1 files changed, 150 insertions, 130 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index ebaf79d683..4255619a1a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -411,10 +411,10 @@ static int reclaimer_offset(void)
 {
 	BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD !=
 			PGDEMOTE_DIRECT - PGDEMOTE_KSWAPD);
-	BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD !=
-			PGSCAN_DIRECT - PGSCAN_KSWAPD);
 	BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD !=
 			PGDEMOTE_KHUGEPAGED - PGDEMOTE_KSWAPD);
+	BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD !=
+			PGSCAN_DIRECT - PGSCAN_KSWAPD);
 	BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD !=
 			PGSCAN_KHUGEPAGED - PGSCAN_KSWAPD);
 
@@ -977,7 +977,8 @@ static unsigned int demote_folio_list(struct list_head *demote_folios,
 		      (unsigned long)&mtc, MIGRATE_ASYNC, MR_DEMOTION,
 		      &nr_succeeded);
 
-	__count_vm_events(PGDEMOTE_KSWAPD + reclaimer_offset(), nr_succeeded);
+	mod_node_page_state(pgdat, PGDEMOTE_KSWAPD + reclaimer_offset(),
+			    nr_succeeded);
 
 	return nr_succeeded;
 }
@@ -2222,7 +2223,7 @@ static void prepare_scan_control(pg_data_t *pgdat, struct scan_control *sc)
 	 * Flush the memory cgroup stats, so that we read accurate per-memcg
 	 * lruvec stats for heuristics.
 	 */
-	mem_cgroup_flush_stats();
+	mem_cgroup_flush_stats(sc->target_mem_cgroup);
 
 	/*
 	 * Determine the scan balance between anon and file LRUs.
@@ -2667,13 +2668,14 @@ static void get_item_key(void *item, int *key)
 	key[1] = hash >> BLOOM_FILTER_SHIFT;
 }
 
-static bool test_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item)
+static bool test_bloom_filter(struct lru_gen_mm_state *mm_state, unsigned long seq,
+			      void *item)
 {
 	int key[2];
 	unsigned long *filter;
 	int gen = filter_gen_from_seq(seq);
 
-	filter = READ_ONCE(lruvec->mm_state.filters[gen]);
+	filter = READ_ONCE(mm_state->filters[gen]);
 	if (!filter)
 		return true;
 
@@ -2682,13 +2684,14 @@ static bool test_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *it
 	return test_bit(key[0], filter) && test_bit(key[1], filter);
 }
 
-static void update_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item)
+static void update_bloom_filter(struct lru_gen_mm_state *mm_state, unsigned long seq,
+				void *item)
 {
 	int key[2];
 	unsigned long *filter;
 	int gen = filter_gen_from_seq(seq);
 
-	filter = READ_ONCE(lruvec->mm_state.filters[gen]);
+	filter = READ_ONCE(mm_state->filters[gen]);
 	if (!filter)
 		return;
 
@@ -2700,12 +2703,12 @@ static void update_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *
 		set_bit(key[1], filter);
 }
 
-static void reset_bloom_filter(struct lruvec *lruvec, unsigned long seq)
+static void reset_bloom_filter(struct lru_gen_mm_state *mm_state, unsigned long seq)
 {
 	unsigned long *filter;
 	int gen = filter_gen_from_seq(seq);
 
-	filter = lruvec->mm_state.filters[gen];
+	filter = mm_state->filters[gen];
 	if (filter) {
 		bitmap_clear(filter, 0, BIT(BLOOM_FILTER_SHIFT));
 		return;
@@ -2713,13 +2716,15 @@ static void reset_bloom_filter(struct lruvec *lruvec, unsigned long seq)
 
 	filter = bitmap_zalloc(BIT(BLOOM_FILTER_SHIFT),
 			       __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN);
-	WRITE_ONCE(lruvec->mm_state.filters[gen], filter);
+	WRITE_ONCE(mm_state->filters[gen], filter);
 }
 
 /******************************************************************************
  *                          mm_struct list
  ******************************************************************************/
 
+#ifdef CONFIG_LRU_GEN_WALKS_MMU
+
 static struct lru_gen_mm_list *get_mm_list(struct mem_cgroup *memcg)
 {
 	static struct lru_gen_mm_list mm_list = {
@@ -2736,6 +2741,29 @@ static struct lru_gen_mm_list *get_mm_list(struct mem_cgroup *memcg)
 	return &mm_list;
 }
 
