xen-netback: require fewer guest Rx slots when not using GSO

[firefly-linux-kernel-4.4.55.git] / drivers / net / xen-netback / netback.c

diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 42569b994ea84ae03a9ff0d9b88109d3029c4f30..b588b1a08cd4b35c41eca79908ddebeda6b47540 100644 (file)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -149,9 +149,20 @@ static inline pending_ring_idx_t pending_index(unsigned i)
        return i & (MAX_PENDING_REQS-1);
 }
 
-bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue, int needed)
+static int xenvif_rx_ring_slots_needed(struct xenvif *vif)
+{
+       if (vif->gso_mask)
+               return DIV_ROUND_UP(vif->dev->gso_max_size, PAGE_SIZE) + 1;
+       else
+               return DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE);
+}
+
+static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue)
 {
        RING_IDX prod, cons;
+       int needed;
+
+       needed = xenvif_rx_ring_slots_needed(queue->vif);
 
        do {
                prod = queue->rx.sring->req_prod;
@@ -513,7 +524,7 @@ static void xenvif_rx_action(struct xenvif_queue *queue)
 
        skb_queue_head_init(&rxq);
 
-       while (xenvif_rx_ring_slots_available(queue, XEN_NETBK_RX_SLOTS_MAX)
+       while (xenvif_rx_ring_slots_available(queue)
               && (skb = xenvif_rx_dequeue(queue)) != NULL) {
                queue->last_rx_time = jiffies;
 
@@ -1938,8 +1949,7 @@ static bool xenvif_rx_queue_stalled(struct xenvif_queue *queue)
        prod = queue->rx.sring->req_prod;
        cons = queue->rx.req_cons;
 
-       return !queue->stalled
-               && prod - cons < XEN_NETBK_RX_SLOTS_MAX
+       return !queue->stalled && prod - cons < 1
                && time_after(jiffies,
                              queue->last_rx_time + queue->vif->stall_timeout);
 }
@@ -1951,14 +1961,13 @@ static bool xenvif_rx_queue_ready(struct xenvif_queue *queue)
        prod = queue->rx.sring->req_prod;
        cons = queue->rx.req_cons;
 
-       return queue->stalled
-               && prod - cons >= XEN_NETBK_RX_SLOTS_MAX;
+       return queue->stalled && prod - cons >= 1;
 }
 
 static bool xenvif_have_rx_work(struct xenvif_queue *queue)
 {
        return (!skb_queue_empty(&queue->rx_queue)
-               && xenvif_rx_ring_slots_available(queue, XEN_NETBK_RX_SLOTS_MAX))
+               && xenvif_rx_ring_slots_available(queue))
                || (queue->vif->stall_timeout &&
                    (xenvif_rx_queue_stalled(queue)
                     || xenvif_rx_queue_ready(queue)))