+ selftests-cgroup-use-runtime-page-size-for-zswpin-check.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

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The patch titled
     Subject: selftests/cgroup: use runtime page size for zswpin check
has been added to the -mm mm-new branch.  Its filename is
     selftests-cgroup-use-runtime-page-size-for-zswpin-check.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-cgroup-use-runtime-page-size-for-zswpin-check.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Li Wang <li.wang@linux.dev>
Subject: selftests/cgroup: use runtime page size for zswpin check
Date: Fri, 24 Apr 2026 12:00:54 +0800

test_zswapin compares memory.stat:zswpin (counted in pages) against a byte
threshold converted with PAGE_SIZE.  In cgroup selftests, PAGE_SIZE is
hardcoded to 4096, which makes the conversion wrong on systems with non-4K
base pages (e.g.  64K).

As a result, the test requires too many pages to pass and fails spuriously
even when zswap is working.

Use sysconf(_SC_PAGESIZE) for the zswpin threshold conversion so the check
matches the actual system page size.

Link: https://lore.kernel.org/20260424040059.12940-4-li.wang@linux.dev
Signed-off-by: Li Wang <li.wang@linux.dev>
Reviewed-by: Yosry Ahmed <yosry@kernel.org>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: Waiman Long <longman@redhat.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/cgroup/test_zswap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/testing/selftests/cgroup/test_zswap.c~selftests-cgroup-use-runtime-page-size-for-zswpin-check
+++ a/tools/testing/selftests/cgroup/test_zswap.c
@@ -245,7 +245,7 @@ static int test_zswapin(const char *root
 		goto out;
 	}
 
-	if (zswpin < MB(24) / PAGE_SIZE) {
+	if (zswpin < MB(24) / sysconf(_SC_PAGESIZE)) {
 		ksft_print_msg("at least 24MB should be brought back from zswap\n");
 		goto out;
 	}
_

Patches currently in -mm which might be from li.wang@linux.dev are

maintainers-update-li-wangs-email-address.patch
selftests-cgroup-skip-test_zswap-if-zswap-is-globally-disabled.patch
selftests-cgroup-avoid-oom-in-test_swapin_nozswap.patch
selftests-cgroup-use-runtime-page-size-for-zswpin-check.patch
selftests-cgroup-rename-page_size-to-buf_size-in-cgroup_util.patch
selftests-cgroup-replace-hardcoded-page-size-values-in-test_zswap.patch
selftest-cgroup-fix-zswap-test_no_invasive_cgroup_shrink-on-large-pagesize-system.patch
selftest-cgroup-fix-zswap-attempt_writeback-on-64k-pagesize-system.patch
selftests-cgroup-test_zswap-wait-for-asynchronous-writeback.patch