+static struct lru_gen_mm_state *get_mm_state(struct lruvec *lruvec)
+{
+	return &lruvec->mm_state;
+}
+
+static struct mm_struct *get_next_mm(struct lru_gen_mm_walk *walk)
+{
+	int key;
+	struct mm_struct *mm;
+	struct pglist_data *pgdat = lruvec_pgdat(walk->lruvec);
+	struct lru_gen_mm_state *mm_state = get_mm_state(walk->lruvec);
+
+	mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
+	key = pgdat->node_id % BITS_PER_TYPE(mm->lru_gen.bitmap);
+
+	if (!walk->force_scan && !test_bit(key, &mm->lru_gen.bitmap))
+		return NULL;
+
+	clear_bit(key, &mm->lru_gen.bitmap);
+
+	return mmget_not_zero(mm) ? mm : NULL;
+}
+
 void lru_gen_add_mm(struct mm_struct *mm)
 {
 	int nid;
@@ -2751,10 +2779,11 @@ void lru_gen_add_mm(struct mm_struct *mm)
 
 	for_each_node_state(nid, N_MEMORY) {
 		struct lruvec *lruvec = get_lruvec(memcg, nid);
+		struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 		/* the first addition since the last iteration */
-		if (lruvec->mm_state.tail == &mm_list->fifo)
-			lruvec->mm_state.tail = &mm->lru_gen.list;
+		if (mm_state->tail == &mm_list->fifo)
+			mm_state->tail = &mm->lru_gen.list;
 	}
 
 	list_add_tail(&mm->lru_gen.list, &mm_list->fifo);
@@ -2780,14 +2809,15 @@ void lru_gen_del_mm(struct mm_struct *mm)
 
 	for_each_node(nid) {
 		struct lruvec *lruvec = get_lruvec(memcg, nid);
+		struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 		/* where the current iteration continues after */
-		if (lruvec->mm_state.head == &mm->lru_gen.list)
-			lruvec->mm_state.head = lruvec->mm_state.head->prev;
+		if (mm_state->head == &mm->lru_gen.list)
+			mm_state->head = mm_state->head->prev;
 
 		/* where the last iteration ended before */
-		if (lruvec->mm_state.tail == &mm->lru_gen.list)
-			lruvec->mm_state.tail = lruvec->mm_state.tail->next;
+		if (mm_state->tail == &mm->lru_gen.list)
+			mm_state->tail = mm_state->tail->next;
 	}
 
 	list_del_init(&mm->lru_gen.list);
@@ -2830,10 +2860,30 @@ void lru_gen_migrate_mm(struct mm_struct *mm)
 }
 #endif
 
+#else /* !CONFIG_LRU_GEN_WALKS_MMU */
+
+static struct lru_gen_mm_list *get_mm_list(struct mem_cgroup *memcg)
+{
+	return NULL;
+}
+
+static struct lru_gen_mm_state *get_mm_state(struct lruvec *lruvec)
+{
+	return NULL;
+}
+
+static struct mm_struct *get_next_mm(struct lru_gen_mm_walk *walk)
+{
+	return NULL;
+}
+
+#endif
+
 static void reset_mm_stats(struct lruvec *lruvec, struct lru_gen_mm_walk *walk, bool last)
 {
 	int i;
 	int hist;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	lockdep_assert_held(&get_mm_list(lruvec_memcg(lruvec))->lock);
 
@@ -2841,44 +2891,20 @@ static void reset_mm_stats(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
 		hist = lru_hist_from_seq(walk->max_seq);
 
 		for (i = 0; i < NR_MM_STATS; i++) {
-			WRITE_ONCE(lruvec->mm_state.stats[hist][i],
-				   lruvec->mm_state.stats[hist][i] + walk->mm_stats[i]);
+			WRITE_ONCE(mm_state->stats[hist][i],
+				   mm_state->stats[hist][i] + walk->mm_stats[i]);
 			walk->mm_stats[i] = 0;
 		}
 	}
 
 	if (NR_HIST_GENS > 1 && last) {
-		hist = lru_hist_from_seq(lruvec->mm_state.seq + 1);
+		hist = lru_hist_from_seq(mm_state->seq + 1);
 
 		for (i = 0; i < NR_MM_STATS; i++)
-			WRITE_ONCE(lruvec->mm_state.stats[hist][i], 0);
+			WRITE_ONCE(mm_state->stats[hist][i], 0);
 	}
 }
 
