1 files changed, 307 insertions, 103 deletions

diff --git a/mm/workingset.c b/mm/workingset.c
index 975a4d2dd02e..226012974328 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -111,9 +111,20 @@
  *
  *   NR_inactive + (R - E) <= NR_inactive + NR_active
  *
- * which can be further simplified to
+ * If we have swap we should consider about NR_inactive_anon and
+ * NR_active_anon, so for page cache and anonymous respectively:
  *
- *   (R - E) <= NR_active
+ *   NR_inactive_file + (R - E) <= NR_inactive_file + NR_active_file
+ *   + NR_inactive_anon + NR_active_anon
+ *
+ *   NR_inactive_anon + (R - E) <= NR_inactive_anon + NR_active_anon
+ *   + NR_inactive_file + NR_active_file
+ *
+ * Which can be further simplified to:
+ *
+ *   (R - E) <= NR_active_file + NR_inactive_anon + NR_active_anon
+ *
+ *   (R - E) <= NR_active_anon + NR_inactive_file + NR_active_file
  *
  * Put into words, the refault distance (out-of-cache) can be seen as
  * a deficit in inactive list space (in-cache).  If the inactive list
@@ -130,14 +141,14 @@
  * are no longer in active use.
  *
  * So when a refault distance of (R - E) is observed and there are at
- * least (R - E) active pages, the refaulting page is activated
- * optimistically in the hope that (R - E) active pages are actually
+ * least (R - E) pages in the userspace workingset, the refaulting page
+ * is activated optimistically in the hope that (R - E) pages are actually
  * used less frequently than the refaulting page - or even not used at
  * all anymore.
  *
  * That means if inactive cache is refaulting with a suitable refault
  * distance, we assume the cache workingset is transitioning and put
- * pressure on the current active list.
+ * pressure on the current workingset.
  *
  * If this is wrong and demotion kicks in, the pages which are truly
  * used more frequently will be reactivated while the less frequently
@@ -168,8 +179,10 @@
  * refault distance will immediately activate the refaulting page.
  */
 
+#define WORKINGSET_SHIFT 1
 #define EVICTION_SHIFT	((BITS_PER_LONG - BITS_PER_XA_VALUE) +	\
-			 1 + NODES_SHIFT + MEM_CGROUP_ID_SHIFT)
+			 WORKINGSET_SHIFT + NODES_SHIFT + \
+			 MEM_CGROUP_ID_SHIFT)
 #define EVICTION_MASK	(~0UL >> EVICTION_SHIFT)
 
 /*
@@ -185,11 +198,10 @@ static unsigned int bucket_order __read_mostly;
 static void *pack_shadow(int memcgid, pg_data_t *pgdat, unsigned long eviction,
 			 bool workingset)
 {
-	eviction >>= bucket_order;
 	eviction &= EVICTION_MASK;
 	eviction = (eviction << MEM_CGROUP_ID_SHIFT) | memcgid;
 	eviction = (eviction << NODES_SHIFT) | pgdat->node_id;
-	eviction = (eviction << 1) | workingset;
+	eviction = (eviction << WORKINGSET_SHIFT) | workingset;
 
 	return xa_mk_value(eviction);
 }
@@ -201,8 +213,8 @@ static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat,
 	int memcgid, nid;
 	bool workingset;
 
-	workingset = entry & 1;
-	entry >>= 1;
+	workingset = entry & ((1UL << WORKINGSET_SHIFT) - 1);
+	entry >>= WORKINGSET_SHIFT;
 	nid = entry & ((1UL << NODES_SHIFT) - 1);
 	entry >>= NODES_SHIFT;
 	memcgid = entry & ((1UL << MEM_CGROUP_ID_SHIFT) - 1);
@@ -210,10 +222,126 @@ static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat,
 
 	*memcgidp = memcgid;
 	*pgdat = NODE_DATA(nid);
-	*evictionp = entry << bucket_order;
+	*evictionp = entry;
 	*workingsetp = workingset;
 }
 
