Hi guys,
separating that discussion out since Daniel had a rather interesting
idea here.
Am 22.05.21 um 22:05 schrieb Daniel Stone:
[SNIP]
Anyway, the problem with syncobj is that the ioctl to wait for a
sync_file to materialise for a given timeline point only allows us to
block with a timeout; this is a non-starter, because we need something
which fits into epoll. The most optimal case is returning a new
eventfd or similar which signals when a given timeline point becomes
available or signaled, but in extremis a syncobj FD becoming readable
when any activity which would change the result of any zero-timeout
wait on that syncobj is more or less workable.
I think the tricky part is to epoll for a certain value.
Not sure how eventfd is supposed to work, but IIRC we don't have the
functionality to poll for a certain value/offset etc to become available.
We could of course create a separate fd for each requested value to poll
for thought, but that sounds like a bit much overhead to me.
Apart from that this is a really interesting idea.
Regards,
Christian.
