Re: [Jackit-devel] Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4]

Jack O'Quin
2004-11-27T04:18:35Z

Ingo Molnar <mingo@elte.hu> writes:

> if it's possible to 'silently' overrun the next due interrupt (somewhat,
> but not large enough overrun to cause a hard ALSA xrun) then the
> processing delay will i believe be accounted as a 'wakeup delay'. In
> that case to make the delayed_usecs value truly accurate, i'd at least
> add this:
>
> poll_enter = jack_get_microseconds ();
>
> if (poll_enter > driver->poll_next) {
> /*
> * This processing cycle got delayed over
> * the next due interrupt! Do not account this
> * as a wakeup delay:
> */
> driver->poll_next = 0;
> }
>
> but i'd also suggest to put in a counter into that branch so that this
> condition doesnt get lost.

Added the test Ingo suggests plus a new counter (poll_late) to CVS,
JACK version 0.99.13.
--
joq