diff options
author | Jianlin Lv <Jianlin.Lv@arm.com> | 2020-08-06 18:42:24 +0800 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-08-06 16:58:42 -0700 |
commit | 929e54a989680c6f134b02293732030b897475dc (patch) | |
tree | 54decdc098e14ce43550eeab1bda534da3efdfc3 /tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c | |
parent | selftests: bpf: Switch off timeout (diff) | |
download | linux-929e54a989680c6f134b02293732030b897475dc.tar.gz linux-929e54a989680c6f134b02293732030b897475dc.tar.bz2 linux-929e54a989680c6f134b02293732030b897475dc.zip |
bpf: Fix compilation warning of selftests
Clang compiler version: 12.0.0
The following warning appears during the selftests/bpf compilation:
prog_tests/send_signal.c:51:3: warning: ignoring return value of ‘write’,
declared with attribute warn_unused_result [-Wunused-result]
51 | write(pipe_c2p[1], buf, 1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
prog_tests/send_signal.c:54:3: warning: ignoring return value of ‘read’,
declared with attribute warn_unused_result [-Wunused-result]
54 | read(pipe_p2c[0], buf, 1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
......
prog_tests/stacktrace_build_id_nmi.c:13:2: warning: ignoring return value
of ‘fscanf’,declared with attribute warn_unused_result [-Wunused-resul]
13 | fscanf(f, "%llu", &sample_freq);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:133:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
133 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:138:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
138 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:143:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
143 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
Add code that fix compilation warning about ignoring return value and
handles any errors; Check return value of library`s API make the code
more secure.
Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200806104224.95306-1-Jianlin.Lv@arm.com
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c')
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c | 4 |
1 files changed, 3 insertions, 1 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 f002e3090d92..11a769e18f5d 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 @@ -6,11 +6,13 @@ static __u64 read_perf_max_sample_freq(void) { __u64 sample_freq = 5000; /* fallback to 5000 on error */ FILE *f; + __u32 duration = 0; f = fopen("/proc/sys/kernel/perf_event_max_sample_rate", "r"); if (f == NULL) return sample_freq; - fscanf(f, "%llu", &sample_freq); + CHECK(fscanf(f, "%llu", &sample_freq) != 1, "Get max sample rate", + "return default value: 5000,err %d\n", -errno); fclose(f); return sample_freq; } |