+ mm-memcontrol-avoid-duplicated-memcg-enable-check.patch added to mm-unstable branch

+ mm-memcontrol-avoid-duplicated-memcg-enable-check.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm, memcontrol: avoid duplicated memcg enable check
has been added to the -mm mm-unstable branch.  Its filename is
     mm-memcontrol-avoid-duplicated-memcg-enable-check.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcontrol-avoid-duplicated-memcg-enable-check.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@tencent.com>
Subject: mm, memcontrol: avoid duplicated memcg enable check
Date: Tue, 10 Dec 2024 17:28:03 +0800

Patch series "mm/swap_cgroup: remove global swap cgroup lock", v2.

This series removes the global swap cgroup lock.  The critical section of
this lock is very short but it's still a bottle neck for mass parallel
swap workloads.

Up to 10% performance gain for tmpfs build kernel test on a 48c96t system,
and no regression for other cases:

Testing using 64G brd and build with build kernel with make -j96 in 1.5G
memory cgroup using 4k folios showed below improvement (10 test run):

Before this series:
Sys time: 10809.46 (stdev 80.831491)
Real time: 171.41 (stdev 1.239894)

After this commit:
Sys time: 9621.26 (stdev 34.620000), -10.42%
Real time: 160.00 (stdev 0.497814), -6.57%

With 64k folios and 2G memcg:
Before this series:
Sys time: 8231.99 (stdev 30.030994)
Real time: 143.57 (stdev 0.577394)

After this commit:
Sys time: 7403.47 (stdev 6.270000), -10.06%
Real time: 135.18 (stdev 0.605000), -5.84%

Sequential swapout of 8G 64k zero folios (24 test run):
Before this series:
5461409.12 us (stdev 183957.827084)

After this commit:
5420447.26 us (stdev 196419.240317)

Sequential swapin of 8G 4k zero folios (24 test run):
Before this series:
19736958.916667 us (stdev 189027.246676)

After this commit:
19662182.629630 us (stdev 172717.640614)


This patch (of 3):

mem_cgroup_uncharge_swap() includes a mem_cgroup_disabled() check, so the
caller doesn't need to check that.

Link: https://lkml.kernel.org/r/20241210092805.87281-1-ryncsn@gmail.com
Link: https://lkml.kernel.org/r/20241210092805.87281-2-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/memcontrol.c~mm-memcontrol-avoid-duplicated-memcg-enable-check
+++ a/mm/memcontrol.c
@@ -4609,7 +4609,7 @@ void mem_cgroup_swapin_uncharge_swap(swp
 	 * correspond 1:1 to page and swap slot lifetimes: we charge the
 	 * page to memory here, and uncharge swap when the slot is freed.
 	 */
-	if (!mem_cgroup_disabled() && do_memsw_account()) {
+	if (do_memsw_account()) {
 		/*
 		 * The swap entry might not get freed for a long time,
 		 * let's not wait for it.  The page already received a
_

Patches currently in -mm which might be from kasong@tencent.com are

zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch
zram-fix-uninitialized-zram-not-releasing-backing-device.patch
mm-memcontrol-avoid-duplicated-memcg-enable-check.patch
mm-swap_cgroup-remove-swap_cgroup_cmpxchg.patch
mm-swap_cgroup-remove-global-swap-cgroup-lock.patch

+ mm-memcontrol-avoid-duplicated-memcg-enable-check.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm, memcontrol: avoid duplicated memcg enable check
has been added to the -mm mm-unstable branch.  Its filename is
     mm-memcontrol-avoid-duplicated-memcg-enable-check.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcontrol-avoid-duplicated-memcg-enable-check.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@tencent.com>
Subject: mm, memcontrol: avoid duplicated memcg enable check
Date: Wed, 18 Dec 2024 19:46:30 +0800

Patch series "mm/swap_cgroup: remove global swap cgroup lock", v3.

This series removes the global swap cgroup lock.  The critical section of
this lock is very short but it's still a bottle neck for mass parallel
swap workloads.

Up to 10% performance gain for tmpfs build kernel test on a 48c96t system
under memory pressure, and no regression for other cases:


This patch (of 3):

mem_cgroup_uncharge_swap() includes a mem_cgroup_disabled() check,
so the caller doesn't need to check that.

Link: https://lkml.kernel.org/r/20241218114633.85196-1-ryncsn@gmail.com
Link: https://lkml.kernel.org/r/20241218114633.85196-2-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/memcontrol.c~mm-memcontrol-avoid-duplicated-memcg-enable-check
+++ a/mm/memcontrol.c
@@ -4595,7 +4595,7 @@ void mem_cgroup_swapin_uncharge_swap(swp
 	 * correspond 1:1 to page and swap slot lifetimes: we charge the
 	 * page to memory here, and uncharge swap when the slot is freed.
 	 */
-	if (!mem_cgroup_disabled() && do_memsw_account()) {
+	if (do_memsw_account()) {
 		/*
 		 * The swap entry might not get freed for a long time,
 		 * let's not wait for it.  The page already received a
_

Patches currently in -mm which might be from kasong@tencent.com are

zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch
zram-fix-uninitialized-zram-not-releasing-backing-device.patch
mm-memcontrol-avoid-duplicated-memcg-enable-check.patch
mm-swap_cgroup-remove-swap_cgroup_cmpxchg.patch
mm-swap_cgroup-remove-global-swap-cgroup-lock.patch
mm-swap_cgroup-decouple-swap-cgroup-recording-and-clearing.patch