+#ifdef CONFIG_LRU_GEN
+
+static void *lru_gen_eviction(struct folio *folio)
+{
+	int hist;
+	unsigned long token;
+	unsigned long min_seq;
+	struct lruvec *lruvec;
+	struct lru_gen_folio *lrugen;
+	int type = folio_is_file_lru(folio);
+	int delta = folio_nr_pages(folio);
+	int refs = folio_lru_refs(folio);
+	int tier = lru_tier_from_refs(refs);
+	struct mem_cgroup *memcg = folio_memcg(folio);
+	struct pglist_data *pgdat = folio_pgdat(folio);
+
+	BUILD_BUG_ON(LRU_GEN_WIDTH + LRU_REFS_WIDTH > BITS_PER_LONG - EVICTION_SHIFT);
+
+	lruvec = mem_cgroup_lruvec(memcg, pgdat);
+	lrugen = &lruvec->lrugen;
+	min_seq = READ_ONCE(lrugen->min_seq[type]);
+	token = (min_seq << LRU_REFS_WIDTH) | max(refs - 1, 0);
+
+	hist = lru_hist_from_seq(min_seq);
+	atomic_long_add(delta, &lrugen->evicted[hist][type][tier]);
+
+	return pack_shadow(mem_cgroup_id(memcg), pgdat, token, refs);
+}
+
+/*
+ * Tests if the shadow entry is for a folio that was recently evicted.
+ * Fills in @lruvec, @token, @workingset with the values unpacked from shadow.
+ */
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+				unsigned long *token, bool *workingset)
+{
+	int memcg_id;
+	unsigned long min_seq;
+	struct mem_cgroup *memcg;
+	struct pglist_data *pgdat;
+
+	unpack_shadow(shadow, &memcg_id, &pgdat, token, workingset);
+
+	memcg = mem_cgroup_from_id(memcg_id);
+	*lruvec = mem_cgroup_lruvec(memcg, pgdat);
+
+	min_seq = READ_ONCE((*lruvec)->lrugen.min_seq[file]);
+	return (*token >> LRU_REFS_WIDTH) == (min_seq & (EVICTION_MASK >> LRU_REFS_WIDTH));
+}
+
+static void lru_gen_refault(struct folio *folio, void *shadow)
+{
+	bool recent;
+	int hist, tier, refs;
+	bool workingset;
+	unsigned long token;
+	struct lruvec *lruvec;
+	struct lru_gen_folio *lrugen;
+	int type = folio_is_file_lru(folio);
+	int delta = folio_nr_pages(folio);
+
+	rcu_read_lock();
+
+	recent = lru_gen_test_recent(shadow, type, &lruvec, &token, &workingset);
+	if (lruvec != folio_lruvec(folio))
+		goto unlock;
+
+	mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + type, delta);
+
+	if (!recent)
+		goto unlock;
+
+	lrugen = &lruvec->lrugen;
+
+	hist = lru_hist_from_seq(READ_ONCE(lrugen->min_seq[type]));
+	/* see the comment in folio_lru_refs() */
+	refs = (token & (BIT(LRU_REFS_WIDTH) - 1)) + workingset;
+	tier = lru_tier_from_refs(refs);
+
+	atomic_long_add(delta, &lrugen->refaulted[hist][type][tier]);
+	mod_lruvec_state(lruvec, WORKINGSET_ACTIVATE_BASE + type, delta);
+
+	/*
+	 * Count the following two cases as stalls:
+	 * 1. For pages accessed through page tables, hotter pages pushed out
+	 *    hot pages which refaulted immediately.
+	 * 2. For pages accessed multiple times through file descriptors,
+	 *    they would have been protected by sort_folio().
+	 */
+	if (lru_gen_in_fault() || refs >= BIT(LRU_REFS_WIDTH) - 1) {
+		set_mask_bits(&folio->flags, 0, LRU_REFS_MASK | BIT(PG_workingset));
+		mod_lruvec_state(lruvec, WORKINGSET_RESTORE_BASE + type, delta);
+	}
+unlock:
+	rcu_read_unlock();
+}
+
+#else /* !CONFIG_LRU_GEN */
+
+static void *lru_gen_eviction(struct folio *folio)
+{
+	return NULL;
+}
+
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+				unsigned long *token, bool *workingset)
+{
+	return false;
+}
+
+static void lru_gen_refault(struct folio *folio, void *shadow)
+{
+}
+
+#endif /* CONFIG_LRU_GEN */
+
 /**
  * workingset_age_nonresident - age non-resident entries as LRU ages
  * @lruvec: the lruvec that was aged
@@ -243,66 +371,80 @@ void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages)
 }
 
