[PATCH v4 08/10] kunit: string-stream: Add test for freeing resource-managed string_stream

Richard Fitzgerald
2023-08-14T13:24:26Z

string_stream_resource_free_test() allocates a resource-managed
string_stream and tests that raw_free_string_stream() is called when
the test resources are cleaned up.

string_stream_init_test() is extended to test allocating a
string_stream that is not resource-managed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
lib/kunit/string-stream-test.c | 117 ++++++++++++++++++++++++++++++++-
lib/kunit/string-stream.c | 3 +
2 files changed, 119 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/string-stream-test.c b/lib/kunit/string-stream-test.c
index 437aa4b3179d..05bfade2bd8a 100644
--- a/lib/kunit/string-stream-test.c
+++ b/lib/kunit/string-stream-test.c
@@ -6,16 +6,27 @@
* Author: Brendan Higgins <brendanhiggins@google.com>
*/

+#include <kunit/static_stub.h>
#include <kunit/test.h>
#include <linux/slab.h>

#include "string-stream.h"

+struct string_stream_test_priv {
+ struct string_stream *raw_stream;
+
+ /* For testing resource-managed free */
+ struct string_stream *freed_stream;
+ bool stream_free_again;
+};
+
/* string_stream object is initialized correctly. */
static void string_stream_init_test(struct kunit *test)
{
+ struct string_stream_test_priv *priv = test->priv;
struct string_stream *stream;

+ /* Resource-managed initialization */
stream = alloc_string_stream(test, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream);

@@ -26,6 +37,86 @@ static void string_stream_init_test(struct kunit *test)
KUNIT_EXPECT_FALSE(test, stream->append_newlines);

KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream));
+
+ free_string_stream(test, stream);
+
+ /*
+ * Raw initialization. This allocation is not resource-managed
+ * so store it in priv->raw_stream to be cleaned up by the
+ * exit function.
+ */
+ priv->raw_stream = raw_alloc_string_stream(GFP_KERNEL);
+ stream = priv->raw_stream;
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream);
+
+ KUNIT_EXPECT_EQ(test, stream->length, 0);
+ KUNIT_EXPECT_TRUE(test, list_empty(&stream->fragments));
+ KUNIT_EXPECT_PTR_EQ(test, stream->test, NULL);
+ KUNIT_EXPECT_EQ(test, stream->gfp, GFP_KERNEL);
+ KUNIT_EXPECT_FALSE(test, stream->append_newlines);
+
+ KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream));
+}
+
+static void string_stream_raw_free_string_stream_stub(struct string_stream *stream)
+{
+ struct kunit *fake_test = kunit_get_current_test();
+ struct string_stream_test_priv *priv = fake_test->priv;
+
+ if (priv->freed_stream)
+ priv->stream_free_again = true;
+
+ priv->freed_stream = stream;
+
+ /*
+ * Avoid calling deactivate_static_stub() or changing
+ * current->kunit_test during cleanup. Leave the stream to
+ * be freed during the test exit.
+ */
+}
+
+/* string_stream object is freed when test is cleaned up. */
+static void string_stream_resource_free_test(struct kunit *test)
+{
+ struct string_stream_test_priv *priv = test->priv;
+ struct kunit *fake_test;
+ struct string_stream *stream;
+
+ fake_test = kunit_kzalloc(test, sizeof(*fake_test), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_test);
+
+ kunit_init_test(fake_test, "string_stream_fake_test", NULL);
+ fake_test->priv = priv;
+
+ /*
+ * Activate stub before creating string_stream so the
+ * string_stream will be cleaned up first.
+ */
+ priv->freed_stream = NULL;
+ priv->stream_free_again = false;
+ kunit_activate_static_stub(fake_test,
+ raw_free_string_stream,
+ string_stream_raw_free_string_stream_stub);
+
+ stream = alloc_string_stream(fake_test, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream);
+
+ /*
+ * Ensure the stream is freed when this test terminates.
+ */
+ priv->raw_stream = stream;
+
+ /* Set current->kunit_test to fake_test so the static stub will be called. */
+ current->kunit_test = fake_test;
+
+ /* Cleanup test - the stub function should be called */
+ kunit_cleanup(fake_test);
+
+ /* Set current->kunit_test back to current test. */
+ current->kunit_test = test;
+
+ KUNIT_EXPECT_PTR_EQ(test, priv->freed_stream, stream);
+ KUNIT_EXPECT_FALSE(test, priv->stream_free_again);
}

/*
@@ -279,8 +370,30 @@ static void string_stream_auto_newline_test(struct kunit *test)
"One\nTwo\nThree\nFour\nFive\nSix\nSeven\n\nEight\n");
}

+static int string_stream_test_init(struct kunit *test)
+{
+ struct string_stream_test_priv *priv;
+
+ priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ test->priv = priv;
+
+ return 0;
+}
+
+static void string_stream_test_exit(struct kunit *test)
+{
+ struct string_stream_test_priv *priv = test->priv;
+
+ if (priv && priv->raw_stream)
+ raw_free_string_stream(priv->raw_stream);
+}
+
static struct kunit_case string_stream_test_cases[] = {
KUNIT_CASE(string_stream_init_test),
+ KUNIT_CASE(string_stream_resource_free_test),
KUNIT_CASE(string_stream_line_add_test),
KUNIT_CASE(string_stream_variable_length_line_test),
KUNIT_CASE(string_stream_append_test),
@@ -292,6 +405,8 @@ static struct kunit_case string_stream_test_cases[] = {

static struct kunit_suite string_stream_test_suite = {
.name = "string-stream-test",
- .test_cases = string_stream_test_cases
+ .test_cases = string_stream_test_cases,
+ .init = string_stream_test_init,
+ .exit = string_stream_test_exit,
};
kunit_test_suites(&string_stream_test_suite);
diff --git a/lib/kunit/string-stream.c b/lib/kunit/string-stream.c
index 06104a729b45..1b55ac1be2e5 100644
--- a/lib/kunit/string-stream.c
+++ b/lib/kunit/string-stream.c
@@ -6,6 +6,7 @@
* Author: Brendan Higgins <brendanhiggins@google.com>
*/

+#include <kunit/static_stub.h>
#include <kunit/test.h>
#include <linux/list.h>
#include <linux/slab.h>
@@ -167,6 +168,8 @@ bool string_stream_is_empty(struct string_stream *stream)

void raw_free_string_stream(struct string_stream *stream)
{
+ KUNIT_STATIC_STUB_REDIRECT(raw_free_string_stream, stream);
+
string_stream_clear(stream);
kfree(stream);
}
--
2.30.2