mm/damon/core-test: add a kunit test case for ops registration

This commit adds a simple kunit test case for DAMON operations
registration feature.

Link: https://lkml.kernel.org/r/20220419122225.290518-1-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index b4085deb9fa05155610d15043b7d18f91a9c53df..573669566f8467772f211b9f0ead619cd679d4eb 100644 (file)
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -232,6 +232,41 @@ static void damon_test_split_regions_of(struct kunit *test)
        damon_destroy_ctx(c);
 }
 
+static void damon_test_ops_registration(struct kunit *test)
+{
+       struct damon_ctx *c = damon_new_ctx();
+       struct damon_operations ops, bak;
+
+       /* DAMON_OPS_{V,P}ADDR are registered on subsys_initcall */
+       KUNIT_EXPECT_EQ(test, damon_select_ops(c, DAMON_OPS_VADDR), 0);
+       KUNIT_EXPECT_EQ(test, damon_select_ops(c, DAMON_OPS_PADDR), 0);
+
+       /* Double-registration is prohibited */
+       ops.id = DAMON_OPS_VADDR;
+       KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL);
+       ops.id = DAMON_OPS_PADDR;
+       KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL);
+
+       /* Unknown ops id cannot be registered */
+       KUNIT_EXPECT_EQ(test, damon_select_ops(c, NR_DAMON_OPS), -EINVAL);
+
+       /* Registration should success after unregistration */
+       mutex_lock(&damon_ops_lock);
+       bak = damon_registered_ops[DAMON_OPS_VADDR];
+       damon_registered_ops[DAMON_OPS_VADDR] = (struct damon_operations){};
+       mutex_unlock(&damon_ops_lock);
+
+       ops.id = DAMON_OPS_VADDR;
+       KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), 0);
+
+       mutex_lock(&damon_ops_lock);
+       damon_registered_ops[DAMON_OPS_VADDR] = bak;
+       mutex_unlock(&damon_ops_lock);
+
+       /* Check double-registration failure again */
+       KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL);
+}
+
 static struct kunit_case damon_test_cases[] = {
        KUNIT_CASE(damon_test_target),
        KUNIT_CASE(damon_test_regions),
@@ -240,6 +275,7 @@ static struct kunit_case damon_test_cases[] = {
        KUNIT_CASE(damon_test_merge_two),
        KUNIT_CASE(damon_test_merge_regions_of),
        KUNIT_CASE(damon_test_split_regions_of),
+       KUNIT_CASE(damon_test_ops_registration),
        {},
 };