 /**
- * workingset_eviction - note the eviction of a page from memory
+ * workingset_eviction - note the eviction of a folio from memory
  * @target_memcg: the cgroup that is causing the reclaim
- * @page: the page being evicted
+ * @folio: the folio being evicted
  *
- * Returns a shadow entry to be stored in @page->mapping->i_pages in place
- * of the evicted @page so that a later refault can be detected.
+ * Return: a shadow entry to be stored in @folio->mapping->i_pages in place
+ * of the evicted @folio so that a later refault can be detected.
  */
-void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg)
+void *workingset_eviction(struct folio *folio, struct mem_cgroup *target_memcg)
 {
-	struct pglist_data *pgdat = page_pgdat(page);
+	struct pglist_data *pgdat = folio_pgdat(folio);
 	unsigned long eviction;
 	struct lruvec *lruvec;
 	int memcgid;
 
-	/* Page is fully exclusive and pins page->mem_cgroup */
-	VM_BUG_ON_PAGE(PageLRU(page), page);
-	VM_BUG_ON_PAGE(page_count(page), page);
-	VM_BUG_ON_PAGE(!PageLocked(page), page);
+	/* Folio is fully exclusive and pins folio's memory cgroup pointer */
+	VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
+	VM_BUG_ON_FOLIO(folio_ref_count(folio), folio);
+	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
+
+	if (lru_gen_enabled())
+		return lru_gen_eviction(folio);
 
 	lruvec = mem_cgroup_lruvec(target_memcg, pgdat);
-	workingset_age_nonresident(lruvec, thp_nr_pages(page));
 	/* XXX: target_memcg can be NULL, go through lruvec */
 	memcgid = mem_cgroup_id(lruvec_memcg(lruvec));
 	eviction = atomic_long_read(&lruvec->nonresident_age);
-	return pack_shadow(memcgid, pgdat, eviction, PageWorkingset(page));
+	eviction >>= bucket_order;
+	workingset_age_nonresident(lruvec, folio_nr_pages(folio));
+	return pack_shadow(memcgid, pgdat, eviction,
+				folio_test_workingset(folio));
 }
 
 /**
- * workingset_refault - evaluate the refault of a previously evicted page
- * @page: the freshly allocated replacement page
- * @shadow: shadow entry of the evicted page
- *
- * Calculates and evaluates the refault distance of the previously
- * evicted page in the context of the node and the memcg whose memory
- * pressure caused the eviction.
+ * workingset_test_recent - tests if the shadow entry is for a folio that was
+ * recently evicted. Also fills in @workingset with the value unpacked from
+ * shadow.
+ * @shadow: the shadow entry to be tested.
+ * @file: whether the corresponding folio is from the file lru.
+ * @workingset: where the workingset value unpacked from shadow should
+ * be stored.
+ *
+ * Return: true if the shadow is for a recently evicted folio; false otherwise.
  */
-void workingset_refault(struct page *page, void *shadow)
+bool workingset_test_recent(void *shadow, bool file, bool *workingset)
 {
-	bool file = page_is_file_lru(page);
 	struct mem_cgroup *eviction_memcg;
 	struct lruvec *eviction_lruvec;
 	unsigned long refault_distance;
 	unsigned long workingset_size;
-	struct pglist_data *pgdat;
-	struct mem_cgroup *memcg;
-	unsigned long eviction;
-	struct lruvec *lruvec;
 	unsigned long refault;
-	bool workingset;
 	int memcgid;
-
-	unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset);
+	struct pglist_data *pgdat;
+	unsigned long eviction;
 
