2 files changed, 63 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/core_retro.c b/tools/testing/selftests/bpf/prog_tests/core_retro.c
new file mode 100644
index 000000000000..78e30d3a23d5
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/core_retro.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2020 Facebook
+#define _GNU_SOURCE
+#include <test_progs.h>
+#include "test_core_retro.skel.h"
+
+void test_core_retro(void)
+{
+	int err, zero = 0, res, duration = 0;
+	struct test_core_retro *skel;
+
+	/* load program */
+	skel = test_core_retro__open_and_load();
+	if (CHECK(!skel, "skel_load", "skeleton open/load failed\n"))
+		goto out_close;
+
+	/* attach probe */
+	err = test_core_retro__attach(skel);
+	if (CHECK(err, "attach_kprobe", "err %d\n", err))
+		goto out_close;
+
+	/* trigger */
+	usleep(1);
+
+	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.results), &zero, &res);
+	if (CHECK(err, "map_lookup", "failed to lookup result: %d\n", errno))
+		goto out_close;
+
+	CHECK(res != getpid(), "pid_check", "got %d != exp %d\n", res, getpid());
+
+out_close:
+	test_core_retro__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_core_retro.c b/tools/testing/selftests/bpf/progs/test_core_retro.c
new file mode 100644
index 000000000000..75c60c3c29cf
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_core_retro.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2020 Facebook
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+
+struct task_struct {
+	int tgid;
+} __attribute__((preserve_access_index));
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__uint(max_entries, 1);
+	__type(key, int);
+	__type(value, int);
+} results SEC(".maps");
+
+SEC("tp/raw_syscalls/sys_enter")
+int handle_sys_enter(void *ctx)
+{
+	struct task_struct *task = (void *)bpf_get_current_task();
+	int tgid = BPF_CORE_READ(task, tgid);
+	int zero = 0;
+
+	bpf_map_update_elem(&results, &zero, &tgid, 0);
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";