diff --git a/mm/vmscan.c b/mm/vmscan.c
index 961401c..ee4eecc 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -46,9 +46,11 @@
 #include <linux/delayacct.h>
 #include <linux/sysctl.h>
 #include <linux/oom.h>
+#include <linux/pagevec.h>
 #include <linux/prefetch.h>
 #include <linux/printk.h>
 #include <linux/dax.h>
+#include <linux/psi.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -126,6 +128,9 @@
 		unsigned int file_taken;
 		unsigned int taken;
 	} nr;
+
+	/* for recording the reclaimed slab by now */
+	struct reclaim_state reclaim_state;
 };
 
 #ifdef ARCH_HAS_PREFETCH
@@ -166,11 +171,22 @@
  */
 unsigned long vm_total_pages;
 
+static void set_task_reclaim_state(struct task_struct *task,
+				   struct reclaim_state *rs)
+{
+	/* Check for an overwrite */
+	WARN_ON_ONCE(rs && task->reclaim_state);
+
+	/* Check for the nulling of an already-nulled member */
+	WARN_ON_ONCE(!rs && !task->reclaim_state);
+
+	task->reclaim_state = rs;
+}
+
 static LIST_HEAD(shrinker_list);
 static DECLARE_RWSEM(shrinker_rwsem);
 
-#ifdef CONFIG_MEMCG_KMEM
-
+#ifdef CONFIG_MEMCG
 /*
  * We allow subsystems to populate their shrinker-related
  * LRU lists before register_shrinker_prepared() is called
@@ -222,18 +238,7 @@
 	idr_remove(&shrinker_idr, id);
 	up_write(&shrinker_rwsem);
 }
-#else /* CONFIG_MEMCG_KMEM */
-static int prealloc_memcg_shrinker(struct shrinker *shrinker)
-{
-	return 0;
-}
 
-static void unregister_memcg_shrinker(struct shrinker *shrinker)
-{
-}
-#endif /* CONFIG_MEMCG_KMEM */
-
-#ifdef CONFIG_MEMCG
 static bool global_reclaim(struct scan_control *sc)
 {
 	return !sc->target_mem_cgroup;
@@ -288,6 +293,15 @@
 
 }
 #else
+static int prealloc_memcg_shrinker(struct shrinker *shrinker)
+{
+	return 0;
+}
+
+static void unregister_memcg_shrinker(struct shrinker *shrinker)
+{
+}
+
 static bool global_reclaim(struct scan_control *sc)
 {
 	return true;
@@ -337,12 +351,13 @@
  */
 unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx)
 {
-	unsigned long lru_size;
+	unsigned long lru_size = 0;
 	int zid;
 
-	if (!mem_cgroup_disabled())
-		lru_size = mem_cgroup_get_lru_size(lruvec, lru);
-	else
+	if (!mem_cgroup_disabled()) {
+		for (zid = 0; zid < MAX_NR_ZONES; zid++)
+			lru_size += mem_cgroup_get_zone_lru_size(lruvec, lru, zid);
+	} else
 		lru_size = node_page_state(lruvec_pgdat(lruvec), NR_LRU_BASE + lru);
 
 	for (zid = zone_idx + 1; zid < MAX_NR_ZONES; zid++) {
@@ -369,7 +384,7 @@
  */
 int prealloc_shrinker(struct shrinker *shrinker)
 {
-	size_t size = sizeof(*shrinker->nr_deferred);
+	unsigned int size = sizeof(*shrinker->nr_deferred);
 
 	if (shrinker->flags & SHRINKER_NUMA_AWARE)
 		size *= nr_node_ids;
@@ -473,23 +488,22 @@
 	nr = atomic_long_xchg(&shrinker->nr_deferred[nid], 0);
 
 	total_scan = nr;
-	delta = freeable >> priority;
-	delta *= 4;
-	do_div(delta, shrinker->seeks);
-
-	/*
-	 * Make sure we apply some minimal pressure on default priority
-	 * even on small cgroups. Stale objects are not only consuming memory
-	 * by themselves, but can also hold a reference to a dying cgroup,
-	 * preventing it from being reclaimed. A dying cgroup with all
-	 * corresponding structures like per-cpu stats and kmem caches
-	 * can be really big, so it may lead to a significant waste of memory.
-	 */
-	delta = max_t(unsigned long long, delta, min(freeable, batch_size));
+	if (shrinker->seeks) {
+		delta = freeable >> priority;
+		delta *= 4;
+		do_div(delta, shrinker->seeks);
+	} else {
+		/*
+		 * These objects don't require any IO to create. Trim
+		 * them aggressively under memory pressure to keep
+		 * them from causing refetches in the IO caches.
+		 */
+		delta = freeable / 2;
+	}
 
 	total_scan += delta;
 	if (total_scan < 0) {
-		pr_err("shrink_slab: %pF negative objects to delete nr=%ld\n",
+		pr_err("shrink_slab: %pS negative objects to delete nr=%ld\n",
 		       shrinker->scan_objects, total_scan);
 		total_scan = freeable;
 		next_deferred = nr;
@@ -575,7 +589,7 @@
 	return freed;
 }
 
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG
 static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
 			struct mem_cgroup *memcg, int priority)
 {
@@ -583,7 +597,7 @@
 	unsigned long ret, freed = 0;
 	int i;
 
-	if (!memcg_kmem_enabled() || !mem_cgroup_online(memcg))
+	if (!mem_cgroup_online(memcg))
 		return 0;
 
 	if (!down_read_trylock(&shrinker_rwsem))
@@ -609,6 +623,11 @@
 			continue;
 		}
 
+		/* Call non-slab shrinkers even though kmem is disabled */
+		if (!memcg_kmem_enabled() &&
+		    !(shrinker->flags & SHRINKER_NONSLAB))
+			continue;
+
 		ret = do_shrink_slab(&sc, shrinker, priority);
 		if (ret == SHRINK_EMPTY) {
 			clear_bit(i, map->map);
@@ -645,13 +664,13 @@
 	up_read(&shrinker_rwsem);
 	return freed;
 }
-#else /* CONFIG_MEMCG_KMEM */
+#else /* CONFIG_MEMCG */
 static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
 			struct mem_cgroup *memcg, int priority)
 {
 	return 0;
 }
-#endif /* CONFIG_MEMCG_KMEM */
+#endif /* CONFIG_MEMCG */
 
 /**
  * shrink_slab - shrink slab caches
@@ -680,7 +699,14 @@
 	unsigned long ret, freed = 0;
 	struct shrinker *shrinker;
 
-	if (!mem_cgroup_is_root(memcg))
+	/*
+	 * The root memcg might be allocated even though memcg is disabled
+	 * via "cgroup_disable=memory" boot parameter.  This could make
+	 * mem_cgroup_is_root() return false, then just run memcg slab
+	 * shrink, but skip global shrink.  This may result in premature
+	 * oom.
+	 */
+	if (!mem_cgroup_disabled() && !mem_cgroup_is_root(memcg))
 		return shrink_slab_memcg(gfp_mask, nid, memcg, priority);
 
 	if (!down_read_trylock(&shrinker_rwsem))
@@ -741,12 +767,12 @@
 {
 	/*
 	 * A freeable page cache page is referenced only by the caller
-	 * that isolated the page, the page cache radix tree and
-	 * optional buffer heads at page->private.
+	 * that isolated the page, the page cache and optional buffer
+	 * heads at page->private.
 	 */
-	int radix_pins = PageTransHuge(page) && PageSwapCache(page) ?
+	int page_cache_pins = PageTransHuge(page) && PageSwapCache(page) ?
 		HPAGE_PMD_NR : 1;
-	return page_count(page) - page_has_private(page) == 1 + radix_pins;
+	return page_count(page) - page_has_private(page) == 1 + page_cache_pins;
 }
 
 static int may_write_to_inode(struct inode *inode, struct scan_control *sc)
@@ -907,10 +933,7 @@
 	 * Note that if SetPageDirty is always performed via set_page_dirty,
 	 * and thus under the i_pages lock, then this ordering is not required.
 	 */
-	if (unlikely(PageTransHuge(page)) && PageSwapCache(page))
-		refcount = 1 + HPAGE_PMD_NR;
-	else
-		refcount = 2;
+	refcount = 1 + compound_nr(page);
 	if (!page_ref_freeze(page, refcount))
 		goto cannot_free;
 	/* note: atomic_cmpxchg in page_ref_freeze provides the smp_rmb */
@@ -922,7 +945,7 @@
 	if (PageSwapCache(page)) {
 		swp_entry_t swap = { .val = page_private(page) };
 		mem_cgroup_swapout(page, swap);
-		__delete_from_swap_cache(page);
+		__delete_from_swap_cache(page, swap);
 		xa_unlock_irqrestore(&mapping->i_pages, flags);
 		put_swap_page(page, swap);
 	} else {
@@ -948,7 +971,7 @@
 		 */
 		if (reclaimed && page_is_file_cache(page) &&
 		    !mapping_exiting(mapping) && !dax_mapping(mapping))
-			shadow = workingset_eviction(mapping, page);
+			shadow = workingset_eviction(page);
 		__delete_from_page_cache(page, shadow);
 		xa_unlock_irqrestore(&mapping->i_pages, flags);
 
