From 3ebf5212bf042954666b19fe4ff5a98911b08128 Mon Sep 17 00:00:00 2001 From: Song Liu Date: Fri, 7 Apr 2023 12:01:30 -0700 Subject: [PATCH] selftests/bpf: Use PERF_COUNT_HW_CPU_CYCLES event for get_branch_snapshot perf_event with type=PERF_TYPE_RAW and config=0x1b00 turned out to be not reliable in ensuring LBR is active. Thus, test_progs:get_branch_snapshot is not reliable in some systems. Replace it with PERF_COUNT_HW_CPU_CYCLES event, which gives more consistent results. Signed-off-by: Song Liu Signed-off-by: Andrii Nakryiko Acked-by: Jiri Olsa Link: https://lore.kernel.org/bpf/20230407190130.2093736-1-song@kernel.org --- tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c b/tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c index 3948da1..0394a11 100644 --- a/tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c +++ b/tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c @@ -37,8 +37,8 @@ static int create_perf_events(void) /* create perf event */ attr.size = sizeof(attr); - attr.type = PERF_TYPE_RAW; - attr.config = 0x1b00; + attr.type = PERF_TYPE_HARDWARE; + attr.config = PERF_COUNT_HW_CPU_CYCLES; attr.sample_type = PERF_SAMPLE_BRANCH_STACK; attr.branch_sample_type = PERF_SAMPLE_BRANCH_KERNEL | PERF_SAMPLE_BRANCH_USER | PERF_SAMPLE_BRANCH_ANY; -- 2.7.4