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| author | Mykyta Yatsenko <yatsenko@meta.com> | 2025-09-25 22:52:30 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-11-13 15:34:08 -0500 |
| commit | 1dee521b9412f19c6d7c2190a4def7474de8c4f4 (patch) | |
| tree | 76836a7a05b55e8bef2cdd6e2365d1e52b36fa43 /tools/testing | |
| parent | 02e73f9f561480364e44f4cc23a80e990f859400 (diff) | |
| download | linux-1dee521b9412f19c6d7c2190a4def7474de8c4f4.tar.gz linux-1dee521b9412f19c6d7c2190a4def7474de8c4f4.tar.bz2 linux-1dee521b9412f19c6d7c2190a4def7474de8c4f4.zip | |
selftests/bpf: Fix flaky bpf_cookie selftest
[ Upstream commit 105eb5dc74109a9f53c2f26c9a918d9347a73595 ]
bpf_cookie can fail on perf_event_open(), when it runs after the task_work
selftest. The task_work test causes perf to lower
sysctl_perf_event_sample_rate, and bpf_cookie uses sample_freq,
which is validated against that sysctl. As a result,
perf_event_open() rejects the attr if the (now tighter) limit is
exceeded.
>From perf_event_open():
if (attr.freq) {
if (attr.sample_freq > sysctl_perf_event_sample_rate)
return -EINVAL;
} else {
if (attr.sample_period & (1ULL << 63))
return -EINVAL;
}
Switch bpf_cookie to use sample_period, which is not checked against
sysctl_perf_event_sample_rate.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250925215230.265501-1-mykyta.yatsenko5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools/testing')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/bpf_cookie.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c index 6befa870434b..f97f560bafb2 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c @@ -450,8 +450,7 @@ static void pe_subtest(struct test_bpf_cookie *skel) attr.size = sizeof(attr); attr.type = PERF_TYPE_SOFTWARE; attr.config = PERF_COUNT_SW_CPU_CLOCK; - attr.freq = 1; - attr.sample_freq = 10000; + attr.sample_period = 100000; pfd = syscall(__NR_perf_event_open, &attr, -1, 0, -1, PERF_FLAG_FD_CLOEXEC); if (!ASSERT_GE(pfd, 0, "perf_fd")) goto cleanup; |