@@ -1098,28 +1121,23 @@
 				      struct scan_control *sc,
 				      enum ttu_flags ttu_flags,
 				      struct reclaim_stat *stat,
-				      bool force_reclaim)
+				      bool ignore_references)
 {
 	LIST_HEAD(ret_pages);
 	LIST_HEAD(free_pages);
-	int pgactivate = 0;
-	unsigned nr_unqueued_dirty = 0;
-	unsigned nr_dirty = 0;
-	unsigned nr_congested = 0;
 	unsigned nr_reclaimed = 0;
-	unsigned nr_writeback = 0;
-	unsigned nr_immediate = 0;
-	unsigned nr_ref_keep = 0;
-	unsigned nr_unmap_fail = 0;
+	unsigned pgactivate = 0;
 
+	memset(stat, 0, sizeof(*stat));
 	cond_resched();
 
 	while (!list_empty(page_list)) {
 		struct address_space *mapping;
 		struct page *page;
 		int may_enter_fs;
-		enum page_references references = PAGEREF_RECLAIM_CLEAN;
+		enum page_references references = PAGEREF_RECLAIM;
 		bool dirty, writeback;
+		unsigned int nr_pages;
 
 		cond_resched();
 
@@ -1131,7 +1149,10 @@
 
 		VM_BUG_ON_PAGE(PageActive(page), page);
 
-		sc->nr_scanned++;
+		nr_pages = compound_nr(page);
+
+		/* Account the number of base pages even though THP */
+		sc->nr_scanned += nr_pages;
 
 		if (unlikely(!page_evictable(page)))
 			goto activate_locked;
@@ -1139,11 +1160,6 @@
 		if (!sc->may_unmap && page_mapped(page))
 			goto keep_locked;
 
-		/* Double the slab pressure for mapped and swapcache pages */
-		if ((page_mapped(page) || PageSwapCache(page)) &&
-		    !(PageAnon(page) && !PageSwapBacked(page)))
-			sc->nr_scanned++;
-
 		may_enter_fs = (sc->gfp_mask & __GFP_FS) ||
 			(PageSwapCache(page) && (sc->gfp_mask & __GFP_IO));
 
@@ -1155,10 +1171,10 @@
 		 */
 		page_check_dirty_writeback(page, &dirty, &writeback);
 		if (dirty || writeback)
-			nr_dirty++;
+			stat->nr_dirty++;
 
 		if (dirty && !writeback)
-			nr_unqueued_dirty++;
+			stat->nr_unqueued_dirty++;
 
 		/*
 		 * Treat this page as congested if the underlying BDI is or if
@@ -1170,7 +1186,7 @@
 		if (((dirty || writeback) && mapping &&
 		     inode_write_congested(mapping->host)) ||
 		    (writeback && PageReclaim(page)))
-			nr_congested++;
+			stat->nr_congested++;
 
 		/*
 		 * If a page at the tail of the LRU is under writeback, there
@@ -1219,7 +1235,7 @@
 			if (current_is_kswapd() &&
 			    PageReclaim(page) &&
 			    test_bit(PGDAT_WRITEBACK, &pgdat->flags)) {
-				nr_immediate++;
+				stat->nr_immediate++;
 				goto activate_locked;
 
 			/* Case 2 above */
@@ -1237,7 +1253,7 @@
 				 * and it's also appropriate in global reclaim.
 				 */
 				SetPageReclaim(page);
-				nr_writeback++;
+				stat->nr_writeback++;
 				goto activate_locked;
 
 			/* Case 3 above */
@@ -1250,14 +1266,14 @@
 			}
 		}
 
-		if (!force_reclaim)
+		if (!ignore_references)
 			references = page_check_references(page, sc);
 
 		switch (references) {
 		case PAGEREF_ACTIVATE:
 			goto activate_locked;
 		case PAGEREF_KEEP:
-			nr_ref_keep++;
+			stat->nr_ref_keep += nr_pages;
 			goto keep_locked;
 		case PAGEREF_RECLAIM:
 		case PAGEREF_RECLAIM_CLEAN:
@@ -1289,7 +1305,7 @@
 				}
 				if (!add_to_swap(page)) {
 					if (!PageTransHuge(page))
-						goto activate_locked;
+						goto activate_locked_split;
 					/* Fallback to swap normal pages */
 					if (split_huge_page_to_list(page,
 								    page_list))
@@ -1298,7 +1314,7 @@
 					count_vm_event(THP_SWPOUT_FALLBACK);
 #endif
 					if (!add_to_swap(page))
-						goto activate_locked;
+						goto activate_locked_split;
 				}
 
 				may_enter_fs = 1;
@@ -1313,6 +1329,18 @@
 		}
 
 		/*
+		 * THP may get split above, need minus tail pages and update
+		 * nr_pages to avoid accounting tail pages twice.
+		 *
+		 * The tail pages that are added into swap cache successfully
+		 * reach here.
+		 */
+		if ((nr_pages > 1) && !PageTransHuge(page)) {
+			sc->nr_scanned -= (nr_pages - 1);
+			nr_pages = 1;
+		}
+
+		/*
 		 * The page is mapped into the page tables of one or more
 		 * processes. Try to unmap it here.
 		 */
@@ -1322,7 +1350,7 @@
 			if (unlikely(PageTransHuge(page)))
 				flags |= TTU_SPLIT_HUGE_PMD;
 			if (!try_to_unmap(page, flags)) {
-				nr_unmap_fail++;
+				stat->nr_unmap_fail += nr_pages;
 				goto activate_locked;
 			}
 		}
@@ -1446,28 +1474,34 @@
 			count_memcg_page_event(page, PGLAZYFREED);
 		} else if (!mapping || !__remove_mapping(mapping, page, true))
 			goto keep_locked;
-		/*
-		 * At this point, we have no other references and there is
-		 * no way to pick any more up (removed from LRU, removed
-		 * from pagecache). Can use non-atomic bitops now (and
-		 * we obviously don't have to worry about waking up a process
-		 * waiting on the page lock, because there are no references.
-		 */
-		__ClearPageLocked(page);
+
+		unlock_page(page);
 free_it:
-		nr_reclaimed++;
+		/*
+		 * THP may get swapped out in a whole, need account
+		 * all base pages.
+		 */
+		nr_reclaimed += nr_pages;
 
 		/*
 		 * Is there need to periodically free_page_list? It would
 		 * appear not as the counts should be low
 		 */
-		if (unlikely(PageTransHuge(page))) {
-			mem_cgroup_uncharge(page);
+		if (unlikely(PageTransHuge(page)))
 			(*get_compound_page_dtor(page))(page);
-		} else
+		else
 			list_add(&page->lru, &free_pages);
 		continue;
 
+activate_locked_split:
+		/*
+		 * The tail pages that are failed to add into swap cache
+		 * reach here.  Fixup nr_scanned and nr_pages.
+		 */
+		if (nr_pages > 1) {
+			sc->nr_scanned -= (nr_pages - 1);
+			nr_pages = 1;
+		}
 activate_locked:
 		/* Not a candidate for swapping, so reclaim swap space. */
 		if (PageSwapCache(page) && (mem_cgroup_swap_full(page) ||
@@ -1475,8 +1509,9 @@
 			try_to_free_swap(page);
 		VM_BUG_ON_PAGE(PageActive(page), page);
 		if (!PageMlocked(page)) {
+			int type = page_is_file_cache(page);
 			SetPageActive(page);
-			pgactivate++;
+			stat->nr_activate[type] += nr_pages;
 			count_memcg_page_event(page, PGACTIVATE);
 		}
 keep_locked:
@@ -1486,6 +1521,8 @@
 		VM_BUG_ON_PAGE(PageLRU(page) || PageUnevictable(page), page);
 	}
 