 	rcu_read_lock();
+
+	if (lru_gen_enabled()) {
+		bool recent = lru_gen_test_recent(shadow, file,
+				&eviction_lruvec, &eviction, workingset);
+
+		rcu_read_unlock();
+		return recent;
+	}
+
+
+	unpack_shadow(shadow, &memcgid, &pgdat, &eviction, workingset);
+	eviction <<= bucket_order;
+
 	/*
 	 * Look up the memcg associated with the stored ID. It might
-	 * have been deleted since the page's eviction.
+	 * have been deleted since the folio's eviction.
 	 *
 	 * Note that in rare events the ID could have been recycled
-	 * for a new cgroup that refaults a shared page. This is
+	 * for a new cgroup that refaults a shared folio. This is
 	 * impossible to tell from the available data. However, this
 	 * should be a rare and limited disturbance, and activations
 	 * are always speculative anyway. Ultimately, it's the aging
@@ -314,8 +456,21 @@ void workingset_refault(struct page *page, void *shadow)
 	 * configurations instead.
 	 */
 	eviction_memcg = mem_cgroup_from_id(memcgid);
-	if (!mem_cgroup_disabled() && !eviction_memcg)
-		goto out;
+	if (!mem_cgroup_disabled() &&
+	    (!eviction_memcg || !mem_cgroup_tryget(eviction_memcg))) {
+		rcu_read_unlock();
+		return false;
+	}
+
+	rcu_read_unlock();
+
+	/*
+	 * Flush stats (and potentially sleep) outside the RCU read section.
+	 * XXX: With per-memcg flushing and thresholding, is ratelimiting
+	 * still needed here?
+	 */
+	mem_cgroup_flush_stats_ratelimited(eviction_memcg);
+
 	eviction_lruvec = mem_cgroup_lruvec(eviction_memcg, pgdat);
 	refault = atomic_long_read(&eviction_lruvec->nonresident_age);
 
@@ -338,31 +493,18 @@ void workingset_refault(struct page *page, void *shadow)
 	refault_distance = (refault - eviction) & EVICTION_MASK;
 
 	/*
-	 * The activation decision for this page is made at the level
-	 * where the eviction occurred, as that is where the LRU order
-	 * during page reclaim is being determined.
-	 *
-	 * However, the cgroup that will own the page is the one that
-	 * is actually experiencing the refault event.
-	 */
-	memcg = page_memcg(page);
-	lruvec = mem_cgroup_lruvec(memcg, pgdat);
-
-	inc_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file);
-
-	/*
 	 * Compare the distance to the existing workingset size. We
 	 * don't activate pages that couldn't stay resident even if
 	 * all the memory was available to the workingset. Whether
 	 * workingset competition needs to consider anon or not depends
-	 * on having swap.
+	 * on having free swap space.
 	 */
 	workingset_size = lruvec_page_state(eviction_lruvec, NR_ACTIVE_FILE);
 	if (!file) {
 		workingset_size += lruvec_page_state(eviction_lruvec,
 						     NR_INACTIVE_FILE);
 	}
-	if (mem_cgroup_get_nr_swap_pages(memcg) > 0) {
+	if (mem_cgroup_get_nr_swap_pages(eviction_memcg) > 0) {
 		workingset_size += lruvec_page_state(eviction_lruvec,
 						     NR_ACTIVE_ANON);
 		if (file) {
@@ -370,34 +512,77 @@ void workingset_refault(struct page *page, void *shadow)
 						     NR_INACTIVE_ANON);
 		}
 	}
-	if (refault_distance > workingset_size)
-		goto out;
 
-	SetPageActive(page);
-	workingset_age_nonresident(lruvec, thp_nr_pages(page));
-	inc_lruvec_state(lruvec, WORKINGSET_ACTIVATE_BASE + file);
+	mem_cgroup_put(eviction_memcg);
+	return refault_distance <= workingset_size;
+}
+
+/**
+ * workingset_refault - Evaluate the refault of a previously evicted folio.
+ * @folio: The freshly allocated replacement folio.
+ * @shadow: Shadow entry of the evicted folio.
+ *
+ * Calculates and evaluates the refault distance of the previously
+ * evicted folio in the context of the node and the memcg whose memory
+ * pressure caused the eviction.
+ */
+void workingset_refault(struct folio *folio, void *shadow)
+{
+	bool file = folio_is_file_lru(folio);
+	struct pglist_data *pgdat;
+	struct mem_cgroup *memcg;
+	struct lruvec *lruvec;
+	bool workingset;
+	long nr;
+
+	if (lru_gen_enabled()) {
+		lru_gen_refault(folio, shadow);
+		return;
+	}
+
+	/*
+	 * The activation decision for this folio is made at the level
+	 * where the eviction occurred, as that is where the LRU order
+	 * during folio reclaim is being determined.
+	 *
+	 * However, the cgroup that will own the folio is the one that
+	 * is actually experiencing the refault event. Make sure the folio is
+	 * locked to guarantee folio_memcg() stability throughout.
+	 */
+	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
+	nr = folio_nr_pages(folio);
+	memcg = folio_memcg(folio);
+	pgdat = folio_pgdat(folio);
+	lruvec = mem_cgroup_lruvec(memcg, pgdat);
 
