Adding selftest that puts kprobe on bpf_fentry_test1 that calls bpf_printk
and invokes bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint
has test[234] programs attached to it.
Because kprobe execution goes through bpf_prog_active check, programs
attached to the tracepoint will fail the recursion check and increment the
recursion_misses stats.
Reviewed-and-tested-by: Song Liu <song@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
.../testing/selftests/bpf/prog_tests/missed.c | 40 ++++++++++++++++++
.../selftests/bpf/progs/missed_tp_recursion.c | 41 +++++++++++++++++++
2 files changed, 81 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/missed_tp_recursion.c
diff --git a/tools/testing/selftests/bpf/prog_tests/missed.c b/tools/testing/selftests/bpf/prog_tests/missed.c
index 54aaf2f8ad8c..24ade11f5c05 100644
--- a/tools/testing/selftests/bpf/prog_tests/missed.c
+++ b/tools/testing/selftests/bpf/prog_tests/missed.c
@@ -2,6 +2,7 @@
#include <test_progs.h>
#include "missed_kprobe.skel.h"
#include "missed_kprobe_recursion.skel.h"
+#include "missed_tp_recursion.skel.h"
/*
* Putting kprobe on bpf_fentry_test1 that calls bpf_kfunc_common_test
@@ -89,10 +90,49 @@ static void test_missed_kprobe_recursion(void)
missed_kprobe_recursion__destroy(skel);
}
+/*
+ * Putting kprobe on bpf_fentry_test1 that calls bpf_printk and invokes
+ * bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint has test[234]
+ * programs attached to it.
+ *
+ * Because kprobe execution goes through bpf_prog_active check, programs
+ * attached to the tracepoint will fail the recursion check and increment
+ * the recursion_misses stats.
+ */
+static void test_missed_tp_recursion(void)
+{
+ LIBBPF_OPTS(bpf_test_run_opts, topts);
+ struct missed_tp_recursion *skel;
+ int err, prog_fd;
+
+ skel = missed_tp_recursion__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "missed_tp_recursion__open_and_load"))
+ goto cleanup;
+
+ err = missed_tp_recursion__attach(skel);
+ if (!ASSERT_OK(err, "missed_tp_recursion__attach"))
+ goto cleanup;
+
+ prog_fd = bpf_program__fd(skel->progs.trigger);
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run");
+ ASSERT_EQ(topts.retval, 0, "test_run");
+
+ ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test1)), 0, "test1_recursion_misses");
+ ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test2)), 1, "test2_recursion_misses");
+ ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test3)), 1, "test3_recursion_misses");
+ ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test4)), 1, "test4_recursion_misses");
+
+cleanup:
+ missed_tp_recursion__destroy(skel);
+}
+
void test_missed(void)
{
if (test__start_subtest("perf_kprobe"))
test_missed_perf_kprobe();
if (test__start_subtest("kprobe_recursion"))
test_missed_kprobe_recursion();
+ if (test__start_subtest("tp_recursion"))
+ test_missed_tp_recursion();
}
diff --git a/tools/testing/selftests/bpf/progs/missed_tp_recursion.c b/tools/testing/selftests/bpf/progs/missed_tp_recursion.c
new file mode 100644
index 000000000000..762385f827c5
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/missed_tp_recursion.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+/*
+ * No tests in here, just to trigger 'bpf_fentry_test*'
+ * through tracing test_run
+ */
+SEC("fentry/bpf_modify_return_test")
+int BPF_PROG(trigger)
+{
+ return 0;
+}
+
+SEC("kprobe/bpf_fentry_test1")
+int test1(struct pt_regs *ctx)
+{
+ bpf_printk("test");
+ return 0;
+}
+
+SEC("tp/bpf_trace/bpf_trace_printk")
+int test2(struct pt_regs *ctx)
+{
+ return 0;
+}
+
+SEC("tp/bpf_trace/bpf_trace_printk")
+int test3(struct pt_regs *ctx)
+{
+ return 0;
+}
+
+SEC("tp/bpf_trace/bpf_trace_printk")
+int test4(struct pt_regs *ctx)
+{
+ return 0;
+}
--
2.41.0