+	pgactivate = stat->nr_activate[0] + stat->nr_activate[1];
+
 	mem_cgroup_uncharge_list(&free_pages);
 	try_to_unmap_flush();
 	free_unref_page_list(&free_pages);
@@ -1493,16 +1530,6 @@
 	list_splice(&ret_pages, page_list);
 	count_vm_events(PGACTIVATE, pgactivate);
 
-	if (stat) {
-		stat->nr_dirty = nr_dirty;
-		stat->nr_congested = nr_congested;
-		stat->nr_unqueued_dirty = nr_unqueued_dirty;
-		stat->nr_writeback = nr_writeback;
-		stat->nr_immediate = nr_immediate;
-		stat->nr_activate = pgactivate;
-		stat->nr_ref_keep = nr_ref_keep;
-		stat->nr_unmap_fail = nr_unmap_fail;
-	}
 	return nr_reclaimed;
 }
 
@@ -1514,20 +1541,21 @@
 		.priority = DEF_PRIORITY,
 		.may_unmap = 1,
 	};
+	struct reclaim_stat dummy_stat;
 	unsigned long ret;
 	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) &&
-		    !__PageMovable(page)) {
+		    !__PageMovable(page) && !PageUnevictable(page)) {
 			ClearPageActive(page);
 			list_move(&page->lru, &clean_pages);
 		}
 	}
 
 	ret = shrink_page_list(&clean_pages, zone->zone_pgdat, &sc,
-			TTU_IGNORE_ACCESS, NULL, true);
+			TTU_IGNORE_ACCESS, &dummy_stat, true);
 	list_splice(&clean_pages, page_list);
 	mod_node_page_state(zone->zone_pgdat, NR_ISOLATED_FILE, -ret);
 	return ret;
@@ -1632,8 +1660,8 @@
 
 }
 
-/*
- * zone_lru_lock is heavily contended.  Some of the functions that
+/**
+ * pgdat->lru_lock is heavily contended.  Some of the functions that
  * shrink the lists perform better by taking out a batch of pages
  * and working on them outside the LRU lock.
  *
@@ -1655,7 +1683,7 @@
 static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 		struct lruvec *lruvec, struct list_head *dst,
 		unsigned long *nr_scanned, struct scan_control *sc,
-		isolate_mode_t mode, enum lru_list lru)
+		enum lru_list lru)
 {
 	struct list_head *src = &lruvec->lists[lru];
 	unsigned long nr_taken = 0;
@@ -1664,11 +1692,11 @@
 	unsigned long skipped = 0;
 	unsigned long scan, total_scan, nr_pages;
 	LIST_HEAD(pages_skipped);
+	isolate_mode_t mode = (sc->may_unmap ? 0 : ISOLATE_UNMAPPED);
 
+	total_scan = 0;
 	scan = 0;
-	for (total_scan = 0;
-	     scan < nr_to_scan && nr_taken < nr_to_scan && !list_empty(src);
-	     total_scan++) {
+	while (scan < nr_to_scan && !list_empty(src)) {
 		struct page *page;
 
 		page = lru_to_page(src);
@@ -1676,9 +1704,12 @@
 
 		VM_BUG_ON_PAGE(!PageLRU(page), page);
 
+		nr_pages = compound_nr(page);
+		total_scan += nr_pages;
+
 		if (page_zonenum(page) > sc->reclaim_idx) {
 			list_move(&page->lru, &pages_skipped);
-			nr_skipped[page_zonenum(page)]++;
+			nr_skipped[page_zonenum(page)] += nr_pages;
 			continue;
 		}
 
@@ -1687,11 +1718,14 @@
 		 * return with no isolated pages if the LRU mostly contains
 		 * ineligible pages.  This causes the VM to not reclaim any
 		 * pages, triggering a premature OOM.
+		 *
+		 * Account all tail pages of THP.  This would not cause
+		 * premature OOM since __isolate_lru_page() returns -EBUSY
+		 * only when the page is being freed somewhere else.
 		 */
-		scan++;
+		scan += nr_pages;
 		switch (__isolate_lru_page(page, mode)) {
 		case 0:
-			nr_pages = hpage_nr_pages(page);
 			nr_taken += nr_pages;
 			nr_zone_taken[page_zonenum(page)] += nr_pages;
 			list_move(&page->lru, dst);
@@ -1767,11 +1801,11 @@
 	WARN_RATELIMIT(PageTail(page), "trying to isolate tail page");
 
 	if (PageLRU(page)) {
-		struct zone *zone = page_zone(page);
+		pg_data_t *pgdat = page_pgdat(page);
 		struct lruvec *lruvec;
 
-		spin_lock_irq(zone_lru_lock(zone));
-		lruvec = mem_cgroup_page_lruvec(page, zone->zone_pgdat);
+		spin_lock_irq(&pgdat->lru_lock);
+		lruvec = mem_cgroup_page_lruvec(page, pgdat);
 		if (PageLRU(page)) {
 			int lru = page_lru(page);
 			get_page(page);
@@ -1779,7 +1813,7 @@
 			del_page_from_lru_list(page, lruvec, lru);
 			ret = 0;
 		}
-		spin_unlock_irq(zone_lru_lock(zone));
+		spin_unlock_irq(&pgdat->lru_lock);
 	}
 	return ret;
 }
@@ -1821,40 +1855,54 @@
 	return isolated > inactive;
 }
 
-static noinline_for_stack void
-putback_inactive_pages(struct lruvec *lruvec, struct list_head *page_list)
+/*
+ * This moves pages from @list to corresponding LRU list.
+ *
+ * We move them the other way if the page is referenced by one or more
+ * processes, from rmap.
+ *
+ * If the pages are mostly unmapped, the processing is fast and it is
+ * appropriate to hold zone_lru_lock across the whole operation.  But if
+ * the pages are mapped, the processing is slow (page_referenced()) so we
+ * should drop zone_lru_lock around each page.  It's impossible to balance
+ * this, so instead we remove the pages from the LRU while processing them.
+ * It is safe to rely on PG_active against the non-LRU pages in here because
+ * nobody will play with that bit on a non-LRU page.
+ *
+ * The downside is that we have to touch page->_refcount against each page.
+ * But we had to alter page->flags anyway.
+ *
+ * Returns the number of pages moved to the given lruvec.
+ */
+
+static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
+						     struct list_head *list)
 {
-	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
+	int nr_pages, nr_moved = 0;
 	LIST_HEAD(pages_to_free);
+	struct page *page;
+	enum lru_list lru;
 
-	/*
-	 * Put back any unfreeable pages.
-	 */
-	while (!list_empty(page_list)) {
-		struct page *page = lru_to_page(page_list);
-		int lru;
-
+	while (!list_empty(list)) {
+		page = lru_to_page(list);
 		VM_BUG_ON_PAGE(PageLRU(page), page);
-		list_del(&page->lru);
 		if (unlikely(!page_evictable(page))) {
+			list_del(&page->lru);
 			spin_unlock_irq(&pgdat->lru_lock);
 			putback_lru_page(page);
 			spin_lock_irq(&pgdat->lru_lock);
 			continue;
 		}
-
 		lruvec = mem_cgroup_page_lruvec(page, pgdat);
 
 		SetPageLRU(page);
 		lru = page_lru(page);
-		add_page_to_lru_list(page, lruvec, lru);
 
-		if (is_active_lru(lru)) {
-			int file = is_file_lru(lru);
-			int numpages = hpage_nr_pages(page);
-			reclaim_stat->recent_rotated[file] += numpages;
-		}
+		nr_pages = hpage_nr_pages(page);
+		update_lru_size(lruvec, lru, page_zonenum(page), nr_pages);
+		list_move(&page->lru, &lruvec->lists[lru]);
+
 		if (put_page_testzero(page)) {
 			__ClearPageLRU(page);
 			__ClearPageActive(page);
@@ -1862,18 +1910,21 @@
 
 			if (unlikely(PageCompound(page))) {
 				spin_unlock_irq(&pgdat->lru_lock);
-				mem_cgroup_uncharge(page);
 				(*get_compound_page_dtor(page))(page);
 				spin_lock_irq(&pgdat->lru_lock);
 			} else
 				list_add(&page->lru, &pages_to_free);
+		} else {
+			nr_moved += nr_pages;
 		}
 	}
 
 	/*
 	 * To save our caller's stack, now use input list for pages to free.
 	 */
-	list_splice(&pages_to_free, page_list);
+	list_splice(&pages_to_free, list);
+
+	return nr_moved;
 }
 
