Re: [PATCH v8 4/5] ptr_ring: resize support

Jesper Dangaard Brouer
2016-06-14T12:04:28Z

On Mon, 13 Jun 2016 23:54:45 +0300
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> This adds ring resize support. Seems to be necessary as
> users such as tun allow userspace control over queue size.
>
> If resize is used, this costs us ability to peek at queue without
> consumer lock - should not be a big deal as peek and consumer are
> usually run on the same CPU.
>
> If ring is made bigger, ring contents is preserved. If ring is made
> smaller, extra pointers are passed to an optional destructor callback.
>
> Cleanup function also gains destructor callback such that
> all pointers in queue can be cleaned up.
>
> This changes some APIs but we don't have any users yet,
> so it won't break bisect.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>

--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
Author of http://www.iptv-analyzer.org
LinkedIn: http://www.linkedin.com/in/brouer