In message <Pine.LNX.4.05.10104011347060.14420-100000@cosmic.nrg.org> you write
:
> > Setting a running task's flags brings races, AFAICT, and checking
> > p->state is NOT sufficient, consider wait_event(): you need p->has_cpu
> > here I think.
>
> My thought here was that if p->state is anything other than TASK_RUNNING
> or TASK_RUNNING|TASK_PREEMPTED, then that task is already at a
> synchonize point,
Right. Theoretically possible to set p->state and not sleep, but it's
not a bad assumption.
> > schedule():
> > if (!(prev->state & TASK_PREEMPTED) && prev->syncing)
> > if (--sync_count == 0) wake_up(&syncing_task);
>
> Don't forget to reset prev->syncing.
Right.
> I agree with you about wait queues, but didn't use them here because
> of the problem of avoiding deadlock on the runqueue lock, which the
> wait queues also use.
And right again. Yeah, it has to be done manually. Ack, can I
retract that Email?
Rusty.
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This archive was generated by hypermail 2b29 : Sat Apr 07 2001 - 21:00:16 EST