EXPERIMENTAL: tevent_kqueue support

[Jeremy Allison]

On Tue, Feb 26, 2013 at 09:39:16PM +0100, Stefan (metze) Metzmacher wrote:
> Am 26.02.2013 20:53, schrieb Jeremy Allison:
> > On Fri, Feb 22, 2013 at 08:46:31PM +0100, Stefan (metze) Metzmacher wrote:
> >>
> >> I spend the last days, fixing some bugs that made autobuild unstable
> >> when we use the poll backend. (About 30-40 private autobuilds...)
> >>
> >> My current work in progress is available under
> >> https://gitweb.samba.org/?p=metze/samba/wip.git;a=shortlog;h=refs/heads/master3-tevent2
> >> and
> >> https://gitweb.samba.org/?p=metze/samba/wip.git;a=shortlog;h=refs/heads/master4-tevent2
> >>
> >> I'll try to add some more tests which test the specific behaviors
> >> regarding triggered events,
> >> e.g. that an event without flags and remaining bytes in the socket
> >> doesn't cause
> >> a 100% cpu loop and similar things.
> > 
> > Ping ! Wonder where you are with this ? I have some OEMs
> > that would like to see this finished so we can get the
> > epoll fix into a winbindd release.
> > 
> > Is there anything more I can do to help ?
> 
> I'll try to propose a patchset for master tomorrow,
> it would be good to get some feedback then.
> 
> In the meantime it would be good if you could take a look
> at my comments to this:
> 
> TODO: Regression test to ensure that a tevent backend can cope with
> separate read/write events on a single fd.
> ...
> TODO: why (fde_wcount - fde_count < 256) ???
>       if we get TEVENT_FD_WRITE we should not block
>       we should also not read if we don't get TEVENT_FD_READ,
>       because this will block.
> 
> https://gitweb.samba.org/?p=metze/samba/wip.git;a=commitdiff;h=610afde264816ece80fcdaca13d39ab3bf86c7b7

That code was already written carefully to do exactly what
it does :-).

Without using threads it's really easy to get yourself
blocked on a pipe. I'll have to do more testing to see
if it's true that writable is cleared when a pipe is
full.

Jeremy.