Loading...

freebsd-threads@freebsd.org

[Prev] Thread [Next]  |  [Prev] Date [Next]

Thinking about kqueue's and pthread_cond_wait Randall Stewart Wed Feb 10 07:00:08 2010

All:

I have once again come around to thinking about joining pthread cond waits and
kqueue's.

After thinking about it, I think its doable.. with something like a:

pthread_cond_wait_kqueue_np(kev, cond, mtx, ucontext)

Then you can use kev inside a kqueue i.e.
 ret =  kevent(kq, kev, 1, outkev, 1, NULL);

Now when you saw the event:
   if (kev.filter == EVFILT_UMTX){   /* not sure about the name here */
        pthread_kqueue_cond_wait_ret_np(kev, cond, mtx, ucontext)
        do_user_action(cond,mtx, ucontext);
    }

Which would fill in the cond/mtx and ucontext for the user.

Now does this sound useful to anyone.. i.e. should I spend the time
making it work?

The only down side to this is that it would have to allocate memory so
one would need to do a:

    pthread_kqueue_cond_wait_free_np(kev)

After you were done.. and I think it would be best for this to
be a ONE_SHOT.. i.e. you have to re-arm it if the event happens...
Of course until you free it that can be as simple as passing the kev
back down again (i.e. no pthread_cond_wait_kqueue_np() needed).

Comments? Thoughts?  i.e. especially is it worthwhile doing?


Thanks


R
------------------------------
Randall Stewart
803-317-4952 (cell)

_______________________________________________
[EMAIL PROTECTED] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-threads
To unsubscribe, send any mail to "[EMAIL PROTECTED]"