-static bool should_skip_mm(struct mm_struct *mm, struct lru_gen_mm_walk *walk)
-{
-	int type;
-	unsigned long size = 0;
-	struct pglist_data *pgdat = lruvec_pgdat(walk->lruvec);
-	int key = pgdat->node_id % BITS_PER_TYPE(mm->lru_gen.bitmap);
-
-	if (!walk->force_scan && !test_bit(key, &mm->lru_gen.bitmap))
-		return true;
-
-	clear_bit(key, &mm->lru_gen.bitmap);
-
-	for (type = !walk->can_swap; type < ANON_AND_FILE; type++) {
-		size += type ? get_mm_counter(mm, MM_FILEPAGES) :
-			       get_mm_counter(mm, MM_ANONPAGES) +
-			       get_mm_counter(mm, MM_SHMEMPAGES);
-	}
-
-	if (size < MIN_LRU_BATCH)
-		return true;
-
-	return !mmget_not_zero(mm);
-}
-
 static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
 			    struct mm_struct **iter)
 {
@@ -2887,7 +2913,7 @@ static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
 	struct mm_struct *mm = NULL;
 	struct mem_cgroup *memcg = lruvec_memcg(lruvec);
 	struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
-	struct lru_gen_mm_state *mm_state = &lruvec->mm_state;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	/*
 	 * mm_state->seq is incremented after each iteration of mm_list. There
@@ -2925,11 +2951,7 @@ static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
 			mm_state->tail = mm_state->head->next;
 			walk->force_scan = true;
 		}
-
-		mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
-		if (should_skip_mm(mm, walk))
-			mm = NULL;
-	} while (!mm);
+	} while (!(mm = get_next_mm(walk)));
 done:
 	if (*iter || last)
 		reset_mm_stats(lruvec, walk, last);
@@ -2937,7 +2959,7 @@ done:
 	spin_unlock(&mm_list->lock);
 
 	if (mm && first)
-		reset_bloom_filter(lruvec, walk->max_seq + 1);
+		reset_bloom_filter(mm_state, walk->max_seq + 1);
 
 	if (*iter)
 		mmput_async(*iter);
@@ -2952,7 +2974,7 @@ static bool iterate_mm_list_nowalk(struct lruvec *lruvec, unsigned long max_seq)
 	bool success = false;
 	struct mem_cgroup *memcg = lruvec_memcg(lruvec);
 	struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
-	struct lru_gen_mm_state *mm_state = &lruvec->mm_state;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	spin_lock(&mm_list->lock);
 
@@ -3248,7 +3270,6 @@ static unsigned long get_pte_pfn(pte_t pte, struct vm_area_struct *vma, unsigned
 	return pfn;
 }
 
-#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
 static unsigned long get_pmd_pfn(pmd_t pmd, struct vm_area_struct *vma, unsigned long addr)
 {
 	unsigned long pfn = pmd_pfn(pmd);
@@ -3266,7 +3287,6 @@ static unsigned long get_pmd_pfn(pmd_t pmd, struct vm_area_struct *vma, unsigned
 
 	return pfn;
 }
-#endif
 
 static struct folio *get_pfn_folio(unsigned long pfn, struct mem_cgroup *memcg,
 				   struct pglist_data *pgdat, bool can_swap)
@@ -3369,7 +3389,6 @@ restart:
 	return suitable_to_scan(total, young);
 }
 
-#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
 static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area_struct *vma,
 				  struct mm_walk *args, unsigned long *bitmap, unsigned long *first)
 {
@@ -3447,12 +3466,6 @@ next:
 done:
 	*first = -1;
 }
-#else
-static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area_struct *vma,
-				  struct mm_walk *args, unsigned long *bitmap, unsigned long *first)
-{
-}
-#endif
 
 static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
 			   struct mm_walk *args)
@@ -3465,6 +3478,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
 	DECLARE_BITMAP(bitmap, MIN_LRU_BATCH);
 	unsigned long first = -1;
 	struct lru_gen_mm_walk *walk = args->private;
+	struct lru_gen_mm_state *mm_state = get_mm_state(walk->lruvec);
 