-	/* Page was active prior to eviction */
+	mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr);
+
+	if (!workingset_test_recent(shadow, file, &workingset))
+		return;
+
+	folio_set_active(folio);
+	workingset_age_nonresident(lruvec, nr);
+	mod_lruvec_state(lruvec, WORKINGSET_ACTIVATE_BASE + file, nr);
+
+	/* Folio was active prior to eviction */
 	if (workingset) {
-		SetPageWorkingset(page);
-		/* XXX: Move to lru_cache_add() when it supports new vs putback */
-		spin_lock_irq(&page_pgdat(page)->lru_lock);
-		lru_note_cost_page(page);
-		spin_unlock_irq(&page_pgdat(page)->lru_lock);
-		inc_lruvec_state(lruvec, WORKINGSET_RESTORE_BASE + file);
+		folio_set_workingset(folio);
+		/*
+		 * XXX: Move to folio_add_lru() when it supports new vs
+		 * putback
+		 */
+		lru_note_cost_refault(folio);
+		mod_lruvec_state(lruvec, WORKINGSET_RESTORE_BASE + file, nr);
 	}
-out:
-	rcu_read_unlock();
 }
 
 /**
  * workingset_activation - note a page activation
- * @page: page that is being activated
+ * @folio: Folio that is being activated.
  */
-void workingset_activation(struct page *page)
+void workingset_activation(struct folio *folio)
 {
 	struct mem_cgroup *memcg;
-	struct lruvec *lruvec;
 
 	rcu_read_lock();
 	/*
@@ -407,11 +592,10 @@ void workingset_activation(struct page *page)
 	 * XXX: See workingset_refault() - this should return
 	 * root_mem_cgroup even for !CONFIG_MEMCG.
 	 */
-	memcg = page_memcg_rcu(page);
+	memcg = folio_memcg_rcu(folio);
 	if (!mem_cgroup_disabled() && !memcg)
 		goto out;
-	lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
-	workingset_age_nonresident(lruvec, thp_nr_pages(page));
+	workingset_age_nonresident(folio_lruvec(folio), folio_nr_pages(folio));
 out:
 	rcu_read_unlock();
 }
@@ -428,10 +612,12 @@ out:
  * point where they would still be useful.
  */
 
-static struct list_lru shadow_nodes;
+struct list_lru shadow_nodes;
 
 void workingset_update_node(struct xa_node *node)
 {
+	struct address_space *mapping;
+
 	/*
 	 * Track non-empty nodes that contain only shadow entries;
 	 * unlink those that contain pages or are being freed.
@@ -440,17 +626,18 @@ void workingset_update_node(struct xa_node *node)
 	 * already where they should be. The list_empty() test is safe
 	 * as node->private_list is protected by the i_pages lock.
 	 */
-	VM_WARN_ON_ONCE(!irqs_disabled());  /* For __inc_lruvec_page_state */
+	mapping = container_of(node->array, struct address_space, i_pages);
+	lockdep_assert_held(&mapping->i_pages.xa_lock);
 
 	if (node->count && node->count == node->nr_values) {
 		if (list_empty(&node->private_list)) {
-			list_lru_add(&shadow_nodes, &node->private_list);
-			__inc_lruvec_slab_state(node, WORKINGSET_NODES);
+			list_lru_add_obj(&shadow_nodes, &node->private_list);
+			__inc_lruvec_kmem_state(node, WORKINGSET_NODES);
 		}
 	} else {
 		if (!list_empty(&node->private_list)) {
-			list_lru_del(&shadow_nodes, &node->private_list);
-			__dec_lruvec_slab_state(node, WORKINGSET_NODES);
+			list_lru_del_obj(&shadow_nodes, &node->private_list);
+			__dec_lruvec_kmem_state(node, WORKINGSET_NODES);
 		}
 	}
 }
@@ -463,6 +650,8 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
 	unsigned long pages;
 
 	nodes = list_lru_shrink_count(&shadow_nodes, sc);
+	if (!nodes)
+		return SHRINK_EMPTY;
 
 	/*
 	 * Approximate a reasonable limit for the nodes
@@ -491,6 +680,7 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
 		struct lruvec *lruvec;
 		int i;
 
