On Thu, Sep 28, 2017 at 08:09:38AM +0000, Tan, Jianfeng wrote:
> > Actually, the key (and typical) issue of multi-process here is the fds are
> > process specific, while they are stored in the shared memory. That means
> > only one will take effect eventually. Worse, the old ones are lost.
> >
> > So, I think to make it right in this case, you should move the fds from
> > the shared memory and store them in the memory of the corresponding
> > process.
> > If that's done, all processes could have its own valid fds, then every
> > process could do the kick (if that's really necessary).
> >
> > You could check following commit for more info.
> > 553f45932fb7 ("net/virtio: store PCI operators pointer locally")
>
> Have referred to the above solution, but seems not feasible for this case
> since there are too many queues. For example, if we define an array like this:
> int vhost_callfds[index_by_vid][index_by_queue_id];
> The size would be MAX_VHOST_DEVICE * VHOST_MAX_VRING * 8Byte = 2Mbyte.
I think you can do it in a dynamic way, like what we did for vhost_dev
allocation?
--yliu
>
> Instead, can we propose something like process_id to index array located at
> shared memory?
>
> Thanks,
> Jianfeng
