Ronald Bultje wrote:
> Hi all,
>
> I've tried to do some threading magic in lavrec... Basically, sync
> (VIDIOCSYNC) and queue (VIDIOCMCAPTURE) calls go in different threads.
> Problem: I queue all buffers, then sync on each of them, give the buffer
> to a different thread and let it re-queue it. After some time (testing,
> 100% CPU load, so I can't keep up and have to lose frames...), when my
> number of queued buffers starts to decrease to zero and I'm about to
> sync on yet-unqueued buffers, I get a -EINV return value ("invalid
> argument") on my next VIDIOCSYNC.
Yes, of course.
> How threadsafe is v4l supposed to be?
Shouldn't be a problem. If it is you found a bug in the driver's
locking.
> Can I sync on unqueued buffers (assuming, of course, that they'll be
> queued later on - i.e. I'm losing frames)?
You can't.
Gerd
--
#define ENOCLUE 125 /* userland programmer induced race condition */
