[PATCH bpf-next 3/5] selftests/bpf: libarena: Clean up allocation state before buddy tests

[Emil Tsalapatis <emil@etsalapatis.com>]

Summary: The buddy allocator requires the global BPF buddy allocator
to not be already initialized. However, the test currently merely resets
the allocator before the buddy tests instead of destroying it, and the
test worked because the buddy test happened to run first. Properly
destroy the allocator instead of resetting it.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
---
 tools/testing/selftests/bpf/libarena/src/common.bpf.c  | 6 ++++++
 tools/testing/selftests/bpf/prog_tests/libarena.c      | 8 ++++++--
 tools/testing/selftests/bpf/prog_tests/libarena_asan.c | 8 ++++++--
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/libarena/src/common.bpf.c b/tools/testing/selftests/bpf/libarena/src/common.bpf.c
index 1b4bb19b3c52..569f0f64d518 100644
--- a/tools/testing/selftests/bpf/libarena/src/common.bpf.c
+++ b/tools/testing/selftests/bpf/libarena/src/common.bpf.c
@@ -37,6 +37,12 @@ __weak int arena_buddy_reset(void)
 	return buddy_init(&buddy);
 }
 
+SEC("syscall")
+__weak int arena_buddy_destroy(void)
+{
+	return buddy_destroy(&buddy);
+}
+
 __weak void __arena *arena_malloc(size_t size)
 {
 	return buddy_alloc(&buddy, size);
diff --git a/tools/testing/selftests/bpf/prog_tests/libarena.c b/tools/testing/selftests/bpf/prog_tests/libarena.c
index 61ea68dce410..ba5a5a50f7c0 100644
--- a/tools/testing/selftests/bpf/prog_tests/libarena.c
+++ b/tools/testing/selftests/bpf/prog_tests/libarena.c
@@ -15,7 +15,12 @@ static void run_libarena_test(struct libarena *skel, struct bpf_program *prog,
 {
 	int ret;
 
-	if (!strstr(name, "test_buddy")) {
+	if (strstr(name, "test_buddy")) {
+		/* Buddy tests initialize the allocator directly. */
+		ret = libarena_run_prog(bpf_program__fd(skel->progs.arena_buddy_destroy));
+		if (!ASSERT_OK(ret, "arena_buddy_destroy"))
+			return;
+	} else {
 		ret = libarena_run_prog(bpf_program__fd(skel->progs.arena_buddy_reset));
 		if (!ASSERT_OK(ret, "arena_buddy_reset"))
 			return;
@@ -24,7 +29,6 @@ static void run_libarena_test(struct libarena *skel, struct bpf_program *prog,
 	ret = libarena_run_prog(bpf_program__fd(prog));
 
 	ASSERT_OK(ret, name);
-
 }
 
 static void *run_libarena_parallel_prog(void *arg)
diff --git a/tools/testing/selftests/bpf/prog_tests/libarena_asan.c b/tools/testing/selftests/bpf/prog_tests/libarena_asan.c
index d59d9dd12ef2..f897405f701d 100644
--- a/tools/testing/selftests/bpf/prog_tests/libarena_asan.c
+++ b/tools/testing/selftests/bpf/prog_tests/libarena_asan.c
@@ -17,7 +17,12 @@ static void run_libarena_asan_test(struct libarena_asan *skel,
 {
 	int ret;
 
-	if (!strstr(name, "test_buddy")) {
+	if (strstr(name, "test_buddy")) {
+		/* Buddy tests initialize the allocator directly. */
+		ret = libarena_run_prog(bpf_program__fd(skel->progs.arena_buddy_destroy));
+		if (!ASSERT_OK(ret, "arena_buddy_destroy"))
+			return;
+	} else {
 		ret = libarena_run_prog(bpf_program__fd(skel->progs.arena_buddy_reset));
 		if (!ASSERT_OK(ret, "arena_buddy_reset"))
 			return;
@@ -90,4 +95,3 @@ void test_libarena_asan(void)
 
 	return;
 }
-
-- 
2.54.0