mm/damon/core-test: add a test for damon_update_monitoring_results()

Add a simple unit test for damon_update_monitoring_results() function.

Link: https://lkml.kernel.org/r/20230119013831.1911-4-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/core-test.h

@@ -289,6 +289,35 @@ static void damon_test_set_regions(struct kunit *test)
 	damon_destroy_target(t);
 }
 
+static void damon_test_update_monitoring_result(struct kunit *test)
+{
+	struct damon_attrs old_attrs = {
+		.sample_interval = 10, .aggr_interval = 1000,};
+	struct damon_attrs new_attrs;
+	struct damon_region *r = damon_new_region(3, 7);
+
+	r->nr_accesses = 15;
+	r->age = 20;
+
+	new_attrs = (struct damon_attrs){
+		.sample_interval = 100, .aggr_interval = 10000,};
+	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
+	KUNIT_EXPECT_EQ(test, r->nr_accesses, 15);
+	KUNIT_EXPECT_EQ(test, r->age, 2);
+
+	new_attrs = (struct damon_attrs){
+		.sample_interval = 1, .aggr_interval = 1000};
+	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
+	KUNIT_EXPECT_EQ(test, r->nr_accesses, 150);
+	KUNIT_EXPECT_EQ(test, r->age, 2);
+
+	new_attrs = (struct damon_attrs){
+		.sample_interval = 1, .aggr_interval = 100};
+	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
+	KUNIT_EXPECT_EQ(test, r->nr_accesses, 150);
+	KUNIT_EXPECT_EQ(test, r->age, 20);
+}
+
 static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_target),
 	KUNIT_CASE(damon_test_regions),
@@ -299,6 +328,7 @@ static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_split_regions_of),
 	KUNIT_CASE(damon_test_ops_registration),
 	KUNIT_CASE(damon_test_set_regions),
+	KUNIT_CASE(damon_test_update_monitoring_result),
 	{},
 };