Re: [take23 3/5] kevent: poll/select() notifications.

Evgeniy Polyakov
2006-11-08T17:06:13Z

On Wed, Nov 08, 2006 at 11:45:54AM +0300, Evgeniy Polyakov (johnpol@2ka.mipt.ru) wrote:
> > Are you sure you can safely call file->f_op->poll() from inside a callback
> > based wakeup? The low level driver may be calling the wakeup with one of
> > its locks held, and during the file->f_op->poll may be trying to acquire
> > the same lock. I remember there was a discussion about this, and assuming
> > the above not true, made epoll code more complex (and slower, since an
> > extra O(R) loop was needed to fetch events).
>
> Indeed, I have not paid too much attention to poll/select notifications in
> kevent actually. As far as I recall it should be called on behalf of process
> doing kevent_get_event(). I will check and fix if that is not correct.
> Thanks Davide.

Indeed there was a bug.
Actually poll/select patch was broken quite noticebly - patchset did not
include major changes I made for it.
I will put them all into next release.

Thanks again Davide for pointing that out.

--
Evgeniy Polyakov