Re: [PATCH v8 net-next 5/7] net: simple poll/select low latency socketpoll

[Eliezer Tamir]

On 03/06/2013 16:15, Eric Dumazet wrote:
> On Mon, 2013-06-03 at 11:02 +0300, Eliezer Tamir wrote:
> >   	sock = file->private_data;
> > -	return sock->ops->poll(file, sock, wait);
> > +
> > +	poll_result = sock->ops->poll(file, sock, wait);
> > +
> > +	if (!(poll_result & (POLLRDNORM | POLLERR | POLLRDHUP | POLLHUP)) &&
> > +		sk_valid_ll(sock->sk) && sk_poll_ll(sock->sk, 1))
> > +			poll_result = sock->ops->poll(file, sock, NULL);
> > +
> > +	return poll_result;
> >   }
> >
> >   static int sock_mmap(struct file *file, struct vm_area_struct *vma)
>
>
> In fact, for TCP, POLLOUT event being ready can also be triggered by
> incoming messages, as the ACK might allow the user application to push
> more data in the write queue.
>
> And you might check wait->_key to avoid testing flags that user is not
> interested into.

yes, comparing to _key is more correct.
In any case this needs to be completely rewritten for support for
working well with a large number of sockets.

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