 /*
@@ -1901,9 +1952,9 @@
 	unsigned long nr_scanned;
 	unsigned long nr_reclaimed = 0;
 	unsigned long nr_taken;
-	struct reclaim_stat stat = {};
-	isolate_mode_t isolate_mode = 0;
+	struct reclaim_stat stat;
 	int file = is_file_lru(lru);
+	enum vm_event_item item;
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
 	bool stalled = false;
@@ -1923,28 +1974,18 @@
 
 	lru_add_drain();
 
-	if (!sc->may_unmap)
-		isolate_mode |= ISOLATE_UNMAPPED;
-
 	spin_lock_irq(&pgdat->lru_lock);
 
 	nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &page_list,
-				     &nr_scanned, sc, isolate_mode, lru);
+				     &nr_scanned, sc, lru);
 
 	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, nr_taken);
 	reclaim_stat->recent_scanned[file] += nr_taken;
 
-	if (current_is_kswapd()) {
-		if (global_reclaim(sc))
-			__count_vm_events(PGSCAN_KSWAPD, nr_scanned);
-		count_memcg_events(lruvec_memcg(lruvec), PGSCAN_KSWAPD,
-				   nr_scanned);
-	} else {
-		if (global_reclaim(sc))
-			__count_vm_events(PGSCAN_DIRECT, nr_scanned);
-		count_memcg_events(lruvec_memcg(lruvec), PGSCAN_DIRECT,
-				   nr_scanned);
-	}
+	item = current_is_kswapd() ? PGSCAN_KSWAPD : PGSCAN_DIRECT;
+	if (global_reclaim(sc))
+		__count_vm_events(item, nr_scanned);
+	__count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned);
 	spin_unlock_irq(&pgdat->lru_lock);
 
 	if (nr_taken == 0)
@@ -1955,19 +1996,14 @@
 
 	spin_lock_irq(&pgdat->lru_lock);
 
-	if (current_is_kswapd()) {
-		if (global_reclaim(sc))
-			__count_vm_events(PGSTEAL_KSWAPD, nr_reclaimed);
-		count_memcg_events(lruvec_memcg(lruvec), PGSTEAL_KSWAPD,
-				   nr_reclaimed);
-	} else {
-		if (global_reclaim(sc))
-			__count_vm_events(PGSTEAL_DIRECT, nr_reclaimed);
-		count_memcg_events(lruvec_memcg(lruvec), PGSTEAL_DIRECT,
-				   nr_reclaimed);
-	}
+	item = current_is_kswapd() ? PGSTEAL_KSWAPD : PGSTEAL_DIRECT;
+	if (global_reclaim(sc))
+		__count_vm_events(item, nr_reclaimed);
+	__count_memcg_events(lruvec_memcg(lruvec), item, nr_reclaimed);
+	reclaim_stat->recent_rotated[0] += stat.nr_activate[0];
+	reclaim_stat->recent_rotated[1] += stat.nr_activate[1];
 
-	putback_inactive_pages(lruvec, &page_list);
+	move_pages_to_lru(lruvec, &page_list);
 
 	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
 
@@ -2004,73 +2040,6 @@
 	return nr_reclaimed;
 }
 
-/*
- * This moves pages from the active list to the inactive list.
- *
- * We move them the other way if the page is referenced by one or more
- * processes, from rmap.
- *
- * If the pages are mostly unmapped, the processing is fast and it is
- * appropriate to hold zone_lru_lock across the whole operation.  But if
- * the pages are mapped, the processing is slow (page_referenced()) so we
- * should drop zone_lru_lock around each page.  It's impossible to balance
- * this, so instead we remove the pages from the LRU while processing them.
- * It is safe to rely on PG_active against the non-LRU pages in here because
- * nobody will play with that bit on a non-LRU page.
- *
- * The downside is that we have to touch page->_refcount against each page.
- * But we had to alter page->flags anyway.
- *
- * Returns the number of pages moved to the given lru.
- */
-
-static unsigned move_active_pages_to_lru(struct lruvec *lruvec,
-				     struct list_head *list,
-				     struct list_head *pages_to_free,
-				     enum lru_list lru)
-{
-	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
-	struct page *page;
-	int nr_pages;
-	int nr_moved = 0;
-
-	while (!list_empty(list)) {
-		page = lru_to_page(list);
-		lruvec = mem_cgroup_page_lruvec(page, pgdat);
-
-		VM_BUG_ON_PAGE(PageLRU(page), page);
-		SetPageLRU(page);
-
-		nr_pages = hpage_nr_pages(page);
-		update_lru_size(lruvec, lru, page_zonenum(page), nr_pages);
-		list_move(&page->lru, &lruvec->lists[lru]);
-
-		if (put_page_testzero(page)) {
-			__ClearPageLRU(page);
-			__ClearPageActive(page);
-			del_page_from_lru_list(page, lruvec, lru);
-
-			if (unlikely(PageCompound(page))) {
-				spin_unlock_irq(&pgdat->lru_lock);
-				mem_cgroup_uncharge(page);
-				(*get_compound_page_dtor(page))(page);
-				spin_lock_irq(&pgdat->lru_lock);
-			} else
-				list_add(&page->lru, pages_to_free);
-		} else {
-			nr_moved += nr_pages;
-		}
-	}
-
-	if (!is_active_lru(lru)) {
-		__count_vm_events(PGDEACTIVATE, nr_moved);
-		count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE,
-				   nr_moved);
-	}
-
-	return nr_moved;
-}
-
 static void shrink_active_list(unsigned long nr_to_scan,
 			       struct lruvec *lruvec,
 			       struct scan_control *sc,
@@ -2086,25 +2055,21 @@
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
 	unsigned nr_deactivate, nr_activate;
 	unsigned nr_rotated = 0;
-	isolate_mode_t isolate_mode = 0;
 	int file = is_file_lru(lru);
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 
 	lru_add_drain();
 
-	if (!sc->may_unmap)
-		isolate_mode |= ISOLATE_UNMAPPED;
-
 	spin_lock_irq(&pgdat->lru_lock);
 
 	nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &l_hold,
-				     &nr_scanned, sc, isolate_mode, lru);
+				     &nr_scanned, sc, lru);
 
 	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, nr_taken);
 	reclaim_stat->recent_scanned[file] += nr_taken;
 
 	__count_vm_events(PGREFILL, nr_scanned);
-	count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned);
+	__count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned);
 
 	spin_unlock_irq(&pgdat->lru_lock);
 
@@ -2145,6 +2110,7 @@
 		}
 
 		ClearPageActive(page);	/* we are de-activating */
+		SetPageWorkingset(page);
 		list_add(&page->lru, &l_inactive);
 	}
 
@@ -2160,17 +2126,79 @@
 	 */
 	reclaim_stat->recent_rotated[file] += nr_rotated;
 
-	nr_activate = move_active_pages_to_lru(lruvec, &l_active, &l_hold, lru);
-	nr_deactivate = move_active_pages_to_lru(lruvec, &l_inactive, &l_hold, lru - LRU_ACTIVE);
+	nr_activate = move_pages_to_lru(lruvec, &l_active);
+	nr_deactivate = move_pages_to_lru(lruvec, &l_inactive);
+	/* Keep all free pages in l_active list */
+	list_splice(&l_inactive, &l_active);
+
+	__count_vm_events(PGDEACTIVATE, nr_deactivate);
+	__count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_deactivate);
+
 	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
 	spin_unlock_irq(&pgdat->lru_lock);
 
-	mem_cgroup_uncharge_list(&l_hold);
-	free_unref_page_list(&l_hold);
+	mem_cgroup_uncharge_list(&l_active);
+	free_unref_page_list(&l_active);
 	trace_mm_vmscan_lru_shrink_active(pgdat->node_id, nr_taken, nr_activate,
 			nr_deactivate, nr_rotated, sc->priority, file);
 }
 
