1 files changed, 64 insertions, 44 deletions

diff --git a/drivers/net/iseries_veth.c b/drivers/net/iseries_veth.c
index 122d60db4ff7..eaff17cc9fb8 100644
--- a/drivers/net/iseries_veth.c
+++ b/drivers/net/iseries_veth.c
@@ -158,10 +158,11 @@ struct veth_port {
         u64 mac_addr;
         HvLpIndexMap lpar_map;
 
-        spinlock_t pending_gate;
-        struct sk_buff *pending_skb;
-        HvLpIndexMap pending_lpmask;
+        /* queue_lock protects the stopped_map and dev's queue. */
+        spinlock_t queue_lock;
+        HvLpIndexMap stopped_map;
 
+        /* mcast_gate protects promiscuous, num_mcast & mcast_addr. */
         rwlock_t mcast_gate;
         int promiscuous;
         int num_mcast;
@@ -174,7 +175,8 @@ static struct net_device *veth_dev[HVMAXARCHITECTEDVIRTUALLANS]; /* = 0 */
 
 static int veth_start_xmit(struct sk_buff *skb, struct net_device *dev);
 static void veth_recycle_msg(struct veth_lpar_connection *, struct veth_msg *);
-static void veth_flush_pending(struct veth_lpar_connection *cnx);
+static void veth_wake_queues(struct veth_lpar_connection *cnx);
+static void veth_stop_queues(struct veth_lpar_connection *cnx);
 static void veth_receive(struct veth_lpar_connection *, struct VethLpEvent *);
 static void veth_release_connection(struct kobject *kobject);
 static void veth_timed_ack(unsigned long ptr);
@@ -221,6 +223,12 @@ static inline struct veth_msg *veth_stack_pop(struct veth_lpar_connection *cnx)
         return msg;
 }
 
+/* You must hold the connection's lock when you call this function. */
+static inline int veth_stack_is_empty(struct veth_lpar_connection *cnx)
+{
+        return cnx->msg_stack_head == NULL;
+}
+
 static inline HvLpEvent_Rc
 veth_signalevent(struct veth_lpar_connection *cnx, u16 subtype,
                  HvLpEvent_AckInd ackind, HvLpEvent_AckType acktype,
@@ -391,12 +399,12 @@ static void veth_handle_int(struct VethLpEvent *event)
                         }
                 }
 
-                if (acked > 0)
+                if (acked > 0) {
                         cnx->last_contact = jiffies;
+                        veth_wake_queues(cnx);
+                }
 
                 spin_unlock_irqrestore(&cnx->lock, flags);
-
-                veth_flush_pending(cnx);
                 break;
         case VethEventTypeFrames:
                 veth_receive(cnx, event);
@@ -492,7 +500,9 @@ static void veth_statemachine(void *p)
                         for (i = 0; i < VETH_NUMBUFFERS; ++i)
                                 veth_recycle_msg(cnx, cnx->msgs + i);
                 }
+
                 cnx->outstanding_tx = 0;
+                veth_wake_queues(cnx);
 
                 /* Drop the lock so we can do stuff that might sleep or
                  * take other locks. */
@@ -501,8 +511,6 @@ static void veth_statemachine(void *p)
                 del_timer_sync(&cnx->ack_timer);
                 del_timer_sync(&cnx->reset_timer);
 
-                veth_flush_pending(cnx);
-
                 spin_lock_irq(&cnx->lock);
 
                 if (cnx->state & VETH_STATE_RESET)
@@ -869,8 +877,9 @@ static struct net_device * __init veth_probe_one(int vlan, struct device *vdev)
 
         port = (struct veth_port *) dev->priv;
 
-        spin_lock_init(&port->pending_gate);
+        spin_lock_init(&port->queue_lock);
         rwlock_init(&port->mcast_gate);
+        port->stopped_map = 0;
 
         for (i = 0; i < HVMAXARCHITECTEDLPS; i++) {
                 HvLpVirtualLanIndexMap map;
@@ -980,6 +989,9 @@ static int veth_transmit_to_one(struct sk_buff *skb, HvLpIndex rlp,
         cnx->last_contact = jiffies;
         cnx->outstanding_tx++;
 
