On Wed, 1 Jun 2011 12:49:54 +0300, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > In the (rare) case where new descriptors are used > while virtio_net enables vq callback for the TX vq, > virtio_net uses the number of sg entries in the skb it frees to > calculate how many descriptors in the ring have just been made > available. But this value is an overestimate: with indirect buffers > each skb only uses one descriptor entry, meaning we may wake the queue > only to find we still can't transmit anything. This is a bit misleading. The value is an overestimate, but so is the requirement for 2+MAX_SKB_FRAGS, *unless* we suddenly drop into direct mode due to OOM. Thanks, Rusty. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
