3 files changed, 26 insertions, 39 deletions

diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 4c76bcb9a879..ae413a2cbee7 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -143,11 +143,7 @@ struct xenvif {
         char rx_irq_name[IFNAMSIZ+4]; /* DEVNAME-rx */
         struct xen_netif_rx_back_ring rx;
         struct sk_buff_head rx_queue;
-        bool rx_queue_stopped;
-        /* Set when the RX interrupt is triggered by the frontend.
-         * The worker thread may need to wake the queue.
-         */
-        bool rx_event;
+        RING_IDX rx_last_skb_slots;
 
         /* This array is allocated seperately as it is large */
         struct gnttab_copy *grant_copy_op;
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index b9de31ea7fc4..301cc037fda8 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -100,7 +100,6 @@ static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
 {
         struct xenvif *vif = dev_id;
 
-        vif->rx_event = true;
         xenvif_kick_thread(vif);
 
         return IRQ_HANDLED;
@@ -133,8 +132,7 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
         /* If the skb is GSO then we'll also need an extra slot for the
          * metadata.
          */
-        if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
-            skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+        if (skb_is_gso(skb))
                 min_slots_needed++;
 
         /* If the skb can't possibly fit in the remaining slots
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 6b62c3eb8e18..438d0c09b7e6 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -240,7 +240,7 @@ static void xenvif_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb,
         struct gnttab_copy *copy_gop;
         struct xenvif_rx_meta *meta;
         unsigned long bytes;
-        int gso_type;
+        int gso_type = XEN_NETIF_GSO_TYPE_NONE;
 
         /* Data must not cross a page boundary. */
         BUG_ON(size + offset > PAGE_SIZE<<compound_order(page));
@@ -299,12 +299,12 @@ static void xenvif_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb,
                 }
 
                 /* Leave a gap for the GSO descriptor. */
-                if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
-                        gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
-                else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
-                        gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
-                else
-                        gso_type = XEN_NETIF_GSO_TYPE_NONE;
+                if (skb_is_gso(skb)) {
+                        if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
+                                gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
+                        else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+                                gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
+                }
 
                 if (*head && ((1 << gso_type) & vif->gso_mask))
                         vif->rx.req_cons++;
@@ -338,19 +338,15 @@ static int xenvif_gop_skb(struct sk_buff *skb,
         int head = 1;
         int old_meta_prod;
         int gso_type;
-        int gso_size;
 
         old_meta_prod = npo->meta_prod;
 
-        if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
-                gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
-                gso_size = skb_shinfo(skb)->gso_size;
-        } else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) {
-                gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
-                gso_size = skb_shinfo(skb)->gso_size;
-        } else {
-                gso_type = XEN_NETIF_GSO_TYPE_NONE;
-                gso_size = 0;
+        gso_type = XEN_NETIF_GSO_TYPE_NONE;
+        if (skb_is_gso(skb)) {
+                if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
+                        gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
+                else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+                        gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
         }
 
         /* Set up a GSO prefix descriptor, if necessary */
@@ -358,7 +354,7 @@ static int xenvif_gop_skb(struct sk_buff *skb,
                 req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++);
                 meta = npo->meta + npo->meta_prod++;
                 meta->gso_type = gso_type;
-                meta->gso_size = gso_size;
+                meta->gso_size = skb_shinfo(skb)->gso_size;
                 meta->size = 0;
                 meta->id = req->id;
         }
@@ -368,7 +364,7 @@ static int xenvif_gop_skb(struct sk_buff *skb,
 
         if ((1 << gso_type) & vif->gso_mask) {
                 meta->gso_type = gso_type;
-                meta->gso_size = gso_size;
+                meta->gso_size = skb_shinfo(skb)->gso_size;
         } else {
                 meta->gso_type = XEN_NETIF_GSO_TYPE_NONE;
                 meta->gso_size = 0;
@@ -476,7 +472,6 @@ static void xenvif_rx_action(struct xenvif *vif)
         unsigned long offset;
         struct skb_cb_overlay *sco;
         bool need_to_notify = false;
-        bool ring_full = false;
 
         struct netrx_pending_operations npo = {
                 .copy  = vif->grant_copy_op,
@@ -486,7 +481,7 @@ static void xenvif_rx_action(struct xenvif *vif)
         skb_queue_head_init(&rxq);
 
         while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) {
-                int max_slots_needed;
+                RING_IDX max_slots_needed;
                 int i;
 
                 /* We need a cheap worse case estimate for the number of
@@ -501,17 +496,19 @@ static void xenvif_rx_action(struct xenvif *vif)
                         size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
                         max_slots_needed += DIV_ROUND_UP(size, PAGE_SIZE);
                 }
-                if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
-                    skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+                if (skb_is_gso(skb) &&
+                   (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
+                    skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6))
                         max_slots_needed++;
 
                 /* If the skb may not fit then bail out now */
                 if (!xenvif_rx_ring_slots_available(vif, max_slots_needed)) {
                         skb_queue_head(&vif->rx_queue, skb);
                         need_to_notify = true;
-                        ring_full = true;
+                        vif->rx_last_skb_slots = max_slots_needed;
                         break;
-                }
+                } else
+                        vif->rx_last_skb_slots = 0;
 
                 sco = (struct skb_cb_overlay *)skb->cb;
                 sco->meta_slots_used = xenvif_gop_skb(skb, &npo);
@@ -522,8 +519,6 @@ static void xenvif_rx_action(struct xenvif *vif)
 
         BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta));
 
-        vif->rx_queue_stopped = !npo.copy_prod && ring_full;
-
         if (!npo.copy_prod)
                 goto done;
 
@@ -1473,8 +1468,8 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif,
 
 static inline int rx_work_todo(struct xenvif *vif)
 {
-        return (!skb_queue_empty(&vif->rx_queue) && !vif->rx_queue_stopped) ||
-                vif->rx_event;
+        return !skb_queue_empty(&vif->rx_queue) &&
+               xenvif_rx_ring_slots_available(vif, vif->rx_last_skb_slots);
 }
 
 static inline int tx_work_todo(struct xenvif *vif)
@@ -1560,8 +1555,6 @@ int xenvif_kthread(void *data)
                 if (!skb_queue_empty(&vif->rx_queue))
                         xenvif_rx_action(vif);
 
-                vif->rx_event = false;
-
                 if (skb_queue_empty(&vif->rx_queue) &&
                     netif_queue_stopped(vif->dev))
                         xenvif_start_queue(vif);