+        if (veth_stack_is_empty(cnx))
+                veth_stop_queues(cnx);
+
         spin_unlock_irqrestore(&cnx->lock, flags);
         return 0;
 
@@ -1023,7 +1035,6 @@ static int veth_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         unsigned char *frame = skb->data;
         struct veth_port *port = (struct veth_port *) dev->priv;
-        unsigned long flags;
         HvLpIndexMap lpmask;
 
         if (! (frame[0] & 0x01)) {
@@ -1040,27 +1051,9 @@ static int veth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 lpmask = port->lpar_map;
         }
 
-        spin_lock_irqsave(&port->pending_gate, flags);
-
-        lpmask = veth_transmit_to_many(skb, lpmask, dev);
+        veth_transmit_to_many(skb, lpmask, dev);
 
-        if (! lpmask) {
-                dev_kfree_skb(skb);
-        } else {
-                if (port->pending_skb) {
-                        veth_error("%s: TX while skb was pending!\n",
-                                   dev->name);
-                        dev_kfree_skb(skb);
-                        spin_unlock_irqrestore(&port->pending_gate, flags);
-                        return 1;
-                }
-
-                port->pending_skb = skb;
-                port->pending_lpmask = lpmask;
-                netif_stop_queue(dev);
-        }
-
-        spin_unlock_irqrestore(&port->pending_gate, flags);
+        dev_kfree_skb(skb);
 
         return 0;
 }
@@ -1093,9 +1086,10 @@ static void veth_recycle_msg(struct veth_lpar_connection *cnx,
         }
 }
 
-static void veth_flush_pending(struct veth_lpar_connection *cnx)
+static void veth_wake_queues(struct veth_lpar_connection *cnx)
 {
         int i;
+
         for (i = 0; i < HVMAXARCHITECTEDVIRTUALLANS; i++) {
                 struct net_device *dev = veth_dev[i];
                 struct veth_port *port;
@@ -1109,19 +1103,45 @@ static void veth_flush_pending(struct veth_lpar_connection *cnx)
                 if (! (port->lpar_map & (1<<cnx->remote_lp)))
                         continue;
 
-                spin_lock_irqsave(&port->pending_gate, flags);
-                if (port->pending_skb) {
-                        port->pending_lpmask =
-                                veth_transmit_to_many(port->pending_skb,
-                                                      port->pending_lpmask,
-                                                      dev);
-                        if (! port->pending_lpmask) {
-                                dev_kfree_skb_any(port->pending_skb);
-                                port->pending_skb = NULL;
-                                netif_wake_queue(dev);
-                        }
+                spin_lock_irqsave(&port->queue_lock, flags);
+
+                port->stopped_map &= ~(1 << cnx->remote_lp);
+
+                if (0 == port->stopped_map && netif_queue_stopped(dev)) {
+                        veth_debug("cnx %d: woke queue for %s.\n",
+                                        cnx->remote_lp, dev->name);
+                        netif_wake_queue(dev);
                 }
-                spin_unlock_irqrestore(&port->pending_gate, flags);
+                spin_unlock_irqrestore(&port->queue_lock, flags);
+        }
+}
+
+static void veth_stop_queues(struct veth_lpar_connection *cnx)
+{
+        int i;
+
+        for (i = 0; i < HVMAXARCHITECTEDVIRTUALLANS; i++) {
+                struct net_device *dev = veth_dev[i];
+                struct veth_port *port;
+
+                if (! dev)
+                        continue;
+
+                port = (struct veth_port *)dev->priv;
+
+                /* If this cnx is not on the vlan for this port, continue */
+                if (! (port->lpar_map & (1 << cnx->remote_lp)))
+                        continue;
+
+                spin_lock(&port->queue_lock);
+
+                netif_stop_queue(dev);
+                port->stopped_map |= (1 << cnx->remote_lp);
+
+                veth_debug("cnx %d: stopped queue for %s, map = 0x%x.\n",
+                                cnx->remote_lp, dev->name, port->stopped_map);
+
+                spin_unlock(&port->queue_lock);
         }
 }