diff options
Diffstat (limited to 'drivers/net/xen-netback/interface.c')
| -rw-r--r-- | drivers/net/xen-netback/interface.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index b646039e539b..9cc9f638f442 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -115,6 +115,18 @@ static irqreturn_t xenvif_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } +static void xenvif_wake_queue(unsigned long data) +{ + struct xenvif *vif = (struct xenvif *)data; + + if (netif_queue_stopped(vif->dev)) { + netdev_err(vif->dev, "draining TX queue\n"); + vif->rx_queue_purge = true; + xenvif_kick_thread(vif); + netif_wake_queue(vif->dev); + } +} + static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct xenvif *vif = netdev_priv(dev); @@ -144,8 +156,13 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) * then turn off the queue to give the ring a chance to * drain. */ - if (!xenvif_rx_ring_slots_available(vif, min_slots_needed)) + if (!xenvif_rx_ring_slots_available(vif, min_slots_needed)) { + vif->wake_queue.function = xenvif_wake_queue; + vif->wake_queue.data = (unsigned long)vif; xenvif_stop_queue(vif); + mod_timer(&vif->wake_queue, + jiffies + rx_drain_timeout_jiffies); + } skb_queue_tail(&vif->rx_queue, skb); xenvif_kick_thread(vif); @@ -353,6 +370,8 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, init_timer(&vif->credit_timeout); vif->credit_window_start = get_jiffies_64(); + init_timer(&vif->wake_queue); + dev->netdev_ops = &xenvif_netdev_ops; dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | @@ -531,6 +550,7 @@ void xenvif_disconnect(struct xenvif *vif) xenvif_carrier_off(vif); if (vif->task) { + del_timer_sync(&vif->wake_queue); kthread_stop(vif->task); vif->task = NULL; } @@ -556,12 +576,25 @@ void xenvif_disconnect(struct xenvif *vif) void xenvif_free(struct xenvif *vif) { int i, unmap_timeout = 0; + /* Here we want to avoid timeout messages if an skb can be legitimatly + * stucked somewhere else. Realisticly this could be an another vif's + * internal or QDisc queue. That another vif also has this + * rx_drain_timeout_msecs timeout, but the timer only ditches the + * internal queue. After that, the QDisc queue can put in worst case + * XEN_NETIF_RX_RING_SIZE / MAX_SKB_FRAGS skbs into that another vif's + * internal queue, so we need several rounds of such timeouts until we + * can be sure that no another vif should have skb's from us. We are + * not sending more skb's, so newly stucked packets are not interesting + * for us here. + */ + unsigned int worst_case_skb_lifetime = (rx_drain_timeout_msecs/1000) * + DIV_ROUND_UP(XENVIF_QUEUE_LENGTH, (XEN_NETIF_RX_RING_SIZE / MAX_SKB_FRAGS)); for (i = 0; i < MAX_PENDING_REQS; ++i) { if (vif->grant_tx_handle[i] != NETBACK_INVALID_HANDLE) { unmap_timeout++; schedule_timeout(msecs_to_jiffies(1000)); - if (unmap_timeout > 9 && + if (unmap_timeout > worst_case_skb_lifetime && net_ratelimit()) netdev_err(vif->dev, "Page still granted! Index: %x\n", |