Am 17/08/2022 um 15:10 schrieb Emanuele Giuseppe Esposito:
>
>
> Am 17/08/2022 um 10:04 schrieb Emanuele Giuseppe Esposito:
>>>> + /* protect against read in job_do_yield_locked */
>>>> + JOB_LOCK_GUARD();
>>>> + /* ensure the coroutine is quiescent while the AioContext is changed
>>>> */
>>>> + assert(job->pause_count > 0);
>>> job->pause_count only shows that pausing was requested. The coroutine is
>>> only really quiescent if job->busy == false, too.
>>>
>>> Or maybe job->paused is actually the one you want here.
>> I think job->paused works too.
>>
>
> Actually it doesn't. At least test-block-iothread
> test_propagate_mirror() fails, for both job->paused and !job->busy. I
> think the reason is that if we wait for the flag to be set, we need to
> actually wait that the job gets to the next pause point, because
> job_pause() doesn't really pause the job, it just kind of "schedules"
> the pause on next pause point.
>
> So, either we leave pause_count > 0, or somehow wait (I was thinking
> AIO_WAIT_WHILE(job->paused) but that's probably a very bad idea).
>
> Do you have any suggestion for that?
> Maybe Paolo has a better idea on how to do it?
>
Additional update: after debugging it a little bit, I figured that there
are places where busy=false and paused=false too. This is clear in
job_do_dismiss and not-so-clear in job_exit (at least for me).
I don't know if this is expected or a bug, because it just means that if
we are draining and the job is completing, there is no way to stop it.
Is it a bug? Or am I missing something?
Emanuele
