diff options
Diffstat (limited to 'drivers/net/xen-netback')
-rw-r--r-- | drivers/net/xen-netback/common.h | 39 | ||||
-rw-r--r-- | drivers/net/xen-netback/interface.c | 62 | ||||
-rw-r--r-- | drivers/net/xen-netback/netback.c | 42 | ||||
-rw-r--r-- | drivers/net/xen-netback/xenbus.c | 14 |
4 files changed, 135 insertions, 22 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 34173b5e886f..53c2fa244c64 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -137,6 +137,20 @@ struct xenvif_queue { /* Per-queue data for xenvif */ char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */ struct xenvif *vif; /* Parent VIF */ + /* + * TX/RX common EOI handling. + * When feature-split-event-channels = 0, interrupt handler sets + * NETBK_COMMON_EOI, otherwise NETBK_RX_EOI and NETBK_TX_EOI are set + * by the RX and TX interrupt handlers. + * RX and TX handler threads will issue an EOI when either + * NETBK_COMMON_EOI or their specific bits (NETBK_RX_EOI or + * NETBK_TX_EOI) are set and they will reset those bits. + */ + atomic_t eoi_pending; +#define NETBK_RX_EOI 0x01 +#define NETBK_TX_EOI 0x02 +#define NETBK_COMMON_EOI 0x04 + /* Use NAPI for guest TX */ struct napi_struct napi; /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ @@ -317,6 +331,7 @@ void xenvif_kick_thread(struct xenvif_queue *queue); int xenvif_dealloc_kthread(void *data); +bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread); void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); void xenvif_carrier_on(struct xenvif *vif); @@ -353,4 +368,28 @@ void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue); bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr); void xenvif_mcast_addr_list_free(struct xenvif *vif); +#include <linux/atomic.h> + +static inline int xenvif_atomic_fetch_or(int i, atomic_t *v) +{ + int c, old; + + c = v->counter; + while ((old = cmpxchg(&v->counter, c, c | i)) != c) + c = old; + + return c; +} + +static inline int xenvif_atomic_fetch_andnot(int i, atomic_t *v) +{ + int c, old; + + c = v->counter; + while ((old = cmpxchg(&v->counter, c, c & ~i)) != c) + c = old; + + return c; +} + #endif /* __XEN_NETBACK__COMMON_H__ */ diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 2008c6a02b8a..93f7659e7595 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -76,12 +76,28 @@ int xenvif_schedulable(struct xenvif *vif) !vif->disabled; } +static bool xenvif_handle_tx_interrupt(struct xenvif_queue *queue) +{ + bool rc; + + rc = RING_HAS_UNCONSUMED_REQUESTS(&queue->tx); + if (rc) + napi_schedule(&queue->napi); + return rc; +} + static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; + int old; - if (RING_HAS_UNCONSUMED_REQUESTS(&queue->tx)) - napi_schedule(&queue->napi); + old = xenvif_atomic_fetch_or(NETBK_TX_EOI, &queue->eoi_pending); + WARN(old & NETBK_TX_EOI, "Interrupt while EOI pending\n"); + + if (!xenvif_handle_tx_interrupt(queue)) { + atomic_andnot(NETBK_TX_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } @@ -115,19 +131,48 @@ static int xenvif_poll(struct napi_struct *napi, int budget) return work_done; } +static bool xenvif_handle_rx_interrupt(struct xenvif_queue *queue) +{ + bool rc; + + rc = xenvif_have_rx_work(queue, false); + if (rc) + xenvif_kick_thread(queue); + return rc; +} + static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; + int old; - xenvif_kick_thread(queue); + old = xenvif_atomic_fetch_or(NETBK_RX_EOI, &queue->eoi_pending); + WARN(old & NETBK_RX_EOI, "Interrupt while EOI pending\n"); + + if (!xenvif_handle_rx_interrupt(queue)) { + atomic_andnot(NETBK_RX_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } irqreturn_t xenvif_interrupt(int irq, void *dev_id) { - xenvif_tx_interrupt(irq, dev_id); - xenvif_rx_interrupt(irq, dev_id); + struct xenvif_queue *queue = dev_id; + int old; + bool has_rx, has_tx; + + old = xenvif_atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); + WARN(old, "Interrupt while EOI pending\n"); + + has_tx = xenvif_handle_tx_interrupt(queue); + has_rx = xenvif_handle_rx_interrupt(queue); + + if (!has_rx && !has_tx) { + atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } @@ -555,7 +600,7 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref, if (tx_evtchn == rx_evtchn) { /* feature-split-event-channels == 0 */ - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, queue->name, queue); if (err < 0) @@ -566,7 +611,7 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref, /* feature-split-event-channels == 1 */ snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), "%s-tx", queue->name); - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, queue->tx_irq_name, queue); if (err < 0) @@ -576,7 +621,7 