From 4798248e4e023170e937a65a1d30fcc52496dd42 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 22 Aug 2014 16:21:53 -0700 Subject: [PATCH 1/3] net: Add ops->ndo_xmit_flush() Signed-off-by: David S. Miller --- drivers/net/wan/dlci.c | 2 +- drivers/usb/gadget/function/f_ncm.c | 2 +- include/linux/netdevice.h | 35 +++++++++++++++++++++++++++++ net/atm/mpc.c | 2 +- net/core/dev.c | 5 ++--- net/core/netpoll.c | 3 +-- net/core/pktgen.c | 4 +--- net/packet/af_packet.c | 3 +-- net/sched/sch_teql.c | 3 +-- 9 files changed, 44 insertions(+), 15 deletions(-) diff --git a/drivers/net/wan/dlci.c b/drivers/net/wan/dlci.c index 43c9960dce1c..81b22a180aad 100644 --- a/drivers/net/wan/dlci.c +++ b/drivers/net/wan/dlci.c @@ -193,7 +193,7 @@ static netdev_tx_t dlci_transmit(struct sk_buff *skb, struct net_device *dev) struct dlci_local *dlp = netdev_priv(dev); if (skb) - dlp->slave->netdev_ops->ndo_start_xmit(skb, dlp->slave); + netdev_start_xmit(skb, dlp->slave); return NETDEV_TX_OK; } diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c index bcdc882cd415..cb5d646db6a7 100644 --- a/drivers/usb/gadget/function/f_ncm.c +++ b/drivers/usb/gadget/function/f_ncm.c @@ -1101,7 +1101,7 @@ static void ncm_tx_tasklet(unsigned long data) /* Only send if data is available. */ if (ncm->skb_tx_data) { ncm->timer_force_tx = true; - ncm->netdev->netdev_ops->ndo_start_xmit(NULL, ncm->netdev); + netdev_start_xmit(NULL, ncm->netdev); ncm->timer_force_tx = false; } } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index eb73444e1bd0..220c50984688 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -782,6 +782,19 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev, * (can also return NETDEV_TX_LOCKED iff NETIF_F_LLTX) * Required can not be NULL. * + * void (*ndo_xmit_flush)(struct net_device *dev, u16 queue); + * A driver implements this function when it wishes to support + * deferred TX queue flushing. The idea is that the expensive + * operation to trigger TX queue processing can be done after + * N calls to ndo_start_xmit rather than being done every single + * time. In this regime ndo_start_xmit will be called one or more + * times, and then a final ndo_xmit_flush call will be made to + * have the driver tell the device about the new pending TX queue + * entries. The kernel keeps track of which queues need flushing + * by monitoring skb->queue_mapping of the packets it submits to + * ndo_start_xmit. This is the queue value that will be passed + * to ndo_xmit_flush. + * * u16 (*ndo_select_queue)(struct net_device *dev, struct sk_buff *skb, * void *accel_priv, select_queue_fallback_t fallback); * Called to decide which queue to when device supports multiple @@ -1005,6 +1018,7 @@ struct net_device_ops { int (*ndo_stop)(struct net_device *dev); netdev_tx_t (*ndo_start_xmit) (struct sk_buff *skb, struct net_device *dev); + void (*ndo_xmit_flush)(struct net_device *dev, u16 queue); u16 (*ndo_select_queue)(struct net_device *dev, struct sk_buff *skb, void *accel_priv, @@ -3430,6 +3444,27 @@ int __init dev_proc_init(void); #define dev_proc_init() 0 #endif +static inline netdev_tx_t __netdev_start_xmit(const struct net_device_ops *ops, + struct sk_buff *skb, struct net_device *dev) +{ + netdev_tx_t ret; + u16 q; + + q = skb->queue_mapping; + ret = ops->ndo_start_xmit(skb, dev); + if (dev_xmit_complete(ret) && ops->ndo_xmit_flush) + ops->ndo_xmit_flush(dev, q); + + return ret; +} + +static inline netdev_tx_t netdev_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + const struct net_device_ops *ops = dev->netdev_ops; + + return __netdev_start_xmit(ops, skb, dev); +} + int netdev_class_create_file_ns(struct class_attribute *class_attr, const void *ns); void netdev_class_remove_file_ns(struct class_attribute *class_attr, diff --git a/net/atm/mpc.c b/net/atm/mpc.c index e8e0e7a8a23d..d662da161e5a 100644 --- a/net/atm/mpc.c +++ b/net/atm/mpc.c @@ -599,7 +599,7 @@ static netdev_tx_t mpc_send_packet(struct sk_buff *skb, } non_ip: - return mpc->old_ops->ndo_start_xmit(skb, dev); + return __netdev_start_xmit(mpc->old_ops, skb, dev); } static int atm_mpoa_vcc_attach(struct atm_vcc *vcc, void __user *arg) diff --git a/net/core/dev.c b/net/core/dev.c index b6a718ec11c1..26d296c2447c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2602,7 +2602,6 @@ EXPORT_SYMBOL(netif_skb_features); int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq) { - const struct net_device_ops *ops = dev->netdev_ops; int rc = NETDEV_TX_OK; unsigned int skb_len; @@ -2667,7 +2666,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, skb_len = skb->len; trace_net_dev_start_xmit(skb, dev); - rc = ops->ndo_start_xmit(skb, dev); + rc = netdev_start_xmit(skb, dev); trace_net_dev_xmit(skb, rc, dev, skb_len); if (rc == NETDEV_TX_OK) txq_trans_update(txq); @@ -2686,7 +2685,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, skb_len = nskb->len; trace_net_dev_start_xmit(nskb, dev); - rc = ops->ndo_start_xmit(nskb, dev); + rc = netdev_start_xmit(nskb, dev); trace_net_dev_xmit(nskb, rc, dev, skb_len); if (unlikely(rc != NETDEV_TX_OK)) { if (rc & ~NETDEV_TX_MASK) diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 907fb5e36c02..a5ad06828d67 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -72,7 +72,6 @@ module_param(carrier_timeout, uint, 0644); static int netpoll_start_xmit(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq) { - const struct net_device_ops *ops = dev->netdev_ops; int status = NETDEV_TX_OK; netdev_features_t features; @@ -92,7 +91,7 @@ static int netpoll_start_xmit(struct sk_buff *skb, struct net_device *dev, skb->vlan_tci = 0; } - status = ops->ndo_start_xmit(skb, dev); + status = netdev_start_xmit(skb, dev); if (status == NETDEV_TX_OK) txq_trans_update(txq); diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 8b849ddfef2e..83e2b4b19eb7 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3285,8 +3285,6 @@ static void pktgen_wait_for_skb(struct pktgen_dev *pkt_dev) static void pktgen_xmit(struct pktgen_dev *pkt_dev) { struct net_device *odev = pkt_dev->odev; - netdev_tx_t (*xmit)(struct sk_buff *, struct net_device *) - = odev->netdev_ops->ndo_start_xmit; struct netdev_queue *txq; u16 queue_map; int ret; @@ -3339,7 +3337,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) goto unlock; } atomic_inc(&(pkt_dev->skb->users)); - ret = (*xmit)(pkt_dev->skb, odev); + ret = netdev_start_xmit(pkt_dev->skb, odev); switch (ret) { case NETDEV_TX_OK: diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 93896d2092f6..0dfa990d4eaa 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -240,7 +240,6 @@ static void __fanout_link(struct sock *sk, struct packet_sock *po); static int packet_direct_xmit(struct sk_buff *skb) { struct net_device *dev = skb->dev; - const struct net_device_ops *ops = dev->netdev_ops; netdev_features_t features; struct netdev_queue *txq; int ret = NETDEV_TX_BUSY; @@ -262,7 +261,7 @@ static int packet_direct_xmit(struct sk_buff *skb) HARD_TX_LOCK(dev, txq, smp_processor_id()); if (!netif_xmit_frozen_or_drv_stopped(txq)) { - ret = ops->ndo_start_xmit(skb, dev); + ret = netdev_start_xmit(skb, dev); if (ret == NETDEV_TX_OK) txq_trans_update(txq); } diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c index bd33793b527e..64cd93ca8104 100644 --- a/net/sched/sch_teql.c +++ b/net/sched/sch_teql.c @@ -301,7 +301,6 @@ static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev) do { struct net_device *slave = qdisc_dev(q); struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0); - const struct net_device_ops *slave_ops = slave->netdev_ops; if (slave_txq->qdisc_sleeping != q) continue; @@ -317,7 +316,7 @@ static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev) unsigned int length = qdisc_pkt_len(skb); if (!netif_xmit_frozen_or_stopped(slave_txq) && - slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) { + netdev_start_xmit(skb, slave) == NETDEV_TX_OK) { txq_trans_update(slave_txq); __netif_tx_unlock(slave_txq); master->slaves = NEXT_SLAVE(q); From c1ebf46c1f72fe542853fc00f059a7d15259379d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 22 Aug 2014 17:24:49 -0700 Subject: [PATCH 2/3] igb: Support netdev_ops->ndo_xmit_flush() Signed-off-by: David S. Miller --- drivers/net/ethernet/intel/igb/igb_main.c | 35 ++++++++++++++++------- 1 file changed, 24 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index cb14bbdfb056..b9c020a05fb8 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -136,6 +136,7 @@ static void igb_update_phy_info(unsigned long); static void igb_watchdog(unsigned long); static void igb_watchdog_task(struct work_struct *); static netdev_tx_t igb_xmit_frame(struct sk_buff *skb, struct net_device *); +static void igb_xmit_flush(struct net_device *netdev, u16 queue); static struct rtnl_link_stats64 *igb_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats); static int igb_change_mtu(struct net_device *, int); @@ -2075,6 +2076,7 @@ static const struct net_device_ops igb_netdev_ops = { .ndo_open = igb_open, .ndo_stop = igb_close, .ndo_start_xmit = igb_xmit_frame, + .ndo_xmit_flush = igb_xmit_flush, .ndo_get_stats64 = igb_get_stats64, .ndo_set_rx_mode = igb_set_rx_mode, .ndo_set_mac_address = igb_set_mac, @@ -4915,13 +4917,6 @@ static void igb_tx_map(struct igb_ring *tx_ring, tx_ring->next_to_use = i; - writel(i, tx_ring->tail); - - /* we need this if more than one processor can write to our tail - * at a time, it synchronizes IO on IA64/Altix systems - */ - mmiowb(); - return; dma_error: @@ -5057,17 +5052,20 @@ netdev_tx_t igb_xmit_frame_ring(struct sk_buff *skb, return NETDEV_TX_OK; } -static inline struct igb_ring *igb_tx_queue_mapping(struct igb_adapter *adapter, - struct sk_buff *skb) +static struct igb_ring *__igb_tx_queue_mapping(struct igb_adapter *adapter, unsigned int r_idx) { - unsigned int r_idx = skb->queue_mapping; - if (r_idx >= adapter->num_tx_queues) r_idx = r_idx % adapter->num_tx_queues; return adapter->tx_ring[r_idx]; } +static inline struct igb_ring *igb_tx_queue_mapping(struct igb_adapter *adapter, + struct sk_buff *skb) +{ + return __igb_tx_queue_mapping(adapter, skb->queue_mapping); +} + static netdev_tx_t igb_xmit_frame(struct sk_buff *skb, struct net_device *netdev) { @@ -5096,6 +5094,21 @@ static netdev_tx_t igb_xmit_frame(struct sk_buff *skb, return igb_xmit_frame_ring(skb, igb_tx_queue_mapping(adapter, skb)); } +static void igb_xmit_flush(struct net_device *netdev, u16 queue) +{ + struct igb_adapter *adapter = netdev_priv(netdev); + struct igb_ring *tx_ring; + + tx_ring = __igb_tx_queue_mapping(adapter, queue); + + writel(tx_ring->next_to_use, tx_ring->tail); + + /* we need this if more than one processor can write to our tail + * at a time, it synchronizes IO on IA64/Altix systems + */ + mmiowb(); +} + /** * igb_tx_timeout - Respond to a Tx Hang * @netdev: network interface device structure From c223a078cbe0a87d470b08db7c83c7053931ae63 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sat, 23 Aug 2014 13:18:10 -0700 Subject: [PATCH 3/3] virtio_net: Support netdev_ops->ndo_xmit_flush() Signed-off-by: David S. Miller --- drivers/net/virtio_net.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 59caa06f34a6..62421086d3e6 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -934,7 +934,6 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) dev_kfree_skb_any(skb); return NETDEV_TX_OK; } - virtqueue_kick(sq->vq); /* Don't wait up for transmitted skbs to be freed. */ skb_orphan(skb); @@ -957,6 +956,14 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; } +static void xmit_flush(struct net_device *dev, u16 qnum) +{ + struct virtnet_info *vi = netdev_priv(dev); + struct send_queue *sq = &vi->sq[qnum]; + + virtqueue_kick(sq->vq); +} + /* * Send command via the control virtqueue and check status. Commands * supported by the hypervisor, as indicated by feature bits, should @@ -1386,6 +1393,7 @@ static const struct net_device_ops virtnet_netdev = { .ndo_open = virtnet_open, .ndo_stop = virtnet_close, .ndo_start_xmit = start_xmit, + .ndo_xmit_flush = xmit_flush, .ndo_validate_addr = eth_validate_addr, .ndo_set_mac_address = virtnet_set_mac_address, .ndo_set_rx_mode = virtnet_set_rx_mode,