+unsigned long reclaim_pages(struct list_head *page_list)
+{
+	int nid = -1;
+	unsigned long nr_reclaimed = 0;
+	LIST_HEAD(node_page_list);
+	struct reclaim_stat dummy_stat;
+	struct page *page;
+	struct scan_control sc = {
+		.gfp_mask = GFP_KERNEL,
+		.priority = DEF_PRIORITY,
+		.may_writepage = 1,
+		.may_unmap = 1,
+		.may_swap = 1,
+	};
+
+	while (!list_empty(page_list)) {
+		page = lru_to_page(page_list);
+		if (nid == -1) {
+			nid = page_to_nid(page);
+			INIT_LIST_HEAD(&node_page_list);
+		}
+
+		if (nid == page_to_nid(page)) {
+			ClearPageActive(page);
+			list_move(&page->lru, &node_page_list);
+			continue;
+		}
+
+		nr_reclaimed += shrink_page_list(&node_page_list,
+						NODE_DATA(nid),
+						&sc, 0,
+						&dummy_stat, false);
+		while (!list_empty(&node_page_list)) {
+			page = lru_to_page(&node_page_list);
+			list_del(&page->lru);
+			putback_lru_page(page);
+		}
+
+		nid = -1;
+	}
+
+	if (!list_empty(&node_page_list)) {
+		nr_reclaimed += shrink_page_list(&node_page_list,
+						NODE_DATA(nid),
+						&sc, 0,
+						&dummy_stat, false);
+		while (!list_empty(&node_page_list)) {
+			page = lru_to_page(&node_page_list);
+			list_del(&page->lru);
+			putback_lru_page(page);
+		}
+	}
+
+	return nr_reclaimed;
+}
+
 /*
  * The inactive anon list should be small enough that the VM never has
  * to do too much work.
@@ -2200,8 +2228,7 @@
  *   10TB     320        32GB
  */
 static bool inactive_list_is_low(struct lruvec *lruvec, bool file,
-				 struct mem_cgroup *memcg,
-				 struct scan_control *sc, bool actual_reclaim)
+				 struct scan_control *sc, bool trace)
 {
 	enum lru_list active_lru = file * LRU_FILE + LRU_ACTIVE;
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
@@ -2221,17 +2248,13 @@
 	inactive = lruvec_lru_size(lruvec, inactive_lru, sc->reclaim_idx);
 	active = lruvec_lru_size(lruvec, active_lru, sc->reclaim_idx);
 
-	if (memcg)
-		refaults = memcg_page_state(memcg, WORKINGSET_ACTIVATE);
-	else
-		refaults = node_page_state(pgdat, WORKINGSET_ACTIVATE);
-
 	/*
 	 * When refaults are being observed, it means a new workingset
 	 * is being established. Disable active list protection to get
 	 * rid of the stale workingset quickly.
 	 */
-	if (file && actual_reclaim && lruvec->refaults != refaults) {
+	refaults = lruvec_page_state_local(lruvec, WORKINGSET_ACTIVATE);
+	if (file && lruvec->refaults != refaults) {
 		inactive_ratio = 0;
 	} else {
 		gb = (inactive + active) >> (30 - PAGE_SHIFT);
@@ -2241,7 +2264,7 @@
 			inactive_ratio = 1;
 	}
 
-	if (actual_reclaim)
+	if (trace)
 		trace_mm_vmscan_inactive_list_is_low(pgdat->node_id, sc->reclaim_idx,
 			lruvec_lru_size(lruvec, inactive_lru, MAX_NR_ZONES), inactive,
 			lruvec_lru_size(lruvec, active_lru, MAX_NR_ZONES), active,
@@ -2251,12 +2274,10 @@
 }
 
 static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan,
-				 struct lruvec *lruvec, struct mem_cgroup *memcg,
-				 struct scan_control *sc)
+				 struct lruvec *lruvec, struct scan_control *sc)
 {
 	if (is_active_lru(lru)) {
-		if (inactive_list_is_low(lruvec, is_file_lru(lru),
-					 memcg, sc, true))
+		if (inactive_list_is_low(lruvec, is_file_lru(lru), sc, true))
 			shrink_active_list(nr_to_scan, lruvec, sc, lru);
 		return 0;
 	}
@@ -2356,7 +2377,7 @@
 			 * anonymous pages on the LRU in eligible zones.
 			 * Otherwise, the small LRU gets thrashed.
 			 */
-			if (!inactive_list_is_low(lruvec, false, memcg, sc, false) &&
+			if (!inactive_list_is_low(lruvec, false, sc, false) &&
 			    lruvec_lru_size(lruvec, LRU_INACTIVE_ANON, sc->reclaim_idx)
 					>> sc->priority) {
 				scan_balance = SCAN_ANON;
@@ -2374,7 +2395,7 @@
 	 * lruvec even if it has plenty of old anonymous pages unless the
 	 * system is under heavy pressure.
 	 */
-	if (!inactive_list_is_low(lruvec, true, memcg, sc, false) &&
+	if (!inactive_list_is_low(lruvec, true, sc, false) &&
 	    lruvec_lru_size(lruvec, LRU_INACTIVE_FILE, sc->reclaim_idx) >> sc->priority) {
 		scan_balance = SCAN_FILE;
 		goto out;
@@ -2436,17 +2457,70 @@
 	*lru_pages = 0;
 	for_each_evictable_lru(lru) {
 		int file = is_file_lru(lru);
-		unsigned long size;
+		unsigned long lruvec_size;
 		unsigned long scan;
+		unsigned long protection;
 
-		size = lruvec_lru_size(lruvec, lru, sc->reclaim_idx);
-		scan = size >> sc->priority;
+		lruvec_size = lruvec_lru_size(lruvec, lru, sc->reclaim_idx);
+		protection = mem_cgroup_protection(memcg,
+						   sc->memcg_low_reclaim);
+
+		if (protection) {
+			/*
+			 * Scale a cgroup's reclaim pressure by proportioning
+			 * its current usage to its memory.low or memory.min
+			 * setting.
+			 *
+			 * This is important, as otherwise scanning aggression
+			 * becomes extremely binary -- from nothing as we
+			 * approach the memory protection threshold, to totally
+			 * nominal as we exceed it.  This results in requiring
+			 * setting extremely liberal protection thresholds. It
+			 * also means we simply get no protection at all if we
+			 * set it too low, which is not ideal.
+			 *
+			 * If there is any protection in place, we reduce scan
+			 * pressure by how much of the total memory used is
+			 * within protection thresholds.
+			 *
+			 * There is one special case: in the first reclaim pass,
+			 * we skip over all groups that are within their low
+			 * protection. If that fails to reclaim enough pages to
+			 * satisfy the reclaim goal, we come back and override
+			 * the best-effort low protection. However, we still
+			 * ideally want to honor how well-behaved groups are in
+			 * that case instead of simply punishing them all
+			 * equally. As such, we reclaim them based on how much
+			 * memory they are using, reducing the scan pressure
+			 * again by how much of the total memory used is under
+			 * hard protection.
+			 */
+			unsigned long cgroup_size = mem_cgroup_size(memcg);
+
+			/* Avoid TOCTOU with earlier protection check */
+			cgroup_size = max(cgroup_size, protection);
+
+			scan = lruvec_size - lruvec_size * protection /
+				cgroup_size;
+
+			/*
+			 * Minimally target SWAP_CLUSTER_MAX pages to keep
+			 * reclaim moving forwards, avoiding decremeting
+			 * sc->priority further than desirable.
+			 */
+			scan = max(scan, SWAP_CLUSTER_MAX);
+		} else {
+			scan = lruvec_size;
+		}
+
+		scan >>= sc->priority;
+
 		/*
 		 * If the cgroup's already been deleted, make sure to
 		 * scrape out the remaining cache.
 		 */
 		if (!scan && !mem_cgroup_online(memcg))
-			scan = min(size, SWAP_CLUSTER_MAX);
+			scan = min(lruvec_size, SWAP_CLUSTER_MAX);
 
 		switch (scan_balance) {
 		case SCAN_EQUAL:
@@ -2466,7 +2540,7 @@
 		case SCAN_ANON:
 			/* Scan one type exclusively */
 			if ((scan_balance == SCAN_FILE) != file) {
-				size = 0;
+				lruvec_size = 0;
 				scan = 0;
 			}
 			break;
@@ -2475,7 +2549,7 @@
 			BUG();
 		}
 
-		*lru_pages += size;
+		*lru_pages += lruvec_size;
 		nr[lru] = scan;
 	}
 }
@@ -2527,7 +2601,7 @@
 				nr[lru] -= nr_to_scan;
 
 				nr_reclaimed += shrink_list(lru, nr_to_scan,
-							    lruvec, memcg, sc);
+							    lruvec, sc);
 			}
 		}
 
