[v2,bpf-next,9/9,DONOTAPPLY] Revert "selftests/bpf: Disable newly-added refcounted_kptr_races test"

Commit Message

Dave Marchevsky June 2, 2023, 2:26 a.m. UTC

This patch reverts the previous patch's disabling of
refcounted_kptr_races selftest. It is included with the series so that
BPF CI will be able to run the test. This patch should not be applied -
followups which fix remaining bpf_refcount issues will re-enable this
test.

Signed-off-by: Dave Marchevsky <[e-mail]>
---
 .../bpf/prog_tests/refcounted_kptr.c          | 100 ++++++++++++++++++
 1 file changed, 100 insertions(+)

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/refcounted_kptr.c b/tools/testing/selftests/bpf/prog_tests/refcounted_kptr.c
index 6a53f304f3e4..e7fcc1dd8864 100644
--- a/tools/testing/selftests/bpf/prog_tests/refcounted_kptr.c
+++ b/tools/testing/selftests/bpf/prog_tests/refcounted_kptr.c
@@ -18,3 +18,103 @@  void test_refcounted_kptr_fail(void)
 {
 	RUN_TESTS(refcounted_kptr_fail);
 }
+
+static void force_cpu(pthread_t thread, int cpunum)
+{
+	cpu_set_t cpuset;
+	int err;
+
+	CPU_ZERO(&cpuset);
+	CPU_SET(cpunum, &cpuset);
+	err = pthread_setaffinity_np(thread, sizeof(cpuset), &cpuset);
+	if (!ASSERT_OK(err, "pthread_setaffinity_np"))
+		return;
+}
+
+struct refcounted_kptr *skel;
+
+static void *run_unstash_acq_ref(void *unused)
+{
+	LIBBPF_OPTS(bpf_test_run_opts, opts,
+		.data_in = &pkt_v4,
+		.data_size_in = sizeof(pkt_v4),
+		.repeat = 1,
+	);
+	long ret, unstash_acq_ref_fd;
+	force_cpu(pthread_self(), 1);
+
+	unstash_acq_ref_fd = bpf_program__fd(skel->progs.unstash_add_and_acquire_refcount);
+
+	ret = bpf_prog_test_run_opts(unstash_acq_ref_fd, &opts);
+	ASSERT_EQ(opts.retval, 0, "unstash_add_and_acquire_refcount retval");
+	ASSERT_EQ(skel->bss->ref_check_3, 2, "ref_check_3");
+	ASSERT_EQ(skel->bss->ref_check_4, 1, "ref_check_4");
+	ASSERT_EQ(skel->bss->ref_check_5, 0, "ref_check_5");
+	pthread_exit((void *)ret);
+}
+
+void test_refcounted_kptr_races(void)
+{
+	LIBBPF_OPTS(bpf_test_run_opts, opts,
+		.data_in = &pkt_v4,
+		.data_size_in = sizeof(pkt_v4),
+		.repeat = 1,
+	);
+	int ref_acq_lock_fd, ref_acq_unlock_fd, rem_node_lock_fd;
+	int add_stash_fd, remove_tree_fd;
+	pthread_t thread_id;
+	int ret;
+
+	force_cpu(pthread_self(), 0);
+	skel = refcounted_kptr__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "refcounted_kptr__open_and_load"))
+		return;
+
+	add_stash_fd = bpf_program__fd(skel->progs.add_refcounted_node_to_tree_and_stash);
+	remove_tree_fd = bpf_program__fd(skel->progs.remove_refcounted_node_from_tree);
+	ref_acq_lock_fd = bpf_program__fd(skel->progs.unsafe_ref_acq_lock);
+	ref_acq_unlock_fd = bpf_program__fd(skel->progs.unsafe_ref_acq_unlock);
+	rem_node_lock_fd = bpf_program__fd(skel->progs.unsafe_rem_node_lock);
+
+	ret = bpf_prog_test_run_opts(rem_node_lock_fd, &opts);
+	if (!ASSERT_OK(ret, "rem_node_lock"))
+		return;
+
+	ret = bpf_prog_test_run_opts(ref_acq_lock_fd, &opts);
+	if (!ASSERT_OK(ret, "ref_acq_lock"))
+		return;
+
+	ret = bpf_prog_test_run_opts(add_stash_fd, &opts);
+	if (!ASSERT_OK(ret, "add_stash"))
+		return;
+	if (!ASSERT_OK(opts.retval, "add_stash retval"))
+		return;
+
+	ret = pthread_create(&thread_id, NULL, &run_unstash_acq_ref, NULL);
+	if (!ASSERT_OK(ret, "pthread_create"))
+		goto cleanup;
+
+	force_cpu(thread_id, 1);
+
+	/* This program will execute before unstash_acq_ref's refcount_acquire, then
+	 * unstash_acq_ref can proceed after unsafe_unlock
+	 */
+	ret = bpf_prog_test_run_opts(remove_tree_fd, &opts);
+	if (!ASSERT_OK(ret, "remove_tree"))
+		goto cleanup;
+
+	ret = bpf_prog_test_run_opts(ref_acq_unlock_fd, &opts);
+	if (!ASSERT_OK(ret, "ref_acq_unlock"))
+		goto cleanup;
+
+	ret = pthread_join(thread_id, NULL);
+	if (!ASSERT_OK(ret, "pthread_join"))
+		goto cleanup;
+
+	refcounted_kptr__destroy(skel);
+	return;
+cleanup:
+	bpf_prog_test_run_opts(ref_acq_unlock_fd, &opts);
+	refcounted_kptr__destroy(skel);
+	return;
+}