1 files changed, 68 insertions, 22 deletions
diff --git a/mm/swap.c b/mm/swap.c
index 10decd9dffa1..b81cce146eb2 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -45,7 +45,7 @@
 
 /* How many pages do we try to swap or page in/out together? As a power of 2 */
 int page_cluster;
-const int page_cluster_max = 31;
+static const int page_cluster_max = 31;
 
 struct cpu_fbatches {
 	/*
@@ -109,7 +109,7 @@ void __folio_put(struct folio *folio)
 	page_cache_release(folio);
 	folio_unqueue_deferred_split(folio);
 	mem_cgroup_uncharge(folio);
-	free_unref_page(&folio->page, folio_order(folio));
+	free_frozen_pages(&folio->page, folio_order(folio));
 }
 EXPORT_SYMBOL(__folio_put);
 
@@ -379,37 +379,58 @@ static void __lru_cache_activate_folio(struct folio *folio)
 }
 
 #ifdef CONFIG_LRU_GEN
-static void folio_inc_refs(struct folio *folio)
+
+static void lru_gen_inc_refs(struct folio *folio)
 {
 	unsigned long new_flags, old_flags = READ_ONCE(folio->flags);
 
 	if (folio_test_unevictable(folio))
 		return;
 
+	/* see the comment on LRU_REFS_FLAGS */
 	if (!folio_test_referenced(folio)) {
-		folio_set_referenced(folio);
-		return;
-	}
-
-	if (!folio_test_workingset(folio)) {
-		folio_set_workingset(folio);
+		set_mask_bits(&folio->flags, LRU_REFS_MASK, BIT(PG_referenced));
 		return;
 	}
 
-	/* see the comment on MAX_NR_TIERS */
 	do {
-		new_flags = old_flags & LRU_REFS_MASK;
-		if (new_flags == LRU_REFS_MASK)
-			break;
+		if ((old_flags & LRU_REFS_MASK) == LRU_REFS_MASK) {
+			if (!folio_test_workingset(folio))
+				folio_set_workingset(folio);
+			return;
+		}
 
-		new_flags += BIT(LRU_REFS_PGOFF);
-		new_flags |= old_flags & ~LRU_REFS_MASK;
+		new_flags = old_flags + BIT(LRU_REFS_PGOFF);
 	} while (!try_cmpxchg(&folio->flags, &old_flags, new_flags));
 }
-#else
-static void folio_inc_refs(struct folio *folio)
+
+static bool lru_gen_clear_refs(struct folio *folio)
+{
+	struct lru_gen_folio *lrugen;
+	int gen = folio_lru_gen(folio);
+	int type = folio_is_file_lru(folio);
+
+	if (gen < 0)
+		return true;
+
+	set_mask_bits(&folio->flags, LRU_REFS_FLAGS | BIT(PG_workingset), 0);
+
+	lrugen = &folio_lruvec(folio)->lrugen;
+	/* whether can do without shuffling under the LRU lock */
+	return gen == lru_gen_from_seq(READ_ONCE(lrugen->min_seq[type]));
+}
+
+#else /* !CONFIG_LRU_GEN */
+
+static void lru_gen_inc_refs(struct folio *folio)
+{
+}
+
+static bool lru_gen_clear_refs(struct folio *folio)
 {
+	return false;
 }
+
 #endif /* CONFIG_LRU_GEN */
 
 /**
@@ -427,8 +448,10 @@ static void folio_inc_refs(struct folio *folio)
  */
 void folio_mark_accessed(struct folio *folio)
 {
+	if (folio_test_dropbehind(folio))
+		return;
 	if (lru_gen_enabled()) {
-		folio_inc_refs(folio);
+		lru_gen_inc_refs(folio);
 		return;
 	}
 
@@ -474,7 +497,7 @@ void folio_add_lru(struct folio *folio)
 			folio_test_unevictable(folio), folio);
 	VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
 
-	/* see the comment in lru_gen_add_folio() */
+	/* see the comment in lru_gen_folio_seq() */
 	if (lru_gen_enabled() && !folio_test_unevictable(folio) &&
 	    lru_gen_in_fault() && !(current->flags & PF_MEMALLOC))
 		folio_set_active(folio);
@@ -524,7 +547,7 @@ void folio_add_lru_vma(struct folio *folio, struct vm_area_struct *vma)
  */
 static void lru_deactivate_file(struct lruvec *lruvec, struct folio *folio)
 {
-	bool active = folio_test_active(folio);
+	bool active = folio_test_active(folio) || lru_gen_enabled();
 	long nr_pages = folio_nr_pages(folio);
 
 	if (folio_test_unevictable(folio))
@@ -589,7 +612,10 @@ static void lru_lazyfree(struct lruvec *lruvec, struct folio *folio)
 
 	lruvec_del_folio(lruvec, folio);
 	folio_clear_active(folio);
-	folio_clear_referenced(folio);
+	if (lru_gen_enabled())
+		lru_gen_clear_refs(folio);
+	else
+		folio_clear_referenced(folio);
 	/*
 	 * Lazyfree folios are clean anonymous folios.  They have
 	 * the swapbacked flag cleared, to distinguish them from normal
@@ -657,6 +683,9 @@ void deactivate_file_folio(struct folio *folio)
 	if (folio_test_unevictable(folio))
 		return;
 
+	if (lru_gen_enabled() && lru_gen_clear_refs(folio))
+		return;
+
 	folio_batch_add_and_move(folio, lru_deactivate_file, true);
 }
 
@@ -670,7 +699,10 @@ void deactivate_file_folio(struct folio *folio)
  */
 void folio_deactivate(struct folio *folio)
 {
-	if (folio_test_unevictable(folio) || !(folio_test_active(folio) || lru_gen_enabled()))
+	if (folio_test_unevictable(folio))
+		return;
+
+	if (lru_gen_enabled() ? lru_gen_clear_refs(folio) : !folio_test_active(folio))
 		return;
 
 	folio_batch_add_and_move(folio, lru_deactivate, true);
@@ -1044,6 +1076,18 @@ void folio_batch_remove_exceptionals(struct folio_batch *fbatch)
 	fbatch->nr = j;
 }
 
+static const struct ctl_table swap_sysctl_table[] = {
+	{
+		.procname	= "page-cluster",
+		.data		= &page_cluster,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= (void *)&page_cluster_max,
+	}
+};
+
 /*
  * Perform any setup for the swap system
  */
@@ -1060,4 +1104,6 @@ void __init swap_setup(void)
 	 * Right now other parts of the system means that we
 	 * _really_ don't want to cluster much more
 	 */
+
+	register_sysctl_init("vm", swap_sysctl_table);
 }