@@ -2594,7 +2668,7 @@
 	 * Even if we did not try to evict anon pages at all, we want to
 	 * rebalance the anon lru active/inactive ratio.
 	 */
-	if (inactive_list_is_low(lruvec, false, memcg, sc, true))
+	if (inactive_list_is_low(lruvec, false, sc, true))
 		shrink_active_list(SWAP_CLUSTER_MAX, lruvec,
 				   sc, LRU_ACTIVE_ANON);
 }
@@ -2619,7 +2693,6 @@
  */
 static inline bool should_continue_reclaim(struct pglist_data *pgdat,
 					unsigned long nr_reclaimed,
-					unsigned long nr_scanned,
 					struct scan_control *sc)
 {
 	unsigned long pages_for_compaction;
@@ -2630,40 +2703,18 @@
 	if (!in_reclaim_compaction(sc))
 		return false;
 
-	/* Consider stopping depending on scan and reclaim activity */
-	if (sc->gfp_mask & __GFP_RETRY_MAYFAIL) {
-		/*
-		 * For __GFP_RETRY_MAYFAIL allocations, stop reclaiming if the
-		 * full LRU list has been scanned and we are still failing
-		 * to reclaim pages. This full LRU scan is potentially
-		 * expensive but a __GFP_RETRY_MAYFAIL caller really wants to succeed
-		 */
-		if (!nr_reclaimed && !nr_scanned)
-			return false;
-	} else {
-		/*
-		 * For non-__GFP_RETRY_MAYFAIL allocations which can presumably
-		 * fail without consequence, stop if we failed to reclaim
-		 * any pages from the last SWAP_CLUSTER_MAX number of
-		 * pages that were scanned. This will return to the
-		 * caller faster at the risk reclaim/compaction and
-		 * the resulting allocation attempt fails
-		 */
-		if (!nr_reclaimed)
-			return false;
-	}
-
 	/*
-	 * If we have not reclaimed enough pages for compaction and the
-	 * inactive lists are large enough, continue reclaiming
+	 * Stop if we failed to reclaim any pages from the last SWAP_CLUSTER_MAX
+	 * number of pages that were scanned. This will return to the caller
+	 * with the risk reclaim/compaction and the resulting allocation attempt
+	 * fails. In the past we have tried harder for __GFP_RETRY_MAYFAIL
+	 * allocations through requiring that the full LRU list has been scanned
+	 * first, by assuming that zero delta of sc->nr_scanned means full LRU
+	 * scan, but that approximation was wrong, and there were corner cases
+	 * where always a non-zero amount of pages were scanned.
 	 */
-	pages_for_compaction = compact_gap(sc->order);
-	inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE);
-	if (get_nr_swap_pages() > 0)
-		inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
-	if (sc->nr_reclaimed < pages_for_compaction &&
-			inactive_lru_pages > pages_for_compaction)
-		return true;
+	if (!nr_reclaimed)
+		return false;
 
 	/* If compaction would go ahead or the allocation would succeed, stop */
 	for (z = 0; z <= sc->reclaim_idx; z++) {
@@ -2680,7 +2731,17 @@
 			;
 		}
 	}
-	return true;
+
+	/*
+	 * If we have not reclaimed enough pages for compaction and the
+	 * inactive lists are large enough, continue reclaiming
+	 */
+	pages_for_compaction = compact_gap(sc->order);
+	inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE);
+	if (get_nr_swap_pages() > 0)
+		inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
+
+	return inactive_lru_pages > pages_for_compaction;
 }
 
 static bool pgdat_memcg_congested(pg_data_t *pgdat, struct mem_cgroup *memcg)
@@ -2697,10 +2758,6 @@
 
 	do {
 		struct mem_cgroup *root = sc->target_mem_cgroup;
-		struct mem_cgroup_reclaim_cookie reclaim = {
-			.pgdat = pgdat,
-			.priority = sc->priority,
-		};
 		unsigned long node_lru_pages = 0;
 		struct mem_cgroup *memcg;
 
@@ -2709,7 +2766,7 @@
 		nr_reclaimed = sc->nr_reclaimed;
 		nr_scanned = sc->nr_scanned;
 
-		memcg = mem_cgroup_iter(root, NULL, &reclaim);
+		memcg = mem_cgroup_iter(root, NULL, NULL);
 		do {
 			unsigned long lru_pages;
 			unsigned long reclaimed;
@@ -2736,6 +2793,13 @@
 				memcg_memory_event(memcg, MEMCG_LOW);
 				break;
 			case MEMCG_PROT_NONE:
+				/*
+				 * All protection thresholds breached. We may
+				 * still choose to vary the scan pressure
+				 * applied based on by how much the cgroup in
+				 * question has exceeded its protection
+				 * thresholds (see get_scan_count).
+				 */
 				break;
 			}
 
@@ -2744,30 +2808,15 @@
 			shrink_node_memcg(pgdat, memcg, sc, &lru_pages);
 			node_lru_pages += lru_pages;
 
-			shrink_slab(sc->gfp_mask, pgdat->node_id,
-				    memcg, sc->priority);
+			shrink_slab(sc->gfp_mask, pgdat->node_id, memcg,
+					sc->priority);
 
 			/* Record the group's reclaim efficiency */
 			vmpressure(sc->gfp_mask, memcg, false,
 				   sc->nr_scanned - scanned,
 				   sc->nr_reclaimed - reclaimed);
 
-			/*
-			 * Direct reclaim and kswapd have to scan all memory
-			 * cgroups to fulfill the overall scan target for the
-			 * node.
-			 *
-			 * Limit reclaim, on the other hand, only cares about
-			 * nr_to_reclaim pages to be reclaimed and it will
-			 * retry with decreasing priority if one round over the
-			 * whole hierarchy is not sufficient.
-			 */
-			if (!global_reclaim(sc) &&
-					sc->nr_reclaimed >= sc->nr_to_reclaim) {
-				mem_cgroup_iter_break(root, memcg);
-				break;
-			}
-		} while ((memcg = mem_cgroup_iter(root, memcg, &reclaim)));
+		} while ((memcg = mem_cgroup_iter(root, memcg, NULL)));
 
 		if (reclaim_state) {
 			sc->nr_reclaimed += reclaim_state->reclaimed_slab;
@@ -2844,7 +2893,7 @@
 			wait_iff_congested(BLK_RW_ASYNC, HZ/10);
 
 	} while (should_continue_reclaim(pgdat, sc->nr_reclaimed - nr_reclaimed,
-					 sc->nr_scanned - nr_scanned, sc));
+					 sc));
 
 	/*
 	 * Kswapd gives up on balancing particular nodes after too
@@ -2992,12 +3041,8 @@
 		unsigned long refaults;
 		struct lruvec *lruvec;
 
-		if (memcg)
-			refaults = memcg_page_state(memcg, WORKINGSET_ACTIVATE);
-		else
-			refaults = node_page_state(pgdat, WORKINGSET_ACTIVATE);
-
 		lruvec = mem_cgroup_lruvec(pgdat, memcg);
+		refaults = lruvec_page_state_local(lruvec, WORKINGSET_ACTIVATE);
 		lruvec->refaults = refaults;
 	} while ((memcg = mem_cgroup_iter(root_memcg, memcg, NULL)));
 }
@@ -3245,20 +3290,20 @@
 	if (throttle_direct_reclaim(sc.gfp_mask, zonelist, nodemask))
 		return 1;
 
-	trace_mm_vmscan_direct_reclaim_begin(order,
-				sc.may_writepage,
-				sc.gfp_mask,
-				sc.reclaim_idx);
+	set_task_reclaim_state(current, &sc.reclaim_state);
+	trace_mm_vmscan_direct_reclaim_begin(order, sc.gfp_mask);
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
 	trace_mm_vmscan_direct_reclaim_end(nr_reclaimed);
+	set_task_reclaim_state(current, NULL);
 
 	return nr_reclaimed;
 }
 
 #ifdef CONFIG_MEMCG
 
+/* Only used by soft limit reclaim. Do not reuse for anything else. */
 unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
 						gfp_t gfp_mask, bool noswap,
 						pg_data_t *pgdat,
@@ -3274,13 +3319,13 @@
 	};
 	unsigned long lru_pages;
 
+	WARN_ON_ONCE(!current->reclaim_state);
+
 	sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
 			(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
 
 	trace_mm_vmscan_memcg_softlimit_reclaim_begin(sc.order,
-						      sc.may_writepage,
-						      sc.gfp_mask,
-						      sc.reclaim_idx);
+						      sc.gfp_mask);
 
 	/*
 	 * NOTE: Although we can get the priority field, using it
@@ -3294,6 +3339,7 @@
 	trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
 