 	VM_WARN_ON_ONCE(pud_leaf(*pud));
 
@@ -3487,7 +3501,6 @@ restart:
 			continue;
 		}
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 		if (pmd_trans_huge(val)) {
 			unsigned long pfn = pmd_pfn(val);
 			struct pglist_data *pgdat = lruvec_pgdat(walk->lruvec);
@@ -3506,7 +3519,7 @@ restart:
 			walk_pmd_range_locked(pud, addr, vma, args, bitmap, &first);
 			continue;
 		}
-#endif
+
 		walk->mm_stats[MM_NONLEAF_TOTAL]++;
 
 		if (should_clear_pmd_young()) {
@@ -3516,7 +3529,7 @@ restart:
 			walk_pmd_range_locked(pud, addr, vma, args, bitmap, &first);
 		}
 
-		if (!walk->force_scan && !test_bloom_filter(walk->lruvec, walk->max_seq, pmd + i))
+		if (!walk->force_scan && !test_bloom_filter(mm_state, walk->max_seq, pmd + i))
 			continue;
 
 		walk->mm_stats[MM_NONLEAF_FOUND]++;
@@ -3527,7 +3540,7 @@ restart:
 		walk->mm_stats[MM_NONLEAF_ADDED]++;
 
 		/* carry over to the next generation */
-		update_bloom_filter(walk->lruvec, walk->max_seq + 1, pmd + i);
+		update_bloom_filter(mm_state, walk->max_seq + 1, pmd + i);
 	}
 
 	walk_pmd_range_locked(pud, -1, vma, args, bitmap, &first);
@@ -3734,16 +3747,25 @@ next:
 	return success;
 }
 
-static void inc_max_seq(struct lruvec *lruvec, bool can_swap, bool force_scan)
+static bool inc_max_seq(struct lruvec *lruvec, unsigned long max_seq,
+			bool can_swap, bool force_scan)
 {
+	bool success;
 	int prev, next;
 	int type, zone;
 	struct lru_gen_folio *lrugen = &lruvec->lrugen;
 restart:
+	if (max_seq < READ_ONCE(lrugen->max_seq))
+		return false;
+
 	spin_lock_irq(&lruvec->lru_lock);
 
 	VM_WARN_ON_ONCE(!seq_is_valid(lruvec));
 
+	success = max_seq == lrugen->max_seq;
+	if (!success)
+		goto unlock;
+
 	for (type = ANON_AND_FILE - 1; type >= 0; type--) {
 		if (get_nr_gens(lruvec, type) != MAX_NR_GENS)
 			continue;
@@ -3787,8 +3809,10 @@ restart:
 	WRITE_ONCE(lrugen->timestamps[next], jiffies);
 	/* make sure preceding modifications appear */
 	smp_store_release(&lrugen->max_seq, lrugen->max_seq + 1);
-
+unlock:
 	spin_unlock_irq(&lruvec->lru_lock);
+
+	return success;
 }
 
 static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq,
@@ -3798,14 +3822,16 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq,
 	struct lru_gen_mm_walk *walk;
 	struct mm_struct *mm = NULL;
 	struct lru_gen_folio *lrugen = &lruvec->lrugen;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	VM_WARN_ON_ONCE(max_seq > READ_ONCE(lrugen->max_seq));
 
+	if (!mm_state)
+		return inc_max_seq(lruvec, max_seq, can_swap, force_scan);
+
 	/* see the comment in iterate_mm_list() */
-	if (max_seq <= READ_ONCE(lruvec->mm_state.seq)) {
-		success = false;
-		goto done;
-	}
+	if (max_seq <= READ_ONCE(mm_state->seq))
+		return false;
 
 	/*
 	 * If the hardware doesn't automatically set the accessed bit, fallback
@@ -3835,8 +3861,10 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq,
 			walk_mm(lruvec, mm, walk);
 	} while (mm);
 done:
-	if (success)
-		inc_max_seq(lruvec, can_swap, force_scan);
+	if (success) {
+		success = inc_max_seq(lruvec, max_seq, can_swap, force_scan);
+		WARN_ON_ONCE(!success);
+	}
 
 	return success;
 }
@@ -3961,6 +3989,7 @@ void lru_gen_look_around(struct page_vma_mapped_walk *pvmw)
 	struct mem_cgroup *memcg = folio_memcg(folio);
 	struct pglist_data *pgdat = folio_pgdat(folio);
 	struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat);
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 	DEFINE_MAX_SEQ(lruvec);
 	int old_gen, new_gen = lru_gen_from_seq(max_seq);
 
