On Tue, Jul 01, 2025 at 05:45:02PM +0100, Will Deacon wrote:
virtio_vsock_skb_rx_put() only calls skb_put() if the length in the packet header is not zero even though skb_put() handles this case gracefully. Remove the functionally redundant check from virtio_vsock_skb_rx_put() and, on the assumption that this is a worthwhile optimisation for handling credit messages, augment the existing length checks in virtio_transport_rx_work() to elide the call for zero-length payloads. Note that the vhost code already has similar logic in vhost_vsock_alloc_skb(). Signed-off-by: Will Deacon <will@xxxxxxxxxx> --- include/linux/virtio_vsock.h | 4 +--- net/vmw_vsock/virtio_transport.c | 4 +++- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index 36fb3edfa403..eb6980aa19fd 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -52,9 +52,7 @@ static inline void virtio_vsock_skb_rx_put(struct sk_buff *skb) u32 len; len = le32_to_cpu(virtio_vsock_hdr(skb)->len); - - if (len > 0) - skb_put(skb, len); + skb_put(skb, len);
Since the caller is supposed to check the len, can we just pass it as parameter?
So we can avoid the `le32_to_cpu(virtio_vsock_hdr(skb)->len)` here. Thanks, Stefano
} static inline struct sk_buff *virtio_vsock_alloc_skb(unsigned int size, gfp_t mask) diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c index bd2c6aaa1a93..488e6ddc6ffa 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -656,7 +656,9 @@ static void virtio_transport_rx_work(struct work_struct *work) continue; } - virtio_vsock_skb_rx_put(skb); + if (payload_len) + virtio_vsock_skb_rx_put(skb); + virtio_transport_deliver_tap_pkt(skb); virtio_transport_recv_pkt(&virtio_transport, skb); } -- 2.50.0.727.gbf7dc18ff4-goog