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref, snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), "%s-rx", queue->name); - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, queue->rx_irq_name, queue); if (err < 0) @@ -619,6 +664,7 @@ err_tx_unbind: queue->tx_irq = 0; err_unmap: xenvif_unmap_frontend_rings(queue); + netif_napi_del(&queue->napi); err: return err; } diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 65d37257e033..044478c9adad 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -189,11 +189,15 @@ void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb) spin_lock_irqsave(&queue->rx_queue.lock, flags); - __skb_queue_tail(&queue->rx_queue, skb); - - queue->rx_queue_len += skb->len; - if (queue->rx_queue_len > queue->rx_queue_max) + if (queue->rx_queue_len >= queue->rx_queue_max) { netif_tx_stop_queue(netdev_get_tx_queue(queue->vif->dev, queue->id)); + kfree_skb(skb); + queue->vif->dev->stats.rx_dropped++; + } else { + __skb_queue_tail(&queue->rx_queue, skb); + + queue->rx_queue_len += skb->len; + } spin_unlock_irqrestore(&queue->rx_queue.lock, flags); } @@ -243,6 +247,7 @@ static void xenvif_rx_queue_drop_expired(struct xenvif_queue *queue) break; xenvif_rx_dequeue(queue); kfree_skb(skb); + queue->vif->dev->stats.rx_dropped++; } } @@ -670,6 +675,10 @@ void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue) if (more_to_do) napi_schedule(&queue->napi); + else if (xenvif_atomic_fetch_andnot(NETBK_TX_EOI | NETBK_COMMON_EOI, + &queue->eoi_pending) & + (NETBK_TX_EOI | NETBK_COMMON_EOI)) + xen_irq_lateeoi(queue->tx_irq, 0); } static void tx_add_credit(struct xenvif_queue *queue) @@ -990,7 +999,7 @@ check_frags: * the header's copy failed, and they are * sharing a slot, send an error */ - if (i == 0 && sharedslot) + if (i == 0 && !first_shinfo && sharedslot) xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_ERROR); else @@ -1793,7 +1802,15 @@ int xenvif_tx_action(struct xenvif_queue *queue, int budget) NULL, queue->pages_to_map, nr_mops); - BUG_ON(ret); + if (ret) { + unsigned int i; + + netdev_err(queue->vif->dev, "Map fail: nr %u ret %d\n", + nr_mops, ret); + for (i = 0; i < nr_mops; ++i) + WARN_ON_ONCE(queue->tx_map_ops[i].status == + GNTST_okay); + } } work_done = xenvif_tx_submit(queue); @@ -2010,14 +2027,14 @@ static bool xenvif_rx_queue_ready(struct xenvif_queue *queue) return queue->stalled && prod - cons >= 1; } -static bool xenvif_have_rx_work(struct xenvif_queue *queue) +bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread) { return (!skb_queue_empty(&queue->rx_queue) && xenvif_rx_ring_slots_available(queue)) || (queue->vif->stall_timeout && (xenvif_rx_queue_stalled(queue) || xenvif_rx_queue_ready(queue))) - || kthread_should_stop() + || (test_kthread && kthread_should_stop()) || queue->vif->disabled; } @@ -2048,15 +2065,20 @@ static void xenvif_wait_for_rx_work(struct xenvif_queue *queue) { DEFINE_WAIT(wait); - if (xenvif_have_rx_work(queue)) + if (xenvif_have_rx_work(queue, true)) return; for (;;) { long ret; prepare_to_wait(&queue->wq, &wait, TASK_INTERRUPTIBLE); - if (xenvif_have_rx_work(queue)) + if (xenvif_have_rx_work(queue, true)) break; + if (xenvif_atomic_fetch_andnot(NETBK_RX_EOI | NETBK_COMMON_EOI, + &queue->eoi_pending) & + (NETBK_RX_EOI | NETBK_COMMON_EOI)) + xen_irq_lateeoi(queue->rx_irq, 0); + ret = schedule_timeout(xenvif_rx_queue_timeout(queue)); if (!ret) break; diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index 56ebd8267386..683fd8560f2b 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -697,12 +697,14 @@ static int xen_register_watchers(struct xenbus_device *dev, struct xenvif *vif) return -ENOMEM; snprintf(node, maxlen, "%s/rate", dev->nodename); vif->credit_watch.node = node; + vif->credit_watch.will_handle = NULL; vif->credit_watch.callback = xen_net_rate_changed; err = register_xenbus_watch(&vif->credit_watch); if (err) { pr_err("Failed to set watcher %s\n", vif->credit_watch.node); kfree(node); vif->credit_watch.node = NULL; + vif->credit_watch.will_handle = NULL; vif->credit_watch.callback = NULL; } return err; @@ -847,11 +849,15 @@ static void connect(struct backend_info *be) xenvif_carrier_on(be->vif); unregister_hotplug_status_watch(be); - err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, - hotplug_status_changed, - "%s/%s", dev->nodename, "hotplug-status"); - if (!err) + if (xenbus_exists(XBT_NIL, dev->nodename, "hotplug-status")) { + err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, + NULL, hotplug_status_changed, + "%s/%s", dev->nodename, + "hotplug-status"); + if (err) + goto err; be->have_hotplug_status_watch = 1; + } netif_tx_wake_all_queues(be->vif->dev); |