@@ -4043,8 +4072,8 @@ void lru_gen_look_around(struct page_vma_mapped_walk *pvmw)
 	mem_cgroup_unlock_pages();
 
 	/* feedback from rmap walkers to page table walkers */
-	if (suitable_to_scan(i, young))
-		update_bloom_filter(lruvec, max_seq, pvmw->pmd);
+	if (mm_state && suitable_to_scan(i, young))
+		update_bloom_filter(mm_state, max_seq, pvmw->pmd);
 }
 
 /******************************************************************************
@@ -4060,13 +4089,6 @@ enum {
 	MEMCG_LRU_YOUNG,
 };
 
-#ifdef CONFIG_MEMCG
-
-static int lru_gen_memcg_seg(struct lruvec *lruvec)
-{
-	return READ_ONCE(lruvec->lrugen.seg);
-}
-
 static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op)
 {
 	int seg;
@@ -4113,6 +4135,8 @@ static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op)
 	spin_unlock_irqrestore(&pgdat->memcg_lru.lock, flags);
 }
 
+#ifdef CONFIG_MEMCG
+
 void lru_gen_online_memcg(struct mem_cgroup *memcg)
 {
 	int gen;
@@ -4180,18 +4204,11 @@ void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid)
 	struct lruvec *lruvec = get_lruvec(memcg, nid);
 
 	/* see the comment on MEMCG_NR_GENS */
-	if (lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD)
+	if (READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_HEAD)
 		lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD);
 }
 
-#else /* !CONFIG_MEMCG */
-
-static int lru_gen_memcg_seg(struct lruvec *lruvec)
-{
-	return 0;
-}
-
-#endif
+#endif /* CONFIG_MEMCG */
 
 /******************************************************************************
  *                          the eviction
@@ -4739,7 +4756,7 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc)
 
 	if (mem_cgroup_below_low(NULL, memcg)) {
 		/* see the comment on MEMCG_NR_GENS */
-		if (lru_gen_memcg_seg(lruvec) != MEMCG_LRU_TAIL)
+		if (READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_TAIL)
 			return MEMCG_LRU_TAIL;
 
 		memcg_memory_event(memcg, MEMCG_LOW);
@@ -4762,12 +4779,10 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc)
 		return 0;
 
 	/* one retry if offlined or too small */
-	return lru_gen_memcg_seg(lruvec) != MEMCG_LRU_TAIL ?
+	return READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_TAIL ?
 	       MEMCG_LRU_TAIL : MEMCG_LRU_YOUNG;
 }
 
-#ifdef CONFIG_MEMCG
-
 static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc)
 {
 	int op;
@@ -4859,20 +4874,6 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc
 	blk_finish_plug(&plug);
 }
 
-#else /* !CONFIG_MEMCG */
-
-static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc)
-{
-	BUILD_BUG();
-}
-
-static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
-{
-	BUILD_BUG();
-}
-
-#endif
-
 static void set_initial_priority(struct pglist_data *pgdat, struct scan_control *sc)
 {
 	int priority;
@@ -5220,6 +5221,7 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec,
 	int type, tier;
 	int hist = lru_hist_from_seq(seq);
 	struct lru_gen_folio *lrugen = &lruvec->lrugen;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	for (tier = 0; tier < MAX_NR_TIERS; tier++) {
 		seq_printf(m, "            %10d", tier);
@@ -5245,6 +5247,9 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec,
 		seq_putc(m, '\n');
 	}
 
+	if (!mm_state)
+		return;
+
 	seq_puts(m, "                      ");
 	for (i = 0; i < NR_MM_STATS; i++) {
 		const char *s = "      ";
@@ -5252,10 +5257,10 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec,
 
 		if (seq == max_seq && NR_HIST_GENS == 1) {
 			s = "LOYNFA";
-			n = READ_ONCE(lruvec->mm_state.stats[hist][i]);
+			n = READ_ONCE(mm_state->stats[hist][i]);
 		} else if (seq != max_seq && NR_HIST_GENS > 1) {
 			s = "loynfa";
-			n = READ_ONCE(lruvec->mm_state.stats[hist][i]);
+			n = READ_ONCE(mm_state->stats[hist][i]);
 		}
 
 		seq_printf(m, " %10lu%c", n, s[i]);
@@ -5519,11 +5524,24 @@ static const struct file_operations lru_gen_ro_fops = {
  *                          initialization
  ******************************************************************************/
 
