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 C2A874A2E1A; Wed, 29 Jul 2026 14:03:06 +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=1785333788; cv=none; b=mYm94jgP0oZHoouhmW11zrJXjSNjgiiOjqdhIvYm1yEAlXkUvoX36jHNsoZxwpkBiJyn4UOwarMxpTIuBIBLO0a4du9z32kXrRYHYV/NI4OYxc/DbCtoFwuFMmr1lnwHv/yt/2L0f0wvKG7VubXeKJtTrSo5E9ncJ8B4u9d+A1Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785333788; c=relaxed/simple; bh=LAOCZ6OX3C2XLdwJS4kLCYHcE8TRd595FwpreaVLtGE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I83yQj0wqoLb9NKWru5qGUhs5UJ62uiDugKnLhTY084fGCXfYPvYKbmJ5cOgWX9qc+n6xno+DIXRFuvVHE71v4QWZj9+Y+h6mh2/2UCh9OoynUVOGtBih/umpZYz7IyYBPHr/5bjfuVXKhuig0QRY/Im75Z51eBk5OlskRgztOo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WkYtsegm; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WkYtsegm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 659E61F00A3E; Wed, 29 Jul 2026 14:03:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785333786; bh=cKzzWsAXP/F08KNPNwIlHEjpZQDPuypTZix55EIf9Lc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WkYtsegmv9ZOWhUIMCf8RtEhUZVp6U+ch9Vjkaayub19BUjFZL4oN9K++Hbb1ovhu +QZtZEgerhSpv1IBGr7VZGTQhka/NPzaVH+IAgJ+eG23jPy477u7cyVJMDx8jlRe6r subUunDcT/sRdjKkZhsI4WF5VJoHENe/DCWmXpm7NLwAd+hUH8ArojaXMUxKP9xiER Tqpx6pLJRrZF7VGbzkKjD9w1i0xdyGoK6HoEyhy+uQNWZ4w5lzUKyFINo4Be76MFTL NqCHk/56opL8f0qzi2eLofl41wigk+rQUF9sOZsxkR1/lywf8f0cxItE+s7FS2DTfq W0fn+hsxZrpWQ== From: SJ Park To: Cc: SJ Park , Andrew Morton , Brendan Higgins , David Gow , damon@lists.linux.dev, kunit-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH v1.2 09/12] mm/damon/tests/core-kunit: test damon_nr_samples_per_aggr() Date: Wed, 29 Jul 2026 07:02:49 -0700 Message-ID: <20260729140253.87753-10-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260729140253.87753-1-sj@kernel.org> References: <20260729140253.87753-1-sj@kernel.org> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit damon_max_nr_accesses(), which is a previous version of damon_nr_samples_per_aggr() before the renaming, was wrongly returning zero or random overflowed values for extreme intervals setup. Commit 35d4a3cf70a8 ("mm/damon/ops-common: handle extreme intervals in damon_hot_score()") updated the function to return correct or more valid values. Add a kunit test to ensure it is working as expected. Signed-off-by: SJ Park --- mm/damon/tests/core-kunit.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h index 252d81c30d6f1..c7bda8aadef3f 100644 --- a/mm/damon/tests/core-kunit.h +++ b/mm/damon/tests/core-kunit.h @@ -619,6 +619,27 @@ static void damon_test_set_regions(struct kunit *test) (struct damon_addr_range[]){}, 0, -EINVAL); } +static void damon_test_nr_samples_per_aggr(struct kunit *test) +{ + struct damon_attrs attrs = { + .sample_interval = 0, + .aggr_interval = 0, + }; + + /* Zero aggregation interval doesn't cause division by zero */ + KUNIT_EXPECT_EQ(test, damon_nr_samples_per_aggr(&attrs), 1); + + /* + * Too large aggregation interval on 64 bit system doesn't cause + * overflow + */ + if (ULONG_MAX > UINT_MAX) { + attrs.aggr_interval = (unsigned long)UINT_MAX + 1; + KUNIT_EXPECT_EQ(test, damon_nr_samples_per_aggr(&attrs), + UINT_MAX); + } +} + static void damon_test_update_monitoring_result(struct kunit *test) { struct damon_attrs old_attrs = { @@ -1670,6 +1691,7 @@ static struct kunit_case damon_test_cases[] = { 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_samples_per_aggr), KUNIT_CASE(damon_test_update_monitoring_result), KUNIT_CASE(damon_test_set_attrs), KUNIT_CASE(damon_test_mvsum), -- 2.47.3