[PATCH 0/2] mm/damon: test and document power-of-2 min_region_sz requirement

[PATCH 0/2] mm/damon: test and document power-of-2 min_region_sz requirement

[SeongJae Park]

Since commit c80f46ac228b ("mm/damon/core: disallow non-power of two
min_region_sz"), min_region_sz is always restricted to be a power of
two.  Add a kunit test to confirm the functionality.  Also, the change
adds a restriction to addr_unit parameter.  Clarify it on the document.

SeongJae Park (2):
  mm/damon/tests/core-kunit: add a test for damon_commit_ctx()
  Docs/mm/damon/design: document the power-of-two limitation for
    addr_unit

 Documentation/mm/damon/design.rst |  2 ++
 mm/damon/tests/core-kunit.h       | 22 ++++++++++++++++++++++
 2 files changed, 24 insertions(+)


base-commit: 4380f0b6370ead5000b8d155b25a86cb59d68c06
-- 
2.47.3

[PATCH 1/2] mm/damon/tests/core-kunit: add a test for damon_commit_ctx()

[SeongJae Park]

Add a kunit test for confirming the change that is made on commit
c80f46ac228b ("mm/damon/core: disallow non-power of two min_region_sz")
functions as expected.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 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 44a983fca9501..65181c6dac1b4 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -1060,6 +1060,27 @@ static void damon_test_commit_target_regions(struct kunit *test)
 			(unsigned long[][2]) {{3, 8}, {8, 10}}, 2);
 }
 
+static void damon_test_commit_ctx(struct kunit *test)
+{
+	struct damon_ctx *src, *dst;
+
+	src = damon_new_ctx();
+	if (!src)
+		kunit_skip(test, "src alloc fail");
+	dst = damon_new_ctx();
+	if (!dst) {
+		damon_destroy_ctx(src);
+		kunit_skip(test, "dst alloc fail");
+	}
+	/* Only power of two min_region_sz is allowed. */
+	src->min_region_sz = 4096;
+	KUNIT_EXPECT_EQ(test, damon_commit_ctx(dst, src), 0);
+	src->min_region_sz = 4095;
+	KUNIT_EXPECT_EQ(test, damon_commit_ctx(dst, src), -EINVAL);
+	damon_destroy_ctx(src);
+	damon_destroy_ctx(dst);
+}
+
 static void damos_test_filter_out(struct kunit *test)
 {
 	struct damon_target *t;
@@ -1316,6 +1337,7 @@ static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damos_test_commit_pageout),
 	KUNIT_CASE(damos_test_commit_migrate_hot),
 	KUNIT_CASE(damon_test_commit_target_regions),
+	KUNIT_CASE(damon_test_commit_ctx),
 	KUNIT_CASE(damos_test_filter_out),
 	KUNIT_CASE(damon_test_feed_loop_next_input),
 	KUNIT_CASE(damon_test_set_filters_default_reject),
-- 
2.47.3