+		mem_cgroup_flush_stats_ratelimited(sc->memcg);
 		lruvec = mem_cgroup_lruvec(sc->memcg, NODE_DATA(sc->nid));
 		for (pages = 0, i = 0; i < NR_LRU_LISTS; i++)
 			pages += lruvec_page_state_local(lruvec,
@@ -505,9 +695,6 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
 
 	max_nodes = pages >> (XA_CHUNK_SHIFT - 3);
 
-	if (!nodes)
-		return SHRINK_EMPTY;
-
 	if (nodes <= max_nodes)
 		return 0;
 	return nodes - max_nodes;
@@ -543,8 +730,18 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 		goto out;
 	}
 
+	/* For page cache we need to hold i_lock */
+	if (mapping->host != NULL) {
+		if (!spin_trylock(&mapping->host->i_lock)) {
+			xa_unlock(&mapping->i_pages);
+			spin_unlock_irq(lru_lock);
+			ret = LRU_RETRY;
+			goto out;
+		}
+	}
+
 	list_lru_isolate(lru, item);
-	__dec_lruvec_slab_state(node, WORKINGSET_NODES);
+	__dec_lruvec_kmem_state(node, WORKINGSET_NODES);
 
 	spin_unlock(lru_lock);
 
@@ -557,12 +754,16 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 		goto out_invalid;
 	if (WARN_ON_ONCE(node->count != node->nr_values))
 		goto out_invalid;
-	mapping->nrexceptional -= node->nr_values;
 	xa_delete_node(node, workingset_update_node);
-	__inc_lruvec_slab_state(node, WORKINGSET_NODERECLAIM);
+	__inc_lruvec_kmem_state(node, WORKINGSET_NODERECLAIM);
 
 out_invalid:
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping->host != NULL) {
+		if (mapping_shrinkable(mapping))
+			inode_add_lru(mapping->host);
+		spin_unlock(&mapping->host->i_lock);
+	}
 	ret = LRU_REMOVED_RETRY;
 out:
 	cond_resched();
@@ -578,13 +779,6 @@ static unsigned long scan_shadow_nodes(struct shrinker *shrinker,
 					NULL);
 }
 
-static struct shrinker workingset_shadow_shrinker = {
-	.count_objects = count_shadow_nodes,
-	.scan_objects = scan_shadow_nodes,
-	.seeks = 0, /* ->count reports only fully expendable nodes */
-	.flags = SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE,
-};
-
 /*
  * Our list_lru->lock is IRQ-safe as it nests inside the IRQ-safe
  * i_pages lock.
@@ -593,9 +787,10 @@ static struct lock_class_key shadow_nodes_key;
 
 static int __init workingset_init(void)
 {
+	struct shrinker *workingset_shadow_shrinker;
 	unsigned int timestamp_bits;
 	unsigned int max_order;
-	int ret;
+	int ret = -ENOMEM;
 
 	BUILD_BUG_ON(BITS_PER_LONG < EVICTION_SHIFT);
 	/*
@@ -612,17 +807,26 @@ static int __init workingset_init(void)
 	pr_info("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",
 	       timestamp_bits, max_order, bucket_order);
 
-	ret = prealloc_shrinker(&workingset_shadow_shrinker);
-	if (ret)
+	workingset_shadow_shrinker = shrinker_alloc(SHRINKER_NUMA_AWARE |
+						    SHRINKER_MEMCG_AWARE,
+						    "mm-shadow");
+	if (!workingset_shadow_shrinker)
 		goto err;
+
 	ret = __list_lru_init(&shadow_nodes, true, &shadow_nodes_key,
-			      &workingset_shadow_shrinker);
+			      workingset_shadow_shrinker);
 	if (ret)
 		goto err_list_lru;
-	register_shrinker_prepared(&workingset_shadow_shrinker);
+
+	workingset_shadow_shrinker->count_objects = count_shadow_nodes;
+	workingset_shadow_shrinker->scan_objects = scan_shadow_nodes;
+	/* ->count reports only fully expendable nodes */
+	workingset_shadow_shrinker->seeks = 0;
+
+	shrinker_register(workingset_shadow_shrinker);
 	return 0;
 err_list_lru:
-	free_prealloced_shrinker(&workingset_shadow_shrinker);
+	shrinker_free(workingset_shadow_shrinker);
 err:
 	return ret;
 }