@@ -330,7 +330,7 @@ struct mem_cgroup {
struct deferred_split deferred_split_queue;
#endif
-#ifdef CONFIG_LRU_GEN
+#ifdef CONFIG_LRU_GEN_WALKS_MMU
/* per-memcg mm_struct list */
struct lru_gen_mm_list mm_list;
#endif
@@ -958,7 +958,7 @@ struct mm_struct {
*/
unsigned long ksm_zero_pages;
#endif /* CONFIG_KSM */
-#ifdef CONFIG_LRU_GEN
+#ifdef CONFIG_LRU_GEN_WALKS_MMU
struct {
/* this mm_struct is on lru_gen_mm_list */
struct list_head list;
@@ -973,7 +973,7 @@ struct mm_struct {
struct mem_cgroup *memcg;
#endif
} lru_gen;
-#endif /* CONFIG_LRU_GEN */
+#endif /* CONFIG_LRU_GEN_WALKS_MMU */
} __randomize_layout;
/*
@@ -1011,6 +1011,10 @@ struct lru_gen_mm_list {
spinlock_t lock;
};
+#endif /* CONFIG_LRU_GEN */
+
+#ifdef CONFIG_LRU_GEN_WALKS_MMU
+
void lru_gen_add_mm(struct mm_struct *mm);
void lru_gen_del_mm(struct mm_struct *mm);
#ifdef CONFIG_MEMCG
@@ -1036,7 +1040,7 @@ static inline void lru_gen_use_mm(struct mm_struct *mm)
WRITE_ONCE(mm->lru_gen.bitmap, -1);
}
-#else /* !CONFIG_LRU_GEN */
+#else /* !CONFIG_LRU_GEN_WALKS_MMU */
static inline void lru_gen_add_mm(struct mm_struct *mm)
{
@@ -1060,7 +1064,7 @@ static inline void lru_gen_use_mm(struct mm_struct *mm)
{
}
-#endif /* CONFIG_LRU_GEN */
+#endif /* CONFIG_LRU_GEN_WALKS_MMU */
struct vma_iterator {
struct ma_state mas;
@@ -640,9 +640,11 @@ struct lruvec {
#ifdef CONFIG_LRU_GEN
/* evictable pages divided into generations */
struct lru_gen_folio lrugen;
+#ifdef CONFIG_LRU_GEN_WALKS_MMU
/* to concurrently iterate lru_gen_mm_list */
struct lru_gen_mm_state mm_state;
#endif
+#endif /* CONFIG_LRU_GEN */
#ifdef CONFIG_MEMCG
struct pglist_data *pgdat;
#endif
@@ -2946,7 +2946,7 @@ pid_t kernel_clone(struct kernel_clone_args *args)
get_task_struct(p);
}
- if (IS_ENABLED(CONFIG_LRU_GEN) && !(clone_flags & CLONE_VM)) {
+ if (IS_ENABLED(CONFIG_LRU_GEN_WALKS_MMU) && !(clone_flags & CLONE_VM)) {
/* lock the task to synchronize with memcg migration */
task_lock(p);
lru_gen_add_mm(p->mm);
@@ -1274,6 +1274,10 @@ config LRU_GEN_STATS
from evicted generations for debugging purpose.
This option has a per-memcg and per-node memory overhead.
+
+config LRU_GEN_WALKS_MMU
+ def_bool y
+ depends on LRU_GEN && ARCH_HAS_HW_PTE_YOUNG
# }
config ARCH_SUPPORTS_PER_VMA_LOCK
@@ -2671,13 +2671,14 @@ 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;
@@ -2686,13 +2687,14 @@ 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;
@@ -2704,12 +2706,12 @@ 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;
@@ -2717,13 +2719,15 @@ 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 = {
@@ -2740,6 +2744,29 @@ 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;
@@ -2755,10 +2782,11 @@ 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);
@@ -2784,14 +2812,15 @@ 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);
@@ -2834,10 +2863,30 @@ 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);
@@ -2845,44 +2894,20 @@ 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)
{
@@ -2891,7 +2916,7 @@ 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
@@ -2929,11 +2954,7 @@ 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);
@@ -2941,7 +2962,7 @@ static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
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);
@@ -2956,7 +2977,7 @@ 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);
@@ -3469,6 +3490,7 @@ 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));
@@ -3520,7 +3542,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
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]++;
@@ -3531,7 +3553,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
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);
@@ -3738,16 +3760,25 @@ static bool try_to_inc_min_seq(struct lruvec *lruvec, bool can_swap)
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;
@@ -3791,8 +3822,10 @@ static void inc_max_seq(struct lruvec *lruvec, bool can_swap, bool force_scan)
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,
@@ -3802,14 +3835,16 @@ 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
@@ -3839,8 +3874,10 @@ 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;
}
@@ -3964,6 +4001,7 @@ 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);
@@ -4042,8 +4080,8 @@ 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);
}
/******************************************************************************
@@ -5219,6 +5257,7 @@ 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);
@@ -5244,6 +5283,9 @@ 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 = " ";
@@ -5251,10 +5293,10 @@ 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]);
@@ -5523,6 +5565,7 @@ 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();
@@ -5533,7 +5576,8 @@ 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
@@ -5552,28 +5596,38 @@ void lru_gen_init_pgdat(struct pglist_data *pgdat)
void lru_gen_init_memcg(struct mem_cgroup *memcg)
{
- INIT_LIST_HEAD(&memcg->mm_list.fifo);
- spin_lock_init(&memcg->mm_list.lock);
+ struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
+
+ if (!mm_list)
+ return;
+
+ 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;
}
}
}