Re: [linus:master] [selftests/tracing] c5c413534d: kselftests-bpf.ftrace.ftracetest-ktap._instance_event_trigger_-_test_poll_wait_on_histogram.fail

On Thu, 16 Jul 2026 22:30:11 +0800
kernel test robot <[email protected]> wrote:

> 
> 
> 
> Hello,
> 
> in fact, we found below two test cases randomly failed upon c5c413534d, while
> keep succeed on parent:
> 
> =========================================================================================
> tbox_group/testcase/rootfs/kconfig/compiler/group:
>   igk-rpl-d04/kselftests-bpf/debian-13-x86_64-20250902.cgz/x86_64-rhel-9.4-bpf/gcc-14/ftrace
> 
> 22a78be4123dce81 c5c413534d40eb4c982f1794e62
> ---------------- ---------------------------
>        fail:runs  %reproduction    fail:runs
>            |             |             |
>            :31          52%          16:32    kselftests-bpf.ftrace.ftracetest-ktap._instance_event_trigger_-_test_poll_wait_on_histogram.fail
>            :31          29%           9:32    kselftests-bpf.ftrace.ftracetest-ktap.event_trigger_-_test_poll_wait_on_histogram.fail
> 
> 
> 
> kernel test robot noticed "kselftests-bpf.ftrace.ftracetest-ktap._instance_event_trigger_-_test_poll_wait_on_histogram.fail" on:
> 
> commit: c5c413534d40eb4c982f1794e62813f926aba747 ("selftests/tracing: Have trigger-hist-poll.tc use sched_process_exit")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> 
> [test failed on linux-next/master 49362394dad7df66c274c867a271394c10ca2bb8]

Hmm, this seems like a scheduler (event) behavior is different from what
the test expected.

Steve, I think we should use another deterministic events.

Thank you,

-- 
Masami Hiramatsu (Google) <[email protected]>