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sunvnet: Remove irqsave/irqrestore on vio.lock
After the NAPIfication of sunvnet, we no longer need to synchronize by doing irqsave/restore on vio.lock in the I/O fastpath. NAPI ->poll() is non-reentrant, so all RX processing occurs strictly in a serialized environment. TX reclaim is done in NAPI context, so the netif_tx_lock can be used to serialize critical sections between Tx and Rx paths. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
2a968dd8f7
commit
13b13dd97c
1 changed files with 5 additions and 25 deletions
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@ -842,18 +842,6 @@ struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
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return NULL;
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}
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struct vnet_port *tx_port_find(struct vnet *vp, struct sk_buff *skb)
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{
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struct vnet_port *ret;
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unsigned long flags;
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spin_lock_irqsave(&vp->lock, flags);
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ret = __tx_port_find(vp, skb);
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spin_unlock_irqrestore(&vp->lock, flags);
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return ret;
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}
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static struct sk_buff *vnet_clean_tx_ring(struct vnet_port *port,
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unsigned *pending)
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{
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@ -914,11 +902,10 @@ static void vnet_clean_timer_expire(unsigned long port0)
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struct vnet_port *port = (struct vnet_port *)port0;
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struct sk_buff *freeskbs;
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unsigned pending;
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unsigned long flags;
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spin_lock_irqsave(&port->vio.lock, flags);
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netif_tx_lock(port->vp->dev);
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freeskbs = vnet_clean_tx_ring(port, &pending);
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spin_unlock_irqrestore(&port->vio.lock, flags);
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netif_tx_unlock(port->vp->dev);
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vnet_free_skbs(freeskbs);
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@ -971,7 +958,6 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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struct vnet_port *port = NULL;
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struct vio_dring_state *dr;
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struct vio_net_desc *d;
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unsigned long flags;
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unsigned int len;
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struct sk_buff *freeskbs = NULL;
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int i, err, txi;
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@ -984,7 +970,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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goto out_dropped;
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rcu_read_lock();
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port = tx_port_find(vp, skb);
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port = __tx_port_find(vp, skb);
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if (unlikely(!port))
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goto out_dropped;
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@ -1020,8 +1006,6 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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goto out_dropped;
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}
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spin_lock_irqsave(&port->vio.lock, flags);
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dr = &port->vio.drings[VIO_DRIVER_TX_RING];
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if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
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if (!netif_queue_stopped(dev)) {
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@ -1055,7 +1039,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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(LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_RW));
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if (err < 0) {
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netdev_info(dev, "tx buffer map error %d\n", err);
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goto out_dropped_unlock;
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goto out_dropped;
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}
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port->tx_bufs[txi].ncookies = err;
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@ -1108,7 +1092,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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netdev_info(dev, "TX trigger error %d\n", err);
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d->hdr.state = VIO_DESC_FREE;
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dev->stats.tx_carrier_errors++;
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goto out_dropped_unlock;
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goto out_dropped;
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}
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ldc_start_done:
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@ -1124,7 +1108,6 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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netif_wake_queue(dev);
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}
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spin_unlock_irqrestore(&port->vio.lock, flags);
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(void)mod_timer(&port->clean_timer, jiffies + VNET_CLEAN_TIMEOUT);
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rcu_read_unlock();
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@ -1132,9 +1115,6 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
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return NETDEV_TX_OK;
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out_dropped_unlock:
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spin_unlock_irqrestore(&port->vio.lock, flags);
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out_dropped:
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if (pending)
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(void)mod_timer(&port->clean_timer,
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