On Thu, 23 Jan 2020 17:14:06 +0000, Haiyang Zhang wrote: > > > Changes: > > > v3: Minor code and comment updates. > > > v2: Added XDP_TX support. Addressed review comments. > > > > How does the locking of the TX path work? You seem to be just calling the > > normal xmit method, but you don't hold the xmit queue lock, so the stack can > > start xmit concurrently, no? > > The netvsc and vmbus can handle concurrent transmits, except the msd > (Multi-Send Data) field which can only be used by one queue. > > I already added a new flag to netvsc_send(), so packets from XDP_TX won't use > the msd. I see, there's a few non-atomic counters there, but maybe that's not a big deal. What frees the skb if the ring is full, and netvsc_send_pkt() returns -EAGAIN? Nothing checks the return value from netvsc_xdp_xmit().
