Start converting the LRU from pagevecs to folio_batches.
Combine the functionality of pagevec_add_and_need_flush() with
pagevec_lru_move_fn() in the new folio_batch_add_and_move().
Convert the lru_rotate pagevec to a folio_batch.
Adds 223 bytes total to kernel text, because we're duplicating
infrastructure. This will be more than made up for in future patches.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
mm/swap.c | 78 +++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 56 insertions(+), 22 deletions(-)
diff --git a/mm/swap.c b/mm/swap.c
index 275a4ea1bc66..a983a1b93e73 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -46,10 +46,10 @@
/* How many pages do we try to swap or page in/out together? */
int page_cluster;
-/* Protecting only lru_rotate.pvec which requires disabling interrupts */
+/* Protecting only lru_rotate.fbatch which requires disabling interrupts */
struct lru_rotate {
local_lock_t lock;
- struct pagevec pvec;
+ struct folio_batch fbatch;
};
static DEFINE_PER_CPU(struct lru_rotate, lru_rotate) = {
.lock = INIT_LOCAL_LOCK(lock),
@@ -214,18 +214,6 @@ static void pagevec_lru_move_fn(struct pagevec *pvec,
pagevec_reinit(pvec);
}
-static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec)
-{
- struct folio *folio = page_folio(page);
-
- if (!folio_test_unevictable(folio)) {
- lruvec_del_folio(lruvec, folio);
- folio_clear_active(folio);
- lruvec_add_folio_tail(lruvec, folio);
- __count_vm_events(PGROTATED, folio_nr_pages(folio));
- }
-}
-
/* return true if pagevec needs to drain */
static bool pagevec_add_and_need_flush(struct pagevec *pvec, struct page *page)
{
@@ -238,6 +226,52 @@ static bool pagevec_add_and_need_flush(struct pagevec *pvec, struct page *page)
return ret;
}
+typedef void (*move_fn_t)(struct lruvec *lruvec, struct folio *folio);
+
+static void folio_batch_move_lru(struct folio_batch *fbatch, move_fn_t move_fn)
+{
+ int i;
+ struct lruvec *lruvec = NULL;
+ unsigned long flags = 0;
+
+ for (i = 0; i < folio_batch_count(fbatch); i++) {
+ struct folio *folio = fbatch->folios[i];
+
+ /* block memcg migration while the folio moves between lru */
+ if (!folio_test_clear_lru(folio))
+ continue;
+
+ lruvec = folio_lruvec_relock_irqsave(folio, lruvec, &flags);
+ move_fn(lruvec, folio);
+
+ folio_set_lru(folio);
+ }
+
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ folios_put(fbatch->folios, folio_batch_count(fbatch));
+ folio_batch_init(fbatch);
+}
+
+static void folio_batch_add_and_move(struct folio_batch *fbatch,
+ struct folio *folio, move_fn_t move_fn)
+{
+ if (folio_batch_add(fbatch, folio) && !folio_test_large(folio) &&
+ !lru_cache_disabled())
+ return;
+ folio_batch_move_lru(fbatch, move_fn);
+}
+
+static void lru_move_tail_fn(struct lruvec *lruvec, struct folio *folio)
+{
+ if (!folio_test_unevictable(folio)) {
+ lruvec_del_folio(lruvec, folio);
+ folio_clear_active(folio);
+ lruvec_add_folio_tail(lruvec, folio);
+ __count_vm_events(PGROTATED, folio_nr_pages(folio));
+ }
+}
+
/*
* Writeback is about to end against a folio which has been marked for
* immediate reclaim. If it still appears to be reclaimable, move it
@@ -249,14 +283,13 @@ void folio_rotate_reclaimable(struct folio *folio)
{
if (!folio_test_locked(folio) && !folio_test_dirty(folio) &&
!folio_test_unevictable(folio) && folio_test_lru(folio)) {
- struct pagevec *pvec;
+ struct folio_batch *fbatch;
unsigned long flags;
folio_get(folio);
local_lock_irqsave(&lru_rotate.lock, flags);
- pvec = this_cpu_ptr(&lru_rotate.pvec);
- if (pagevec_add_and_need_flush(pvec, &folio->page))
- pagevec_lru_move_fn(pvec, pagevec_move_tail_fn);
+ fbatch = this_cpu_ptr(&lru_rotate.fbatch);
+ folio_batch_add_and_move(fbatch, folio, lru_move_tail_fn);
local_unlock_irqrestore(&lru_rotate.lock, flags);
}
}
@@ -595,19 +628,20 @@ static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec)
*/
void lru_add_drain_cpu(int cpu)
{
+ struct folio_batch *fbatch;
struct pagevec *pvec = &per_cpu(lru_pvecs.lru_add, cpu);
if (pagevec_count(pvec))
__pagevec_lru_add(pvec);
- pvec = &per_cpu(lru_rotate.pvec, cpu);
+ fbatch = &per_cpu(lru_rotate.fbatch, cpu);
/* Disabling interrupts below acts as a compiler barrier. */
- if (data_race(pagevec_count(pvec))) {
+ if (data_race(folio_batch_count(fbatch))) {
unsigned long flags;
/* No harm done if a racing interrupt already did this */
local_lock_irqsave(&lru_rotate.lock, flags);
- pagevec_lru_move_fn(pvec, pagevec_move_tail_fn);
+ folio_batch_move_lru(fbatch, lru_move_tail_fn);
local_unlock_irqrestore(&lru_rotate.lock, flags);
}
@@ -824,7 +858,7 @@ static inline void __lru_add_drain_all(bool force_all_cpus)
struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
if (pagevec_count(&per_cpu(lru_pvecs.lru_add, cpu)) ||
- data_race(pagevec_count(&per_cpu(lru_rotate.pvec, cpu))) ||
+ data_race(folio_batch_count(&per_cpu(lru_rotate.fbatch, cpu))) ||
pagevec_count(&per_cpu(lru_pvecs.lru_deactivate_file, cpu)) ||
pagevec_count(&per_cpu(lru_pvecs.lru_deactivate, cpu)) ||
pagevec_count(&per_cpu(lru_pvecs.lru_lazyfree, cpu)) ||
--
2.35.1
