From d51bffd16d39d7fe8b374a5fdebf16210ca41892 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Thu, 30 Oct 2014 12:46:09 -0400 Subject: [PATCH] sunvnet: Use one Tx queue per vnet_port Use multple Tx netdev queues for sunvnet by supporting a one-to-one mapping between vnet_port and Tx queue. Provide a ndo_select_queue indirection (vnet_select_queue()) which selects the queue based on the peer that would be selected in vnet_start_xmit() Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller --- drivers/net/ethernet/sun/sunvnet.c | 94 ++++++++++++++++++++---------- drivers/net/ethernet/sun/sunvnet.h | 2 + 2 files changed, 65 insertions(+), 31 deletions(-) diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c index 7ada479f9604..e7bb63b2d525 100644 --- a/drivers/net/ethernet/sun/sunvnet.c +++ b/drivers/net/ethernet/sun/sunvnet.c @@ -40,6 +40,8 @@ MODULE_DESCRIPTION("Sun LDOM virtual network driver"); MODULE_LICENSE("GPL"); MODULE_VERSION(DRV_MODULE_VERSION); +#define VNET_MAX_TXQS 16 + /* Heuristic for the number of times to exponentially backoff and * retry sending an LDC trigger when EAGAIN is encountered */ @@ -551,6 +553,8 @@ static int vnet_ack(struct vnet_port *port, void *msgbuf) struct vnet *vp; u32 end; struct vio_net_desc *desc; + struct netdev_queue *txq; + if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA)) return 0; @@ -580,7 +584,8 @@ static int vnet_ack(struct vnet_port *port, void *msgbuf) } netif_tx_unlock(dev); - if (unlikely(netif_queue_stopped(dev) && + txq = netdev_get_tx_queue(dev, port->q_index); + if (unlikely(netif_tx_queue_stopped(txq) && vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr))) return 1; @@ -608,31 +613,23 @@ static int handle_mcast(struct vnet_port *port, void *msgbuf) return 0; } -static void maybe_tx_wakeup(struct vnet *vp) +/* Got back a STOPPED LDC message on port. If the queue is stopped, + * wake it up so that we'll send out another START message at the + * next TX. + */ +static void maybe_tx_wakeup(struct vnet_port *port) { - struct net_device *dev = vp->dev; + struct netdev_queue *txq; - netif_tx_lock(dev); - if (likely(netif_queue_stopped(dev))) { - struct vnet_port *port; - int wake = 1; - - rcu_read_lock(); - list_for_each_entry_rcu(port, &vp->port_list, list) { - struct vio_dring_state *dr; - - dr = &port->vio.drings[VIO_DRIVER_TX_RING]; - if (vnet_tx_dring_avail(dr) < - VNET_TX_WAKEUP_THRESH(dr)) { - wake = 0; - break; - } - } - rcu_read_unlock(); - if (wake) - netif_wake_queue(dev); + txq = netdev_get_tx_queue(port->vp->dev, port->q_index); + __netif_tx_lock(txq, smp_processor_id()); + if (likely(netif_tx_queue_stopped(txq))) { + struct vio_dring_state *dr; + + dr = &port->vio.drings[VIO_DRIVER_TX_RING]; + netif_tx_wake_queue(txq); } - netif_tx_unlock(dev); + __netif_tx_unlock(txq); } static inline bool port_is_up(struct vnet_port *vnet) @@ -748,7 +745,7 @@ static int vnet_event_napi(struct vnet_port *port, int budget) break; } if (unlikely(tx_wakeup && err != -ECONNRESET)) - maybe_tx_wakeup(port->vp); + maybe_tx_wakeup(port); return npkts; } @@ -953,6 +950,16 @@ static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, void **pstart, return skb; } +static u16 +vnet_select_queue(struct net_device *dev, struct sk_buff *skb, + void *accel_priv, select_queue_fallback_t fallback) +{ + struct vnet *vp = netdev_priv(dev); + struct vnet_port *port = __tx_port_find(vp, skb); + + return port->q_index; +} + static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct vnet *vp = netdev_priv(dev); @@ -965,6 +972,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) void *start = NULL; int nlen = 0; unsigned pending = 0; + struct netdev_queue *txq; skb = vnet_skb_shape(skb, &start, &nlen); if (unlikely(!skb)) @@ -1008,9 +1016,11 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) } dr = &port->vio.drings[VIO_DRIVER_TX_RING]; + i = skb_get_queue_mapping(skb); + txq = netdev_get_tx_queue(dev, i); if (unlikely(vnet_tx_dring_avail(dr) < 1)) { - if (!netif_queue_stopped(dev)) { - netif_stop_queue(dev); + if (!netif_tx_queue_stopped(txq)) { + netif_tx_stop_queue(txq); /* This is a hard error, log it. */ netdev_err(dev, "BUG! Tx Ring full when queue awake!\n"); @@ -1104,9 +1114,9 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1); if (unlikely(vnet_tx_dring_avail(dr) < 1)) { - netif_stop_queue(dev); + netif_tx_stop_queue(txq); if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr)) - netif_wake_queue(dev); + netif_tx_wake_queue(txq); } (void)mod_timer(&port->clean_timer, jiffies + VNET_CLEAN_TIMEOUT); @@ -1139,14 +1149,14 @@ static void vnet_tx_timeout(struct net_device *dev) static int vnet_open(struct net_device *dev) { netif_carrier_on(dev); - netif_start_queue(dev); + netif_tx_start_all_queues(dev); return 0; } static int vnet_close(struct net_device *dev) { - netif_stop_queue(dev); + netif_tx_stop_all_queues(dev); netif_carrier_off(dev); return 0; @@ -1420,6 +1430,7 @@ static const struct net_device_ops vnet_ops = { .ndo_tx_timeout = vnet_tx_timeout, .ndo_change_mtu = vnet_change_mtu, .ndo_start_xmit = vnet_start_xmit, + .ndo_select_queue = vnet_select_queue, #ifdef CONFIG_NET_POLL_CONTROLLER .ndo_poll_controller = vnet_poll_controller, #endif @@ -1431,7 +1442,7 @@ static struct vnet *vnet_new(const u64 *local_mac) struct vnet *vp; int err, i; - dev = alloc_etherdev(sizeof(*vp)); + dev = alloc_etherdev_mqs(sizeof(*vp), VNET_MAX_TXQS, 1); if (!dev) return ERR_PTR(-ENOMEM); dev->needed_headroom = VNET_PACKET_SKIP + 8; @@ -1556,6 +1567,25 @@ static void print_version(void) const char *remote_macaddr_prop = "remote-mac-address"; +static void +vnet_port_add_txq(struct vnet_port *port) +{ + struct vnet *vp = port->vp; + int n; + + n = vp->nports++; + n = n & (VNET_MAX_TXQS - 1); + port->q_index = n; + netif_tx_wake_queue(netdev_get_tx_queue(vp->dev, port->q_index)); +} + +static void +vnet_port_rm_txq(struct vnet_port *port) +{ + port->vp->nports--; + netif_tx_stop_queue(netdev_get_tx_queue(port->vp->dev, port->q_index)); +} + static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id) { struct mdesc_handle *hp; @@ -1624,6 +1654,7 @@ static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id) list_add_tail_rcu(&port->list, &vp->port_list); hlist_add_head_rcu(&port->hash, &vp->port_hash[vnet_hashfn(port->raddr)]); + vnet_port_add_txq(port); spin_unlock_irqrestore(&vp->lock, flags); dev_set_drvdata(&vdev->dev, port); @@ -1668,6 +1699,7 @@ static int vnet_port_remove(struct vio_dev *vdev) synchronize_rcu(); del_timer_sync(&port->clean_timer); + vnet_port_rm_txq(port); netif_napi_del(&port->napi); vnet_port_free_tx_bufs(port); vio_ldc_free(&port->vio); diff --git a/drivers/net/ethernet/sun/sunvnet.h b/drivers/net/ethernet/sun/sunvnet.h index c8a862e471dd..cd5d343ea232 100644 --- a/drivers/net/ethernet/sun/sunvnet.h +++ b/drivers/net/ethernet/sun/sunvnet.h @@ -61,6 +61,7 @@ struct vnet_port { u32 napi_stop_idx; bool napi_resume; int rx_event; + u16 q_index; }; static inline struct vnet_port *to_vnet_port(struct vio_driver_state *vio) @@ -102,6 +103,7 @@ struct vnet { struct list_head list; u64 local_mac; + int nports; }; #endif /* _SUNVNET_H */ -- GitLab