On Thu, 2019-09-26 at 16:56 +0000, Quinn Tran wrote:
>
> Are you missing a negation in this last line?
> Also, what's the point of adding this loop?
>
> QT: good catch. The idea is to not sleep the full 10Hz, if the
> vref_count already reaches zero or reaches zero under
> 10Hz. Otherwise, loop/wait for 10Hz. We're trying to get NPIV tear
> down to go faster.
AFAIU, wait_event_timeout() returns before the timeout has elapsed, if
the tested condition becomes true _and_ the wait queue is woken up.
Thus the loop shouldn't be necessary. Are you missing a wake_up() call
to vref_waitq somewhere?
Perhaps you should replace all calls to
atomic_dec(&X->vref_count);
with something like
if (atomic_dec_and_test(&X->vref_count))
wake_up(&X->vref_waitq);
??
Martin
