From d4b540544499d90ac81695e21e354cd5c82fa67e Mon Sep 17 00:00:00 2001 From: Mykola Lysenko Date: Tue, 8 Mar 2022 12:04:47 -0800 Subject: Improve perf related BPF tests (sample_freq issue) Linux kernel may automatically reduce kernel.perf_event_max_sample_rate value when running tests in parallel on slow systems. Linux kernel checks against this limit when opening perf event with freq=1 parameter set. The lower bound is 1000. This patch reduces sample_freq value to 1000 in all BPF tests that use sample_freq to ensure they always can open perf event. Signed-off-by: Mykola Lysenko Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220308200449.1757478-2-mykolal@fb.com --- tools/testing/selftests/bpf/prog_tests/perf_link.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/testing/selftests/bpf/prog_tests/perf_link.c') diff --git a/tools/testing/selftests/bpf/prog_tests/perf_link.c b/tools/testing/selftests/bpf/prog_tests/perf_link.c index ede07344f264..224eba6fef2e 100644 --- a/tools/testing/selftests/bpf/prog_tests/perf_link.c +++ b/tools/testing/selftests/bpf/prog_tests/perf_link.c @@ -39,7 +39,7 @@ void serial_test_perf_link(void) attr.type = PERF_TYPE_SOFTWARE; attr.config = PERF_COUNT_SW_CPU_CLOCK; attr.freq = 1; - attr.sample_freq = 4000; + attr.sample_freq = 1000; pfd = syscall(__NR_perf_event_open, &attr, -1, 0, -1, PERF_FLAG_FD_CLOEXEC); if (!ASSERT_GE(pfd, 0, "perf_fd")) goto cleanup; -- cgit v1.2.3