[PATCH v2 bpf-next 5/7] selftests/bpf: switch test to new attach_perf_event API

Andrii Nakryiko
2019-06-21T04:56:20Z

Use new bpf_program__attach_perf_event() in test previously relying on
direct ioctl manipulations.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
.../bpf/prog_tests/stacktrace_build_id_nmi.c | 24 ++++++++-----------
1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c b/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c
index 1c1a2f75f3d8..c83f16e8eccf 100644
--- a/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c
+++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c
@@ -17,6 +17,7 @@ static __u64 read_perf_max_sample_freq(void)
void test_stacktrace_build_id_nmi(void)
{
int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
+ const char *prog_name = "tracepoint/random/urandom_read";
const char *file = "./test_stacktrace_build_id.o";
int err, pmu_fd, prog_fd;
struct perf_event_attr attr = {
@@ -25,6 +26,7 @@ void test_stacktrace_build_id_nmi(void)
.config = PERF_COUNT_HW_CPU_CYCLES,
};
__u32 key, previous_key, val, duration = 0;
+ struct bpf_program *prog;
struct bpf_object *obj;
char buf[256];
int i, j;
@@ -39,6 +41,10 @@ void test_stacktrace_build_id_nmi(void)
if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
return;

+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK(!prog, "find_prog", "prog '%s' not found\n", prog_name))
+ goto close_prog;
+
pmu_fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
0 /* cpu 0 */, -1 /* group id */,
0 /* flags */);
@@ -47,14 +53,8 @@ void test_stacktrace_build_id_nmi(void)
pmu_fd, errno))
goto close_prog;

- err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
- if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n",
- err, errno))
- goto close_pmu;
-
- err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
- if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n",
- err, errno))
+ err = bpf_program__attach_perf_event(prog, pmu_fd);
+ if (CHECK(err, "attach_perf_event", "err %d\n", err))
goto disable_pmu;

/* find map fds */
@@ -134,8 +134,7 @@ void test_stacktrace_build_id_nmi(void)
* try it one more time.
*/
if (build_id_matches < 1 && retry--) {
- ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
- close(pmu_fd);
+ libbpf_perf_event_disable_and_close(pmu_fd);
bpf_object__close(obj);
printf("%s:WARN:Didn't find expected build ID from the map, retrying\n",
__func__);
@@ -154,10 +153,7 @@ void test_stacktrace_build_id_nmi(void)
*/

disable_pmu:
- ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
-
-close_pmu:
- close(pmu_fd);
+ libbpf_perf_event_disable_and_close(pmu_fd);

close_prog:
bpf_object__close(obj);
--
2.17.1