lkml.org 
[lkml]   [2006]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: accept()ing socket connections with level triggered epoll
On Wed, 26 Apr 2006, kyle@pbx.org wrote:

> I think I may have found a bug in Linux's implementation of epoll. My
> program creates a server socket that listens for incoming SOCK_STREAM
> connections. It uses epoll to wait for notification of a new connection
> (and also to handle the client sockets). While the client sockets use edge
> triggered epoll, for performance reasons, the server socket uses level
> triggered epoll.
>
> I have found that when I open connections to my program very quickly, it is
> sometimes possible to call accept more than once before reaching the point
> where no more connections are available and EAGAIN is returned. If I return
> to epoll_wait without accepting all of the available connections, I should
> immediately be notified that a read is still available on the server socket,
> since I am using level triggered epoll for that descriptor (at least that is
> my understanding of how all of this is supposed to work ;). However, epoll
> does not make this notification. Even if the program accepts further
> incoming connections, the missed connection is never accepted, and
> eventually times out on the client side.
>
> Kernel version is 2.6.9. I can provide test code if needed.

Correct, if it's LT you have to get the event because before returning
from epoll_wait(), the event is automatically re-armed if f_op->poll()
returns it. Can you post the *minimal* test code for this case?



- Davide


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-04-26 23:17    [W:0.042 / U:7.388 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site