The patch titled
Subject: mm, swap: drop the flag TTRS_DIRECT
has been added to the -mm mm-unstable branch. Its filename is
mm-swap-drop-the-flag-ttrs_direct.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-drop-the-flag-ttrs_direct.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Kairui Song <kasong@xxxxxxxxxxx>
Subject: mm, swap: drop the flag TTRS_DIRECT
Date: Tue, 25 Feb 2025 02:02:07 +0800
This flag exists temporarily to allow the allocator to bypass the slot
cache during freeing, so reclaiming one slot will free the slot
immediately.
But now we have already removed slot cache usage on freeing, so this flag
has no effect now.
Link: https://lkml.kernel.org/r/20250224180212.22802-3-ryncsn@xxxxxxxxx
Signed-off-by: Kairui Song <kasong@xxxxxxxxxxx>
Reviewed-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Cc: Barry Song <v-songbaohua@xxxxxxxx>
Cc: Chris Li <chrisl@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Kalesh Singh <kaleshsingh@xxxxxxxxxx>
Cc: Matthew Wilcow (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Nhat Pham <nphamcs@xxxxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swapfile.c | 23 +++--------------------
1 file changed, 3 insertions(+), 20 deletions(-)
--- a/mm/swapfile.c~mm-swap-drop-the-flag-ttrs_direct
+++ a/mm/swapfile.c
@@ -158,8 +158,6 @@ static long swap_usage_in_pages(struct s
#define TTRS_UNMAPPED 0x2
/* Reclaim the swap entry if swap is getting full */
#define TTRS_FULL 0x4
-/* Reclaim directly, bypass the slot cache and don't touch device lock */
-#define TTRS_DIRECT 0x8
static bool swap_only_has_cache(struct swap_info_struct *si,
unsigned long offset, int nr_pages)
@@ -257,23 +255,8 @@ again:
if (!need_reclaim)
goto out_unlock;
- if (!(flags & TTRS_DIRECT)) {
- /* Free through slot cache */
- delete_from_swap_cache(folio);
- folio_set_dirty(folio);
- ret = nr_pages;
- goto out_unlock;
- }
-
- xa_lock_irq(&address_space->i_pages);
- __delete_from_swap_cache(folio, entry, NULL);
- xa_unlock_irq(&address_space->i_pages);
- folio_ref_sub(folio, nr_pages);
+ delete_from_swap_cache(folio);
folio_set_dirty(folio);
-
- ci = lock_cluster(si, offset);
- swap_entry_range_free(si, ci, entry, nr_pages);
- unlock_cluster(ci);
ret = nr_pages;
out_unlock:
folio_unlock(folio);
@@ -697,7 +680,7 @@ static bool cluster_reclaim_range(struct
offset++;
break;
case SWAP_HAS_CACHE:
- nr_reclaim = __try_to_reclaim_swap(si, offset, TTRS_ANYWAY | TTRS_DIRECT);
+ nr_reclaim = __try_to_reclaim_swap(si, offset, TTRS_ANYWAY);
if (nr_reclaim > 0)
offset += nr_reclaim;
else
@@ -849,7 +832,7 @@ static void swap_reclaim_full_clusters(s
if (READ_ONCE(map[offset]) == SWAP_HAS_CACHE) {
spin_unlock(&ci->lock);
nr_reclaim = __try_to_reclaim_swap(si, offset,
- TTRS_ANYWAY | TTRS_DIRECT);
+ TTRS_ANYWAY);
spin_lock(&ci->lock);
if (nr_reclaim) {
offset += abs(nr_reclaim);
_
Patches currently in -mm which might be from kasong@xxxxxxxxxxx are
mm-swap-avoid-reclaiming-irrelevant-swap-cache.patch
mm-swap-drop-the-flag-ttrs_direct.patch
mm-swap-avoid-redundant-swap-device-pinning.patch
mm-swap-dont-update-the-counter-up-front.patch
mm-swap-use-percpu-cluster-as-allocation-fast-path.patch
mm-swap-remove-swap-slot-cache.patch
mm-swap-simplify-folio-swap-allocation.patch
