[PATCH 7/7] mm: Use free_unref_folios() in put_pages_list()

From: Matthew Wilcox (Oracle)
Date: Mon Aug 21 2023 - 16:45:05 EST


Break up the list of folios into batches here so that the
folios are more likely to be cache hot when doing the
rest of the processing.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
mm/swap.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/mm/swap.c b/mm/swap.c
index 8ebb10d44de7..51a613f477a9 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -138,22 +138,26 @@ EXPORT_SYMBOL(__folio_put);
*/
void put_pages_list(struct list_head *pages)
{
- struct folio *folio, *next;
+ struct folio_batch fbatch;
+ struct folio *folio;

- list_for_each_entry_safe(folio, next, pages, lru) {
- if (!folio_put_testzero(folio)) {
- list_del(&folio->lru);
+ folio_batch_init(&fbatch);
+ list_for_each_entry(folio, pages, lru) {
+ if (!folio_put_testzero(folio))
continue;
- }
if (folio_test_large(folio)) {
- list_del(&folio->lru);
__folio_put_large(folio);
continue;
}
/* LRU flag must be clear because it's passed using the lru */
+ if (folio_batch_add(&fbatch, folio) > 0)
+ continue;
+ free_unref_folios(&fbatch);
+ fbatch.nr = 0;
}

- free_unref_page_list(pages);
+ if (fbatch.nr)
+ free_unref_folios(&fbatch);
INIT_LIST_HEAD(pages);
}
EXPORT_SYMBOL(put_pages_list);
--
2.40.1