON(PageLRU(page));
 		list_del(&page->lru);
-		if (unlikely(!page_evictable(page, NULL))) {
+		if (unlikely(!page_evictable(page))) {
 			spin_unlock_irq(&zone->lru_lock);
 			putback_lru_page(page);
 			spin_lock_irq(&zone->lru_lock);
@@ -1278,8 +1309,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 	if (nr_taken == 0)
 		return 0;
 
-	nr_reclaimed = shrink_page_list(&page_list, zone, sc,
-						&nr_dirty, &nr_writeback);
+	nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP,
+					&nr_dirty, &nr_writeback, false);
 
 	spin_lock_irq(&zone->lru_lock);
 
@@ -1439,7 +1470,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
 		page = lru_to_page(&l_hold);
 		list_del(&page->lru);
 
-		if (unlikely(!page_evictable(page, NULL))) {
+		if (unlikely(!page_evictable(page))) {
 			putback_lru_page(page);
 			continue;
 		}
@@ -1729,6 +1760,28 @@ static bool in_reclaim_compaction(struct scan_control *sc)
 	return false;
 }
 
+#ifdef CONFIG_COMPACTION
+/*
+ * If compaction is deferred for sc->order then scale the number of pages
+ * reclaimed based on the number of consecutive allocation failures
+ */
+static unsigned long scale_for_compaction(unsigned long pages_for_compaction,
+			struct lruvec *lruvec, struct scan_control *sc)
+{
+	struct zone *zone = lruvec_zone(lruvec);
+
+	if (zone->compact_order_failed <= sc->order)
+		pages_for_compaction <<= zone->compact_defer_shift;
+	return pages_for_compaction;
+}
+#else
+static unsigned long scale_for_compaction(unsigned long pages_for_compaction,
+			struct lruvec *lruvec, struct scan_control *sc)
+{
+	return pages_for_compaction;
+}
+#endif
+
 /*
  * Reclaim/compaction is used for high-order allocation requests. It reclaims
  * order-0 pages before compacting the zone. should_continue_reclaim() returns
@@ -1776,6 +1829,9 @@ static inline bool should_continue_reclaim(struct lruvec *lruvec,
 	 * inactive lists are large enough, continue reclaiming
 	 */
 	pages_for_compaction = (2UL << sc->order);
+
+	pages_for_compaction = scale_for_compaction(pages_for_compaction,
+						    lruvec, sc);
 	inactive_lru_pages = get_lru_size(lruvec, LRU_INACTIVE_FILE);
 	if (nr_swap_pages > 0)
 		inactive_lru_pages += get_lru_size(lruvec, LRU_INACTIVE_ANON);
@@ -2839,6 +2895,14 @@ static void kswapd_try_to_sleep(pg_data_t *pgdat, int order, int classzone_idx)
 		 */
 		set_pgdat_percpu_threshold(pgdat, calculate_normal_threshold);
 
+		/*
+		 * Compaction records what page blocks it recently failed to
+		 * isolate pages from and skips them in the future scanning.
+		 * When kswapd is going to sleep, it is reasonable to assume
+		 * that pages and compaction may succeed so reset the cache.
+		 */
+		reset_isolation_suitable(pgdat);
+
 		if (!kthread_should_stop())
 			schedule();
 
@@ -3101,9 +3165,9 @@ int kswapd_run(int nid)
 	if (IS_ERR(pgdat->kswapd)) {
 		/* failure at boot is fatal */
 		BUG_ON(system_state == SYSTEM_BOOTING);
-		printk("Failed to start kswapd on node %d\n",nid);
 		pgdat->kswapd = NULL;
-		ret = -1;
+		pr_err("Failed to start kswapd on node %d\n", nid);
+		ret = PTR_ERR(pgdat->kswapd);
 	}
 	return ret;
 }
@@ -3350,27 +3414,18 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 /*
  * page_evictable - test whether a page is evictable
  * @page: the page to test
- * @vma: the VMA in which the page is or will be mapped, may be NULL
  *
  * Test whether page is evictable--i.e., should be placed on active/inactive
- * lists vs unevictable list.  The vma argument is !NULL when called from the
- * fault path to determine how to instantate a new page.
+ * lists vs unevictable list.
  *
  * Reasons page might not be evictable:
  * (1) page's mapping marked unevictable
  * (2) page is part of an mlocked VMA
  *
  */
-int page_evictable(struct page *page, struct vm_area_struct *vma)
+int page_evictable(struct page *page)
 {
-
-	if (mapping_unevictable(page_mapping(page)))
-		return 0;
-
-	if (PageMlocked(page) || (vma && mlocked_vma_newpage(vma, page)))
-		return 0;
-
-	return 1;
+	return !mapping_unevictable(page_mapping(page)) && !PageMlocked(page);
 }
 
 #ifdef CONFIG_SHMEM
@@ -3408,7 +3463,7 @@ void check_move_unevictable_pages(struct page **pages, int nr_pages)
 		if (!PageLRU(page) || !PageUnevictable(page))
 			continue;
 
-		if (page_evictable(page, NULL)) {
+		if (page_evictable(page)) {
 			enum lru_list lru = page_lru_base_type(page);
 
 			VM_BUG_ON(PageActive(page));