[PATCH v2 00/26] mm/fbatch: drain lru_add_drain() and _all() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 01/26] mm/fbatch: remove !CONFIG_SMP special case of folio_activate() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 02/26] mm/fbatch: allow folios_put_refs() to skip xa_is_value() entries · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 03/26] mm/fbatch: temporarily disable lazyfree and mlock+munlock batching · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 04/26] mm/fbatch: lru bit set, no extra ref, while folio on per-cpu fbatch · Hugh Dickins <hughd@google.com> · 2026-09-09
Re: [PATCH v2 04/26] mm/fbatch: lru bit set, no extra ref, while folio on per-cpu fbatch · "Vlastimil Babka (SUSE)" <vbabka@kernel.org> · 2026-09-09
[PATCH v2 05/26] mm/fbatch: lru_add_del_folio()+folio_add_lru() after clear_lru() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 06/26] mm/fbatch: fbatch_drain_lazyfree(onstack fbatch) before ptl unlock · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 07/26] mm/fbatch: LRU_NEXT_ACTIVATE bit to optimize folio_activate() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 08/26] mm/fbatch: replace mlock_new_folio() by __folio_add_lru(,mlockit) · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 09/26] mm/fbatch: restore mlock+munlock batching, without extra ref · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 10/26] mm/fbatch: remove several uses of mlock_drain_local() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 11/26] mm/fbatch: remove migration's PAGE_WAS_MLOCKED lru_add_drain() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 12/26] mm/fbatch: remove percpu_pvec_drained and folios_put() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 13/26] mm/fbatch: no lru_add_drain to collect_longterm_unpinnable_folios() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 14/26] mm/fbatch: no lru_add_drain() nor _all() for memfd_wait_for_pins() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 15/26] mm/fbatch: remove shake_folio() shake_page() from memory-failure · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 16/26] mm/fbatch: remove lru_cache_disable() from NUMA folio migration · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 17/26] mm/fbatch: no lru_cache_disable() in __alloc_contig_migrate_range() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 18/26] mm/fbatch: remove lru_add_drain() and _all() calls from various · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 19/26] mm/fbatch: vm/stat_refresh include lru_add_drain() on each cpu · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 20/26] s390/fbatch: no lru_add_drain_all() in s390_wiggle_split_folio() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 21/26] block/fbatch: no lru_add_drain_all() in invalidate_bdev() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 22/26] fs/fbatch: drop_caches invalidate_bh_lrus() not lru_add_drain_all() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 23/26] fs,mm/fbatch: use invalidate_bh_lrus() not invalidate_bh_lrus_cpu() · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 24/26] fs,mm/fbatch: lru_cache_disable() keep off buffer_head lrus only · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 25/26] mm/fbatch: move lru_add_drain_all() declaration to mm/internal.h · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 26/26] mm/fbatch: drop reference inside the loop when draining · Hugh Dickins <hughd@google.com> · 2026-09-09
[PATCH v2 27/26] mm/fbatch: paranoid folio vmstats in folio_batch_move_lru() · Hugh Dickins <hughd@google.com> · 2026-09-09

HOTtoday

[PATCH v2 14/26] mm/fbatch: no lru_add_drain() nor _all() for memfd_wait_for_pins()

From: Hugh Dickins <hughd@google.com>
Date: 2026-09-09 10:10:25
Also in: linux-fsdevel, linux-mm, lkml
Subsystem: memory management, the rest, tmpfs (shmem filesystem) · Maintainers: Andrew Morton, Linus Torvalds, Hugh Dickins

memfd_tag_pins() used lru_add_drain(), memfd_wait_for_pins() then used
lru_add_drain_all(): remove those calls, no longer useful now that the
per-cpu fbatch references are gone.

Signed-off-by: Hugh Dickins <hughd@google.com>
---
 mm/memfd.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/mm/memfd.c b/mm/memfd.c
index c708d92533f4..064f24dcddaa 100644
--- a/mm/memfd.c
+++ b/mm/memfd.c

@@ -40,8 +40,6 @@ static void memfd_tag_pins(struct xa_state *xas)
 	struct folio *folio;
 	int latency = 0;
 
-	lru_add_drain();
-
 	xas_lock_irq(xas);
 	xas_for_each(xas, folio, ULONG_MAX) {
 		if (!xa_is_value(folio) && memfd_folio_has_extra_refs(folio))

@@ -168,9 +166,7 @@ static int memfd_wait_for_pins(struct address_space *mapping)
 		if (!xas_marked(&xas, MEMFD_TAG_PINNED))
 			break;
 
-		if (!scan)
-			lru_add_drain_all();
-		else if (schedule_timeout_killable((HZ << scan) / 200))
+		if (scan && schedule_timeout_killable((HZ << scan) / 200))
 			scan = LAST_SCAN;
 
 		xas_set(&xas, 0);

-- 
2.51.0