 	*nr_scanned = sc.nr_scanned;
+
 	return sc.nr_reclaimed;
 }
 
@@ -3304,6 +3350,7 @@
 {
 	struct zonelist *zonelist;
 	unsigned long nr_reclaimed;
+	unsigned long pflags;
 	int nid;
 	unsigned int noreclaim_flag;
 	struct scan_control sc = {
@@ -3318,6 +3365,7 @@
 		.may_swap = may_swap,
 	};
 
+	set_task_reclaim_state(current, &sc.reclaim_state);
 	/*
 	 * Unlike direct reclaim via alloc_pages(), memcg's reclaim doesn't
 	 * take care of from where we get pages. So the node where we start the
@@ -3327,16 +3375,18 @@
 
 	zonelist = &NODE_DATA(nid)->node_zonelists[ZONELIST_FALLBACK];
 
-	trace_mm_vmscan_memcg_reclaim_begin(0,
-					    sc.may_writepage,
-					    sc.gfp_mask,
-					    sc.reclaim_idx);
+	trace_mm_vmscan_memcg_reclaim_begin(0, sc.gfp_mask);
 
+	psi_memstall_enter(&pflags);
 	noreclaim_flag = memalloc_noreclaim_save();
+
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
+
 	memalloc_noreclaim_restore(noreclaim_flag);
+	psi_memstall_leave(&pflags);
 
 	trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);
+	set_task_reclaim_state(current, NULL);
 
 	return nr_reclaimed;
 }
@@ -3354,7 +3404,7 @@
 	do {
 		struct lruvec *lruvec = mem_cgroup_lruvec(pgdat, memcg);
 
-		if (inactive_list_is_low(lruvec, false, memcg, sc, true))
+		if (inactive_list_is_low(lruvec, false, sc, true))
 			shrink_active_list(SWAP_CLUSTER_MAX, lruvec,
 					   sc, LRU_ACTIVE_ANON);
 
@@ -3362,6 +3412,30 @@
 	} while (memcg);
 }
 
+static bool pgdat_watermark_boosted(pg_data_t *pgdat, int classzone_idx)
+{
+	int i;
+	struct zone *zone;
+
+	/*
+	 * Check for watermark boosts top-down as the higher zones
+	 * are more likely to be boosted. Both watermarks and boosts
+	 * should not be checked at the time time as reclaim would
+	 * start prematurely when there is no boosting and a lower
+	 * zone is balanced.
+	 */
+	for (i = classzone_idx; i >= 0; i--) {
+		zone = pgdat->node_zones + i;
+		if (!managed_zone(zone))
+			continue;
+
+		if (zone->watermark_boost)
+			return true;
+	}
+
+	return false;
+}
+
 /*
  * Returns true if there is an eligible zone balanced for the request order
  * and classzone_idx
@@ -3372,6 +3446,10 @@
 	unsigned long mark = -1;
 	struct zone *zone;
 
+	/*
+	 * Check watermarks bottom-up as lower zones are more likely to
+	 * meet watermarks.
+	 */
 	for (i = 0; i <= classzone_idx; i++) {
 		zone = pgdat->node_zones + i;
 
@@ -3490,7 +3568,7 @@
  *
  * kswapd scans the zones in the highmem->normal->dma direction.  It skips
  * zones which have free_pages > high_wmark_pages(zone), but once a zone is
- * found to have free_pages <= high_wmark_pages(zone), any page is that zone
+ * found to have free_pages <= high_wmark_pages(zone), any page in that zone
  * or lower is eligible for reclaim until at least one usable zone is
  * balanced.
  */
@@ -3499,23 +3577,45 @@
 	int i;
 	unsigned long nr_soft_reclaimed;
 	unsigned long nr_soft_scanned;
+	unsigned long pflags;
+	unsigned long nr_boost_reclaim;
+	unsigned long zone_boosts[MAX_NR_ZONES] = { 0, };
+	bool boosted;
 	struct zone *zone;
 	struct scan_control sc = {
 		.gfp_mask = GFP_KERNEL,
 		.order = order,
-		.priority = DEF_PRIORITY,
-		.may_writepage = !laptop_mode,
 		.may_unmap = 1,
-		.may_swap = 1,
 	};
 
+	set_task_reclaim_state(current, &sc.reclaim_state);
+	psi_memstall_enter(&pflags);
 	__fs_reclaim_acquire();
 
 	count_vm_event(PAGEOUTRUN);
 
+	/*
+	 * Account for the reclaim boost. Note that the zone boost is left in
+	 * place so that parallel allocations that are near the watermark will
+	 * stall or direct reclaim until kswapd is finished.
+	 */
+	nr_boost_reclaim = 0;
+	for (i = 0; i <= classzone_idx; i++) {
+		zone = pgdat->node_zones + i;
+		if (!managed_zone(zone))
+			continue;
+
+		nr_boost_reclaim += zone->watermark_boost;
+		zone_boosts[i] = zone->watermark_boost;
+	}
+	boosted = nr_boost_reclaim;
+
+restart:
+	sc.priority = DEF_PRIORITY;
 	do {
 		unsigned long nr_reclaimed = sc.nr_reclaimed;
 		bool raise_priority = true;
+		bool balanced;
 		bool ret;
 
 		sc.reclaim_idx = classzone_idx;
@@ -3542,13 +3642,39 @@
 		}
 
 		/*
-		 * Only reclaim if there are no eligible zones. Note that
-		 * sc.reclaim_idx is not used as buffer_heads_over_limit may
-		 * have adjusted it.
+		 * If the pgdat is imbalanced then ignore boosting and preserve
+		 * the watermarks for a later time and restart. Note that the
+		 * zone watermarks will be still reset at the end of balancing
+		 * on the grounds that the normal reclaim should be enough to
+		 * re-evaluate if boosting is required when kswapd next wakes.
 		 */
-		if (pgdat_balanced(pgdat, sc.order, classzone_idx))
+		balanced = pgdat_balanced(pgdat, sc.order, classzone_idx);
+		if (!balanced && nr_boost_reclaim) {
+			nr_boost_reclaim = 0;
+			goto restart;
+		}
+
+		/*
+		 * If boosting is not active then only reclaim if there are no
+		 * eligible zones. Note that sc.reclaim_idx is not used as
+		 * buffer_heads_over_limit may have adjusted it.
+		 */
+		if (!nr_boost_reclaim && balanced)
 			goto out;
 
+		/* Limit the priority of boosting to avoid reclaim writeback */
+		if (nr_boost_reclaim && sc.priority == DEF_PRIORITY - 2)
+			raise_priority = false;
+
+		/*
+		 * Do not writeback or swap pages for boosted reclaim. The
+		 * intent is to relieve pressure not issue sub-optimal IO
+		 * from reclaim context. If no pages are reclaimed, the
+		 * reclaim will be aborted.
+		 */
+		sc.may_writepage = !laptop_mode && !nr_boost_reclaim;
+		sc.may_swap = !nr_boost_reclaim;
+
 		/*
 		 * Do some background aging of the anon list, to give
 		 * pages a chance to be referenced before reclaiming. All
@@ -3600,6 +3726,16 @@
 		 * progress in reclaiming pages
 		 */
 		nr_reclaimed = sc.nr_reclaimed - nr_reclaimed;
+		nr_boost_reclaim -= min(nr_boost_reclaim, nr_reclaimed);
+
+		/*
+		 * If reclaim made no progress for a boost, stop reclaim as
+		 * IO cannot be queued and it could be an infinite loop in
+		 * extreme circumstances.
+		 */
+		if (nr_boost_reclaim && !nr_reclaimed)
+			break;
+
 		if (raise_priority || !nr_reclaimed)
 			sc.priority--;
 	} while (sc.priority >= 1);
@@ -3608,8 +3744,33 @@
 		pgdat->kswapd_failures++;
 
 out:
+	/* If reclaim was boosted, account for the reclaim done in this pass */
+	if (boosted) {
+		unsigned long flags;
+
+		for (i = 0; i <= classzone_idx; i++) {
+			if (!zone_boosts[i])
+				continue;
+
+			/* Increments are under the zone lock */
+			zone = pgdat->node_zones + i;
+			spin_lock_irqsave(&zone->lock, flags);
+			zone->watermark_boost -= min(zone->watermark_boost, zone_boosts[i]);
+			spin_unlock_irqrestore(&zone->lock, flags);
+		}
+
+		/*
+		 * As there is now likely space, wakeup kcompact to defragment
+		 * pageblocks.
+		 */
+		wakeup_kcompactd(pgdat, pageblock_order, classzone_idx);
+	}
+
 	snapshot_refaults(NULL, pgdat);
 	__fs_reclaim_release();
+	psi_memstall_leave(&pflags);
+	set_task_reclaim_state(current, NULL);
+
 	/*
 	 * Return the order kswapd stopped reclaiming at as
 	 * prepare_kswapd_sleep() takes it into account. If another caller
@@ -3620,19 +3781,18 @@
 }
 
