On Sat, Oct 10, 2026 at 10:22:45PM +0800, Jia Jia wrote:
> An RX lock batch still looks up the socket for every packet and takes a
> temporary lookup reference, even though the batch already holds a reference
> to the locked socket.
>
> Record the network namespace and packet address tuple when a batch starts.
> Reuse the batch socket for later STREAM/RW packets with the same tuple, and
> release the batch before looking up a different flow.
>
> The cached path still traces every packet, takes an skb owner reference,
> validates socket state, source and transport, updates credit, and runs the
> receive state machine. Only the socket table lookup and its temporary
> reference are skipped.
>
> Signed-off-by: Jia Jia <[email protected]>
> ---
> include/linux/virtio_vsock.h | 3 ++
> net/vmw_vsock/virtio_transport_common.c | 58 +++++++++++++++----------
> 2 files changed, 38 insertions(+), 23 deletions(-)
>
> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> index 26dde6909c4e..d6528681e052 100644
> --- a/include/linux/virtio_vsock.h
> +++ b/include/linux/virtio_vsock.h
> @@ -287,6 +287,9 @@ struct virtio_transport_rx_batch {
> struct sock *sk;
> unsigned int pkts;
> size_t bytes;
> + struct net *net;
> + struct sockaddr_vm src;
> + struct sockaddr_vm dst;
> };
>
> void virtio_transport_recv_pkt_batch(struct virtio_transport *t,
> diff --git a/net/vmw_vsock/virtio_transport_common.c
> b/net/vmw_vsock/virtio_transport_common.c
> index e67dfcaa279c..73e5c7dfe8b4 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -1977,6 +1977,7 @@ void virtio_transport_rx_batch_finish(struct
> virtio_transport_rx_batch *batch)
> batch->sk = NULL;
> batch->pkts = 0;
> batch->bytes = 0;
> + batch->net = NULL;
>
> if (!sk)
> return;
> @@ -2008,6 +2009,37 @@ void virtio_transport_recv_pkt_batch(struct
> virtio_transport *t,
> virtio_transport_recv_pkt_init_addrs(skb, &src, &dst);
> virtio_transport_trace_recv_pkt(skb, &src, &dst);
>
> + if (batch->sk) {
> + if (batch->net == net &&
> + vsock_addr_equals_addr(&batch->src, &src) &&
> + vsock_addr_equals_addr(&batch->dst, &dst) &&
> + virtio_transport_recv_pkt_batchable(t, batch->sk)) {
> + sk = batch->sk;
> + if (!skb_set_owner_sk_safe(skb, sk)) {
> + WARN_ONCE(1, "receiving vsock socket has
> sk_refcnt == 0\n");
> + virtio_transport_rx_batch_finish(batch);
> + kfree_skb(skb);
> + return;
> + }
> +
> + ctx = (struct virtio_transport_rx_pkt_ctx) {
> + .net = net,
> + .src = &src,
> + .dst = &dst,
> + .batchable = &batchable,
> + };
> + free_pkt = virtio_transport_recv_pkt_locked(t, skb, sk,
> &ctx);
> +
> + if (!batchable)
> + virtio_transport_rx_batch_finish(batch);
> + if (free_pkt)
> + kfree_skb(skb);
> + return;
> + }
> +
> + virtio_transport_rx_batch_finish(batch);
> + }
> +
> sk = virtio_transport_recv_pkt_find_socket(skb, &src, &dst, net);
> if (!sk) {
> virtio_transport_rx_batch_finish(batch);
> @@ -2018,33 +2050,10 @@ void virtio_transport_recv_pkt_batch(struct
> virtio_transport *t,
>
> if (!skb_set_owner_sk_safe(skb, sk)) {
> WARN_ONCE(1, "receiving vsock socket has sk_refcnt == 0\n");
> - virtio_transport_rx_batch_finish(batch);
> kfree_skb(skb);
> return;
> }
>
> - if (batch->sk && batch->sk != sk) {
> - /* Never acquire a second socket lock. */
> - virtio_transport_rx_batch_finish(batch);
> - }
> -
> - if (batch->sk == sk) {
> - /* Keep the batch reference; drop this packet's lookup
> reference. */
> - sock_put(sk);
> - ctx = (struct virtio_transport_rx_pkt_ctx) {
> - .net = net,
> - .src = &src,
> - .dst = &dst,
> - .batchable = &batchable,
> - };
> - free_pkt = virtio_transport_recv_pkt_locked(t, skb, sk, &ctx);
> - if (!batchable)
> - virtio_transport_rx_batch_finish(batch);
> - if (free_pkt)
> - kfree_skb(skb);
> - return;
> - }
> -
Not sure I love adding code and then removing it in the same series.
Seems like these are asking to be squashed?
> lock_sock(sk);
> /*
> * Sockmap removal restores the native protocol under sk_callback_lock.
> @@ -2063,6 +2072,9 @@ void virtio_transport_recv_pkt_batch(struct
> virtio_transport *t,
> free_pkt = virtio_transport_recv_pkt_locked(t, skb, sk, &ctx);
> if (start_batch && batchable) {
> /* Keep the lookup reference until the batch is released. */
> + batch->net = net;
> + batch->src = src;
> + batch->dst = dst;
Similar to my comment in the other patch, seems these are all in sk
already?
Best,
Bobby