+void lru_gen_init_pgdat(struct pglist_data *pgdat)
+{
+	int i, j;
+
+	spin_lock_init(&pgdat->memcg_lru.lock);
+
+	for (i = 0; i < MEMCG_NR_GENS; i++) {
+		for (j = 0; j < MEMCG_NR_BINS; j++)
+			INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i);
+	}
+}
+
 void lru_gen_init_lruvec(struct lruvec *lruvec)
 {
 	int i;
 	int gen, type, zone;
 	struct lru_gen_folio *lrugen = &lruvec->lrugen;
+	struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 	lrugen->max_seq = MIN_NR_GENS + 1;
 	lrugen->enabled = lru_gen_enabled();
@@ -5534,47 +5552,46 @@ void lru_gen_init_lruvec(struct lruvec *lruvec)
 	for_each_gen_type_zone(gen, type, zone)
 		INIT_LIST_HEAD(&lrugen->folios[gen][type][zone]);
 
-	lruvec->mm_state.seq = MIN_NR_GENS;
+	if (mm_state)
+		mm_state->seq = MIN_NR_GENS;
 }
 
 #ifdef CONFIG_MEMCG
 
-void lru_gen_init_pgdat(struct pglist_data *pgdat)
+void lru_gen_init_memcg(struct mem_cgroup *memcg)
 {
-	int i, j;
+	struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
 
-	spin_lock_init(&pgdat->memcg_lru.lock);
+	if (!mm_list)
+		return;
 
-	for (i = 0; i < MEMCG_NR_GENS; i++) {
-		for (j = 0; j < MEMCG_NR_BINS; j++)
-			INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i);
-	}
-}
-
-void lru_gen_init_memcg(struct mem_cgroup *memcg)
-{
-	INIT_LIST_HEAD(&memcg->mm_list.fifo);
-	spin_lock_init(&memcg->mm_list.lock);
+	INIT_LIST_HEAD(&mm_list->fifo);
+	spin_lock_init(&mm_list->lock);
 }
 
 void lru_gen_exit_memcg(struct mem_cgroup *memcg)
 {
 	int i;
 	int nid;
+	struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
 
-	VM_WARN_ON_ONCE(!list_empty(&memcg->mm_list.fifo));
+	VM_WARN_ON_ONCE(mm_list && !list_empty(&mm_list->fifo));
 
 	for_each_node(nid) {
 		struct lruvec *lruvec = get_lruvec(memcg, nid);
+		struct lru_gen_mm_state *mm_state = get_mm_state(lruvec);
 
 		VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0,
 					   sizeof(lruvec->lrugen.nr_pages)));
 
 		lruvec->lrugen.list.next = LIST_POISON1;
 
+		if (!mm_state)
+			continue;
+
 		for (i = 0; i < NR_BLOOM_FILTERS; i++) {
-			bitmap_free(lruvec->mm_state.filters[i]);
-			lruvec->mm_state.filters[i] = NULL;
+			bitmap_free(mm_state->filters[i]);
+			mm_state->filters[i] = NULL;
 		}
 	}
 }
@@ -5600,14 +5617,17 @@ late_initcall(init_lru_gen);
 
 static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc)
 {
+	BUILD_BUG();
 }
 
 static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
 {
+	BUILD_BUG();
 }
 
 static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc)
 {
+	BUILD_BUG();
 }
 
 #endif /* CONFIG_LRU_GEN */
@@ -6403,7 +6423,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
 	 * scan_control uses s8 fields for order, priority, and reclaim_idx.
 	 * Confirm they are large enough for max values.
 	 */
-	BUILD_BUG_ON(MAX_ORDER >= S8_MAX);
+	BUILD_BUG_ON(MAX_PAGE_ORDER >= S8_MAX);
 	BUILD_BUG_ON(DEF_PRIORITY > S8_MAX);
 	BUILD_BUG_ON(MAX_NR_ZONES > S8_MAX);