> On Mar 3, 2022, at 7:36 AM, Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
>
> On 3/2/22 10:27 PM, Mykola Lysenko wrote:
>> In send_signal, replace sleep with dummy cpu intensive computation
>> to increase probability of child process being scheduled. Add few
>> more asserts.
>> In find_vma, reduce sample_freq as higher values may be rejected in
>> some qemu setups, remove usleep and increase length of cpu intensive
>> computation.
>> In bpf_cookie, perf_link and perf_branches, reduce sample_freq as
>> higher values may be rejected in some qemu setups
>> Signed-off-by: Mykola Lysenko <mykolal@xxxxxx>
>> Acked-by: Yonghong Song <yhs@xxxxxx>
>> ---
>> .../selftests/bpf/prog_tests/bpf_cookie.c | 2 +-
>> .../testing/selftests/bpf/prog_tests/find_vma.c | 13 ++++++++++---
>> .../selftests/bpf/prog_tests/perf_branches.c | 4 ++--
>> .../selftests/bpf/prog_tests/perf_link.c | 2 +-
>> .../selftests/bpf/prog_tests/send_signal.c | 17 ++++++++++-------
>> .../selftests/bpf/progs/test_send_signal_kern.c | 2 +-
>> 6 files changed, 25 insertions(+), 15 deletions(-)
>> diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
>> index cd10df6cd0fc..0612e79a9281 100644
>> --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
>> +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
>> @@ -199,7 +199,7 @@ static void pe_subtest(struct test_bpf_cookie *skel)
>> 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;
>> diff --git a/tools/testing/selftests/bpf/prog_tests/find_vma.c b/tools/testing/selftests/bpf/prog_tests/find_vma.c
>> index b74b3c0c555a..7cf4feb6464c 100644
>> --- a/tools/testing/selftests/bpf/prog_tests/find_vma.c
>> +++ b/tools/testing/selftests/bpf/prog_tests/find_vma.c
>> @@ -30,12 +30,20 @@ static int open_pe(void)
>> attr.type = PERF_TYPE_HARDWARE;
>> attr.config = PERF_COUNT_HW_CPU_CYCLES;
>> attr.freq = 1;
>> - attr.sample_freq = 4000;
>> + attr.sample_freq = 1000;
>> pfd = syscall(__NR_perf_event_open, &attr, 0, -1, -1, PERF_FLAG_FD_CLOEXEC);
>> return pfd >= 0 ? pfd : -errno;
>> }
>> +static bool find_vma_pe_condition(struct find_vma *skel)
>> +{
>> + return skel->bss->found_vm_exec == 0 ||
>> + skel->data->find_addr_ret != 0 ||
>
> Should this not test for `skel->data->find_addr_ret == -1` ?
It seems that find_addr_ret changes value few times until it gets to 0. I added print statements when value is changed:
find_addr_ret -1 => initial value
find_addr_ret -16 => -EBUSY
find_addr_ret 0 => final value
Hence, in this case I think it is better to wait for the final value. We do have time out in the loop anyways (when “i" reaches 1bn), so test would not get stuck.
TL:DR change in the test that prints these values
- for (i = 0; i < 1000000000 && find_vma_pe_condition(skel); ++i)
+ int find_addr_ret = -1;
+ printf("find_addr_ret %d\n", skel->data->find_addr_ret);
+
+ for (i = 0; i < 1000000000 && find_vma_pe_condition(skel); ++i) {
+ if (find_addr_ret != skel->data->find_addr_ret) {
+ find_addr_ret = skel->data->find_addr_ret;
+ printf("find_addr_ret %d\n", skel->data->find_addr_ret);
+ }
++j;
+ }
+
+ printf("find_addr_ret %d\n", skel->data->find_addr_ret);
>
>> + skel->data->find_zero_ret == -1 ||
>> + strcmp(skel->bss->d_iname, "test_progs") != 0;
>> +}
>> +
> Thanks,
> Daniel
