mm-multi-gen-lru-use-pteppmdp_clear_young_notify.patch removed from -mm tree

The quilt patch titled
Subject: mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
has been removed from the -mm tree. Its filename was
mm-multi-gen-lru-use-pteppmdp_clear_young_notify.patch

This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Yu Zhao <[email protected]>
Subject: mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
Date: Sat, 19 Oct 2024 01:29:39 +0000

When the MM_WALK capability is enabled, memory that is mostly accessed by a VM appears younger than it really is, therefore this memory will be less likely to be evicted. Therefore, the presence of a running VM can significantly increase swap-outs for non-VM memory, regressing the performance for the rest of the system.

Fix this regression by always calling {ptep,pmdp}_clear_young_notify() whenever we clear the young bits on PMDs/PTEs.

---

 include/linux/mmzone.h |    5 +-
 mm/rmap.c              |    9 +--
 mm/vmscan.c            |   91 +++++++++++++++++++++------------------
 3 files changed, 55 insertions(+), 50 deletions(-)

@@ -555,7 +555,7 @@ struct lru_gen_memcg {
 
 void lru_gen_init_pgdat(struct pglist_data *pgdat);
 void lru_gen_init_lruvec(struct lruvec *lruvec);
-void lru_gen_look_around(struct page_vma_mapped_walk *pvmw);
+bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw);
 
 void lru_gen_init_memcg(struct mem_cgroup *memcg);
 void lru_gen_exit_memcg(struct mem_cgroup *memcg);

@@ -574,8 +574,9 @@ static inline void lru_gen_init_lruvec(s
 {
 }
 
-static inline void lru_gen_look_around(struct page_vma_mapped_walk *pvmw)
+static inline bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw)
 {
+	return false;
 }
 
 static inline void lru_gen_init_memcg(struct mem_cgroup *memcg)

@@ -885,13 +885,10 @@ static bool folio_referenced_one(struct
 			return false;
 		}
 
-		if (pvmw.pte) {
-			if (lru_gen_enabled() &&
-			    pte_young(ptep_get(pvmw.pte))) {
-				lru_gen_look_around(&pvmw);
+		if (lru_gen_enabled() && pvmw.pte) {
+			if (lru_gen_look_around(&pvmw))
 				referenced++;
-			}
-
+		} else if (pvmw.pte) {
 			if (ptep_clear_flush_young_notify(vma, address,
 						pvmw.pte))
 				referenced++;

_

Patches currently in -mm which might be from [email protected] are

mm-page_alloc-keep-track-of-free-highatomic.patch