On 2018/12/26 上午12:41, Michael S. Tsirkin wrote:
Hi! I was just wondering: packed ring batches things naturally. E.g. user_access_begin check descriptor valid smp_rmb copy descriptor user_access_end
But without speculation on the descriptor (which may only work for in-order or even a violation of spec). Only one two access of a single descriptor could be batched. For split ring, we can batch more since we know how many descriptors is pending. (avail_idx - last_avail_idx).
Anything I miss? Thanks
So packed layout should show the gain with this approach. That could be motivation enough to finally enable vhost packed ring support. Thoughts?
