From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8881F318EC7 for ; Fri, 31 Jul 2026 02:41:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785465705; cv=none; b=n9gMSTMfaso9fXC9LezxX5Z4wISKFz0JVCJPOupIgWryAeThWvzbCmg1yIszb2G+nSmTm/l5hAqKzMYdkxrUyevl/ooQH4iKDvHU2m61Ww2vYAcx/L/EdNEQtna1kwCnUztgqGZCcrJRafZqIOOZj+G1F+5+k5DRUvSTYrHAQn8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785465705; c=relaxed/simple; bh=ll0bUBKXBrBpO55hp9nlf21+m/zfoAm2i8qzT9eglPI=; h=Date:To:From:Subject:Message-Id; b=dxPQqJ4EAmaQhfM4gWS4pXBlilgaFyE5w6qMFOE8CYzm4zcRcZH0eEKSykOl6HpRyRXYT/GJhOPDCLw0Vg5s78KyyfVDOGzvhtM2Ra2Vkb9mhE6jrPQZd+ZbbMDRy20NV44alDvMUvry/XG2V8aBJnySiRRrNGkimn79LgjCygY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=RjLRS8Eo; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="RjLRS8Eo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 342001F00A3D; Fri, 31 Jul 2026 02:41:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1785465704; bh=HbRgxZrecMTVC+gFCFBQqZouAJPP9GTjARZIa9Wbg38=; h=Date:To:From:Subject; b=RjLRS8EoMzxLX8md+t0M1psBjBiAFjYwC+OOfAsDVjYaNJ9qjfO7zeiwfrPtw38o5 FJqt+FOkvAMdvECc/l6uNbBYf5WKtDkebmaMxAbZlm1Ev6dWGw6UM+H0ifMGH/PBdA aF4DWH6fAKuuDzsbMrcPxV0/SibHjMG49jfxcYV4= Date: Thu, 30 Jul 2026 19:41:43 -0700 To: mm-commits@vger.kernel.org,sj@kernel.org,shu17az@gmail.com,jiayuan.chen@shopee.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-damon-tests-core-kunit-test-split-above-max_nr_regions-2.patch removed from -mm tree Message-Id: <20260731024144.342001F00A3D@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/damon/tests/core-kunit: test split above max_nr_regions/2 has been removed from the -mm tree. Its filename was mm-damon-tests-core-kunit-test-split-above-max_nr_regions-2.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Jiayuan Chen Subject: mm/damon/tests/core-kunit: test split above max_nr_regions/2 Date: Mon, 29 Jun 2026 07:56:29 -0700 Add a test that exercises kdamond_split_regions() when the total region count is already above max_nr_regions / 2, asserting that the function still splits a fraction of the regions (makes progress) and does not overshoot max_nr_regions. The region size and min_region_sz are picked so the split arithmetic does not depend on the page size. All tests pass: damon: pass:31 fail:0 skip:0 total:31 Totals: pass:31 fail:0 skip:0 total:31 Link: https://lore.kernel.org/20260626085851.70754-3-jiayuan.chen@linux.dev Link: https://lore.kernel.org/20260629145630.134891-3-sj@kernel.org Signed-off-by: Jiayuan Chen Signed-off-by: SJ Park Reviewed-by: SJ Park Cc: Shu Anzai Signed-off-by: Andrew Morton --- mm/damon/tests/core-kunit.h | 64 ++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) --- a/mm/damon/tests/core-kunit.h~mm-damon-tests-core-kunit-test-split-above-max_nr_regions-2 +++ a/mm/damon/tests/core-kunit.h @@ -335,6 +335,69 @@ static void damon_test_split_regions_of( damon_destroy_ctx(c); } +/* + * When the total region count is already above max_nr_regions / 2, + * kdamond_split_regions() must keep refining the resolution by splitting a + * fraction of the regions (making progress), without exceeding + * max_nr_regions. + */ +static void damon_test_split_above_half_progresses(struct kunit *test) +{ + struct damon_ctx *c; + struct damon_target *t; + struct damon_region *r; + unsigned long start; + unsigned int nr_before, nr_after, i; + const unsigned int nr_init = 760; + const unsigned long region_sz = 100; + + c = damon_new_ctx(); + if (!c) + kunit_skip(test, "ctx alloc fail"); + + /* Keep the split arithmetic independent of the page size */ + c->min_region_sz = 1; + c->attrs.min_nr_regions = 10; + c->attrs.max_nr_regions = 1500; + + t = damon_new_target(); + if (!t) { + damon_destroy_ctx(c); + kunit_skip(test, "target alloc fail"); + } + + for (i = 0; i < nr_init; i++) { + start = i * region_sz; + r = damon_new_region(start, start + region_sz); + if (!r) { + damon_free_target(t); + damon_destroy_ctx(c); + kunit_skip(test, "region alloc fail"); + } + r->nr_accesses = (i & 1) ? 0 : 100; + r->age = 5; + damon_add_region(r, t); + } + + damon_add_target(c, t); + + nr_before = damon_nr_regions(t); + /* Above max_nr_regions / 2, so the blanket-split path is skipped */ + KUNIT_EXPECT_GT(test, (unsigned long)nr_before, + c->attrs.max_nr_regions / 2); + + kdamond_split_regions(c); + + nr_after = damon_nr_regions(t); + /* Still made progress ... */ + KUNIT_EXPECT_GT(test, nr_after, nr_before); + /* ... but did not overshoot the configured maximum */ + KUNIT_EXPECT_LE(test, (unsigned long)nr_after, + c->attrs.max_nr_regions); + + damon_destroy_ctx(c); +} + static void damon_test_ops_registration(struct kunit *test) { struct damon_ctx *c = damon_new_ctx(); @@ -1491,6 +1554,7 @@ static struct kunit_case damon_test_case KUNIT_CASE(damon_test_merge_two), KUNIT_CASE(damon_test_merge_regions_of), KUNIT_CASE(damon_test_split_regions_of), + KUNIT_CASE(damon_test_split_above_half_progresses), KUNIT_CASE(damon_test_ops_registration), KUNIT_CASE(damon_test_set_regions), KUNIT_CASE(damon_test_nr_accesses_to_accesses_bp), _ Patches currently in -mm which might be from jiayuan.chen@shopee.com are memcg-bail-out-memoryhigh-when-memcg-is-dying.patch memcg-bail-out-memorymax-when-memcg-is-dying.patch memcg-bail-out-proactive-reclaim-when-memcg-is-dying.patch memcg-v1-bail-out-reclaim-when-memcg-is-dying.patch