Re: [tip:timers/core] kselftests: timers: set-timer-lat: Tweak reporting when timer fires early

[John Stultz]

On Tue, Sep 19, 2017 at 6:02 PM, Shuah Khan <shuah@xxxxxxxxxx> wrote:
> Hi Greg,
>
> On 08/20/2017 03:56 AM, tip-bot for Greg Hackmann wrote:
>> Commit-ID:  a524b1184b8e86141d689fa78ad150fbf2db9b4c
>> Gitweb:     http://git.kernel.org/tip/a524b1184b8e86141d689fa78ad150fbf2db9b4c
>> Author:     Greg Hackmann <ghackmann@xxxxxxxxxx>
>> AuthorDate: Tue, 25 Jul 2017 14:36:25 -0700
>> Committer:  John Stultz <john.stultz@xxxxxxxxxx>
>> CommitDate: Thu, 17 Aug 2017 12:14:54 -0700
>>
>> kselftests: timers: set-timer-lat: Tweak reporting when timer fires early
>>
>> Rather than printing an error inside the alarm signal handler, set a
>> flag that we check later.  This keeps the test from spamming the console
>> every time the alarm fires early.  It also fixes the test exiting with
>> error code 0 if this was the only test failure.
>>
>> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
>> Cc: Miroslav Lichvar <mlichvar@xxxxxxxxxx>
>> Cc: Richard Cochran <richardcochran@xxxxxxxxx>
>> Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
>> Cc: Stephen Boyd <stephen.boyd@xxxxxxxxxx>
>> Cc: Shuah Khan <shuah@xxxxxxxxxx>
>> Cc: linux-kselftest@xxxxxxxxxxxxxxx
>> Signed-off-by: Greg Hackmann <ghackmann@xxxxxxxxxx>
>> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
>
> This commit is making the set-timer-lat hang. I reverted this commit
> and there is no hang. Could you please take a look and see if this
> commit should be reverted.
>
> make kselftest as well as make -C tools/testing/selftests/timers run_tests
> hang.
>
> I had to revert the following as well, however a524b1184b8e86141d689fa78ad150fbf2db9b4c
> is the suspect.
>
> Commit-ID:  28be3f8f48cfb3cf024860f042d424cd4824f5f7
> Gitweb:     http://git.kernel.org/tip/28be3f8f48cfb3cf024860f042d424cd4824f5f7
> Author:     Greg Hackmann <ghackmann@xxxxxxxxxx>
> AuthorDate: Tue, 25 Jul 2017 14:36:26 -0700
> Committer:  John Stultz <john.stultz@xxxxxxxxxx>
> CommitDate: Thu, 17 Aug 2017 12:14:58 -0700
>
> kselftests: timers: set-timer-lat: Add one-shot timer test cases
>
> Please let me know how you want to proceed. At the moment kselftest
> run hangs due this test hang.

Huh. I didn't see such a hang in my testing. Let me try to reproduce
and see if I can figure out whats going on.

thanks
-john