From bc2ff4cbc3294c01f29449405c42ee26ee0e1f59 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 27 Feb 2024 17:42:45 +0000 Subject: [PATCH] mm: free folios in a batch in shrink_folio_list() Use free_unref_page_batch() to free the folios. This may increase the number of IPIs from calling try_to_unmap_flush() more often, but that's going to be very workload-dependent. It may even reduce the number of IPIs as we now batch-free large folios instead of freeing them one at a time. Link: https://lkml.kernel.org/r/20240227174254.710559-12-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: David Hildenbrand Cc: Ryan Roberts Signed-off-by: Andrew Morton --- mm/vmscan.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index dcfbe617e9ef..144879d5bb89 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1006,14 +1006,15 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, struct pglist_data *pgdat, struct scan_control *sc, struct reclaim_stat *stat, bool ignore_references) { + struct folio_batch free_folios; LIST_HEAD(ret_folios); - LIST_HEAD(free_folios); LIST_HEAD(demote_folios); unsigned int nr_reclaimed = 0; unsigned int pgactivate = 0; bool do_demote_pass; struct swap_iocb *plug = NULL; + folio_batch_init(&free_folios); memset(stat, 0, sizeof(*stat)); cond_resched(); do_demote_pass = can_demote(pgdat->node_id, sc); @@ -1412,14 +1413,11 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, */ nr_reclaimed += nr_pages; - /* - * Is there need to periodically free_folio_list? It would - * appear not as the counts should be low - */ - if (unlikely(folio_test_large(folio))) - destroy_large_folio(folio); - else - list_add(&folio->lru, &free_folios); + if (folio_batch_add(&free_folios, folio) == 0) { + mem_cgroup_uncharge_folios(&free_folios); + try_to_unmap_flush(); + free_unref_folios(&free_folios); + } continue; activate_locked_split: @@ -1483,9 +1481,9 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, pgactivate = stat->nr_activate[0] + stat->nr_activate[1]; - mem_cgroup_uncharge_list(&free_folios); + mem_cgroup_uncharge_folios(&free_folios); try_to_unmap_flush(); - free_unref_page_list(&free_folios); + free_unref_folios(&free_folios); list_splice(&ret_folios, folio_list); count_vm_events(PGACTIVATE, pgactivate);