Messages in this thread | | | Date | Thu, 6 Oct 2011 11:19:18 -0200 | From | "Michael S. Tsirkin" <> | Subject | Re: [PATCH 2/5] virtio: support unlocked queue kick |
| |
On Thu, Oct 06, 2011 at 12:15:36PM +1030, Rusty Russell wrote: > On Wed, 05 Oct 2011 15:54:05 -0400, Christoph Hellwig <hch@infradead.org> wrote: > > Split virtqueue_kick to be able to do the actual notification outside the > > lock protecting the virtqueue. This patch was originally done by > > Stefan Hajnoczi, but I can't find the original one anymore and had to > > recreated it from memory. Pointers to the original or corrections for > > the commit message are welcome. > > An alternative to this is to update the ring on every virtqueue_add_buf. > MST discussed this for virtio_net, and I think it's better in general. > > The only reason that it wasn't written that way originally is that the > barriers make add_buf slightly more expensive. > > Cheers, > Rusty.
With event index, I'm not sure that's enough to make the kick lockless anymore.
-- MST
| |