 /*
- * pgdat->kswapd_classzone_idx is the highest zone index that a recent
- * allocation request woke kswapd for. When kswapd has not woken recently,
- * the value is MAX_NR_ZONES which is not a valid index. This compares a
- * given classzone and returns it or the highest classzone index kswapd
- * was recently woke for.
+ * The pgdat->kswapd_classzone_idx is used to pass the highest zone index to be
+ * reclaimed by kswapd from the waker. If the value is MAX_NR_ZONES which is not
+ * a valid index then either kswapd runs for first time or kswapd couldn't sleep
+ * after previous reclaim attempt (node is still unbalanced). In that case
+ * return the zone index of the previous kswapd reclaim cycle.
  */
 static enum zone_type kswapd_classzone_idx(pg_data_t *pgdat,
-					   enum zone_type classzone_idx)
+					   enum zone_type prev_classzone_idx)
 {
 	if (pgdat->kswapd_classzone_idx == MAX_NR_ZONES)
-		return classzone_idx;
-
-	return max(pgdat->kswapd_classzone_idx, classzone_idx);
+		return prev_classzone_idx;
+	return pgdat->kswapd_classzone_idx;
 }
 
 static void kswapd_try_to_sleep(pg_data_t *pgdat, int alloc_order, int reclaim_order,
@@ -3734,15 +3894,10 @@
 	unsigned int classzone_idx = MAX_NR_ZONES - 1;
 	pg_data_t *pgdat = (pg_data_t*)p;
 	struct task_struct *tsk = current;
-
-	struct reclaim_state reclaim_state = {
-		.reclaimed_slab = 0,
-	};
 	const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
 
 	if (!cpumask_empty(cpumask))
 		set_cpus_allowed_ptr(tsk, cpumask);
-	current->reclaim_state = &reclaim_state;
 
 	/*
 	 * Tell the memory management that we're a "memory allocator",
@@ -3773,7 +3928,7 @@
 
 		/* Read the new order and classzone_idx */
 		alloc_order = reclaim_order = pgdat->kswapd_order;
-		classzone_idx = kswapd_classzone_idx(pgdat, 0);
+		classzone_idx = kswapd_classzone_idx(pgdat, classzone_idx);
 		pgdat->kswapd_order = 0;
 		pgdat->kswapd_classzone_idx = MAX_NR_ZONES;
 
@@ -3804,7 +3959,6 @@
 	}
 
 	tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD);
-	current->reclaim_state = NULL;
 
 	return 0;
 }
@@ -3827,15 +3981,20 @@
 	if (!cpuset_zone_allowed(zone, gfp_flags))
 		return;
 	pgdat = zone->zone_pgdat;
-	pgdat->kswapd_classzone_idx = kswapd_classzone_idx(pgdat,
-							   classzone_idx);
+
+	if (pgdat->kswapd_classzone_idx == MAX_NR_ZONES)
+		pgdat->kswapd_classzone_idx = classzone_idx;
+	else
+		pgdat->kswapd_classzone_idx = max(pgdat->kswapd_classzone_idx,
+						  classzone_idx);
 	pgdat->kswapd_order = max(pgdat->kswapd_order, order);
 	if (!waitqueue_active(&pgdat->kswapd_wait))
 		return;
 
 	/* Hopeless node, leave it to direct reclaim if possible */
 	if (pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES ||
-	    pgdat_balanced(pgdat, order, classzone_idx)) {
+	    (pgdat_balanced(pgdat, order, classzone_idx) &&
+	     !pgdat_watermark_boosted(pgdat, classzone_idx))) {
 		/*
 		 * There may be plenty of free memory available, but it's too
 		 * fragmented for high-order allocations.  Wake up kcompactd
@@ -3864,7 +4023,6 @@
  */
 unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
 {
-	struct reclaim_state reclaim_state;
 	struct scan_control sc = {
 		.nr_to_reclaim = nr_to_reclaim,
 		.gfp_mask = GFP_HIGHUSER_MOVABLE,
@@ -3876,18 +4034,16 @@
 		.hibernation_mode = 1,
 	};
 	struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
-	struct task_struct *p = current;
 	unsigned long nr_reclaimed;
 	unsigned int noreclaim_flag;
 
 	fs_reclaim_acquire(sc.gfp_mask);
 	noreclaim_flag = memalloc_noreclaim_save();
-	reclaim_state.reclaimed_slab = 0;
-	p->reclaim_state = &reclaim_state;
+	set_task_reclaim_state(current, &sc.reclaim_state);
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
-	p->reclaim_state = NULL;
+	set_task_reclaim_state(current, NULL);
 	memalloc_noreclaim_restore(noreclaim_flag);
 	fs_reclaim_release(sc.gfp_mask);
 
@@ -4052,7 +4208,6 @@
 	/* Minimum pages needed in order to stay on node */
 	const unsigned long nr_pages = 1 << order;
 	struct task_struct *p = current;
-	struct reclaim_state reclaim_state;
 	unsigned int noreclaim_flag;
 	struct scan_control sc = {
 		.nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX),
@@ -4065,6 +4220,9 @@
 		.reclaim_idx = gfp_zone(gfp_mask),
 	};
 
+	trace_mm_vmscan_node_reclaim_begin(pgdat->node_id, order,
+					   sc.gfp_mask);
+
 	cond_resched();
 	fs_reclaim_acquire(sc.gfp_mask);
 	/*
@@ -4074,8 +4232,7 @@
 	 */
 	noreclaim_flag = memalloc_noreclaim_save();
 	p->flags |= PF_SWAPWRITE;
-	reclaim_state.reclaimed_slab = 0;
-	p->reclaim_state = &reclaim_state;
+	set_task_reclaim_state(p, &sc.reclaim_state);
 
 	if (node_pagecache_reclaimable(pgdat) > pgdat->min_unmapped_pages) {
 		/*
@@ -4087,10 +4244,13 @@
 		} while (sc.nr_reclaimed < nr_pages && --sc.priority >= 0);
 	}
 
-	p->reclaim_state = NULL;
+	set_task_reclaim_state(p, NULL);
 	current->flags &= ~PF_SWAPWRITE;
 	memalloc_noreclaim_restore(noreclaim_flag);
 	fs_reclaim_release(sc.gfp_mask);
+
+	trace_mm_vmscan_node_reclaim_end(sc.nr_reclaimed);
+
 	return sc.nr_reclaimed >= nr_pages;
 }
 
@@ -4163,17 +4323,16 @@
 	return ret;
 }
 
-#ifdef CONFIG_SHMEM
 /**
- * check_move_unevictable_pages - check pages for evictability and move to appropriate zone lru list
- * @pages:	array of pages to check
- * @nr_pages:	number of pages to check
+ * check_move_unevictable_pages - check pages for evictability and move to
+ * appropriate zone lru list
+ * @pvec: pagevec with lru pages to check
  *
- * Checks pages for evictability and moves them to the appropriate lru list.
- *
- * This function is only used for SysV IPC SHM_UNLOCK.
+ * Checks pages for evictability, if an evictable page is in the unevictable
+ * lru list, moves it to the appropriate evictable lru list. This function
+ * should be only used for lru pages.
  */
-void check_move_unevictable_pages(struct page **pages, int nr_pages)
+void check_move_unevictable_pages(struct pagevec *pvec)
 {
 	struct lruvec *lruvec;
 	struct pglist_data *pgdat = NULL;
@@ -4181,8 +4340,8 @@
 	int pgrescued = 0;
 	int i;
 
-	for (i = 0; i < nr_pages; i++) {
-		struct page *page = pages[i];
+	for (i = 0; i < pvec->nr; i++) {
+		struct page *page = pvec->pages[i];
 		struct pglist_data *pagepgdat = page_pgdat(page);
 
 		pgscanned++;
@@ -4214,4 +4373,4 @@
 		spin_unlock_irq(&pgdat->lru_lock);
 	}
 }
-#endif /* CONFIG_SHMEM */
+EXPORT_SYMBOL_GPL(check_move_unevictable_pages);