RE: [PATCH] omapfb vsync support

Woodruff, Richard
2006-02-28T12:54:43Z

> > Alternatively, we could disable the IRQ each time, if it's not a too
> > heavy operation?
>
> Maybe just have a use count and decrement it in
omapfb_wait_for_vsync()
> at wake up time... If you know how many users are in your queue you
> should know how many to decrement it by. If a process is killed I'm
not
> sure how that plays out, the kernel likely just closes paths and
> probably silently de-queues a process where ever it happens to be
stuck.

Actually, a lock and an enable flag are probably enough. Everyone in
your queued gets woke up upon wake_up anyway, counting probably doesn't
add anything but overhead. Having a suspend lockout on D2/D3 is
probably still worth having. However, that becomes a bit more coupled
with power management and that seems to be a bit of a moving target.

Regards,
Richard W.