Re: [PATCH v2 bpf-next 3/3] selftests/bpf: add raw_tp_test_run

On Sep 23, 2020, at 12:40 PM, Andrii Nakryiko [off-list ref] wrote:

On Wed, Sep 23, 2020 at 9:55 AM Song Liu [off-list ref] wrote:

quoted

This test runs test_run for raw_tracepoint program. The test covers ctx
input, retval output, and proper handling of cpu_plus field.

Signed-off-by: Song Liu <redacted>
---
.../bpf/prog_tests/raw_tp_test_run.c          | 73 +++++++++++++++++++
.../bpf/progs/test_raw_tp_test_run.c          | 26 +++++++
2 files changed, 99 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c
create mode 100644 tools/testing/selftests/bpf/progs/test_raw_tp_test_run.c

diff --git a/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c b/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c
new file mode 100644
index 0000000000000..3c6523b61afc1
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2019 Facebook */
+#include <test_progs.h>
+#include "bpf/libbpf_internal.h"
+#include "test_raw_tp_test_run.skel.h"
+
+static int duration;
+
+void test_raw_tp_test_run(void)
+{
+       struct bpf_prog_test_run_attr test_attr = {};
+       __u64 args[2] = {0x1234ULL, 0x5678ULL};
+       int comm_fd = -1, err, nr_online, i;
+       int expected_retval = 0x1234 + 0x5678;
+       struct test_raw_tp_test_run *skel;
+       char buf[] = "new_name";
+       bool *online = NULL;
+
+       err = parse_cpu_mask_file("/sys/devices/system/cpu/online", &online,
+                                 &nr_online);
+       if (CHECK(err, "parse_cpu_mask_file", "err %d\n", err))
+               return;
+
+       skel = test_raw_tp_test_run__open_and_load();
+       if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
+               return;

leaking memory here

Good catch! Fixing it in the next version. 

quoted

+       err = test_raw_tp_test_run__attach(skel);
+       if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
+               goto cleanup;
+
+       comm_fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
+       if (CHECK(comm_fd < 0, "open /proc/self/comm", "err %d\n", errno))
+               goto cleanup;
+

[...]

quoted

+SEC("raw_tp/task_rename")
+int BPF_PROG(rename, struct task_struct *task, char *comm)
+{
+
+       count++;
+       if ((unsigned long long) task == 0x1234 &&
+           (unsigned long long) comm == 0x5678) {

you can use shorter __u64?

Sure.