selftests/bpf: Add cgroup kfunc / kptr selftests

This patch adds a selftest suite to validate the cgroup kfuncs that were
added in the prior patch.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221122055458.173143-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 125 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
new file mode 100644
index 000000000000..9f4569f7598b
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
+
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+
+#include "cgrp_kfunc_common.h"
+
+char _license[] SEC("license") = "GPL";
+
+int err, pid, invocations;
+
+/* Prototype for all of the program trace events below:
+ *
+ * TRACE_EVENT(cgroup_mkdir,
+ *         TP_PROTO(struct cgroup *cgrp, const char *path),
+ *         TP_ARGS(cgrp, path)
+ */
+
+static bool is_test_kfunc_task(void)
+{
+	int cur_pid = bpf_get_current_pid_tgid() >> 32;
+	bool same = pid == cur_pid;
+
+	if (same)
+		__sync_fetch_and_add(&invocations, 1);
+
+	return same;
+}
+
+SEC("tp_btf/cgroup_mkdir")
+int BPF_PROG(test_cgrp_acquire_release_argument, struct cgroup *cgrp, const char *path)
+{
+	struct cgroup *acquired;
+
+	if (!is_test_kfunc_task())
+		return 0;
+
+	acquired = bpf_cgroup_acquire(cgrp);
+	bpf_cgroup_release(acquired);
+
+	return 0;
+}
+
+SEC("tp_btf/cgroup_mkdir")
+int BPF_PROG(test_cgrp_acquire_leave_in_map, struct cgroup *cgrp, const char *path)
+{
+	long status;
+
+	if (!is_test_kfunc_task())
+		return 0;
+
+	status = cgrps_kfunc_map_insert(cgrp);
+	if (status)
+		err = 1;
+
+	return 0;
+}
+
+SEC("tp_btf/cgroup_mkdir")
+int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path)
+{
+	struct cgroup *kptr;
+	struct __cgrps_kfunc_map_value *v;
+	long status;
+
+	if (!is_test_kfunc_task())
+		return 0;
+
+	status = cgrps_kfunc_map_insert(cgrp);
+	if (status) {
+		err = 1;
+		return 0;
+	}
+
+	v = cgrps_kfunc_map_value_lookup(cgrp);
+	if (!v) {
+		err = 2;
+		return 0;
+	}
+
+	kptr = bpf_kptr_xchg(&v->cgrp, NULL);
+	if (!kptr) {
+		err = 3;
+		return 0;
+	}
+
+	bpf_cgroup_release(kptr);
+
+	return 0;
+}
+
+SEC("tp_btf/cgroup_mkdir")
+int BPF_PROG(test_cgrp_get_release, struct cgroup *cgrp, const char *path)
+{
+	struct cgroup *kptr;
+	struct __cgrps_kfunc_map_value *v;
+	long status;
+
+	if (!is_test_kfunc_task())
+		return 0;
+
+	status = cgrps_kfunc_map_insert(cgrp);
+	if (status) {
+		err = 1;
+		return 0;
+	}
+
+	v = cgrps_kfunc_map_value_lookup(cgrp);
+	if (!v) {
+		err = 2;
+		return 0;
+	}
+
+	kptr = bpf_cgroup_kptr_get(&v->cgrp);
+	if (!kptr) {
+		err = 3;
+		return 0;
+	}
+
+	bpf_cgroup_release(kptr);
+
+	return 0;
+}