Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f0c65567 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'sunvnet-multi-tx-queue' 

Sowmini Varadhan says:

====================
sunvnet: Use multiple Tx queues.

v2: moved tcp fix out of this series per David Miller feedback

The primary objective of this patch-set is to address the suggestion from
  http://marc.info/?l=linux-netdev&m=140790778931563&w=2


With the changes in Patch 2, every vnet_port will get  packets from
a single tx-queue, and flow-control/head-of-line-blocking is
confined to the vnet_ports that share that tx queue (as opposed to
flow-controlling *all* peers).

Patch 1 is an optimization that resets the DATA_READY bit when
we re-enable Rx interrupts.  This optimization lets us exit quickly
from vnet_event_napi() when new data has not triggered an interrupt.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents cd214535 d51bffd1

drivers/net/ethernet/sun/sunvnet.c

+64 −31
Original line number Diff line number Diff line
@@ -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) {

	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];

			if (vnet_tx_dring_avail(dr) <

			    VNET_TX_WAKEUP_THRESH(dr)) {

				wake = 0;

				break;

			}

			netif_tx_wake_queue(txq);

	}

		rcu_read_unlock();

		if (wake)

			netif_wake_queue(dev);

	}

	netif_tx_unlock(dev);

	__netif_tx_unlock(txq);

}



static inline bool port_is_up(struct vnet_port *vnet)
@@ -748,7 +745,7 @@ napi_resume: 
			break;

	}

	if (unlikely(tx_wakeup && err != -ECONNRESET))

		maybe_tx_wakeup(port->vp);

		maybe_tx_wakeup(port);

	return npkts;

}
@@ -760,6 +757,7 @@ static int vnet_poll(struct napi_struct *napi, int budget) 


	if (processed < budget) {

		napi_complete(napi);

		port->rx_event &= ~LDC_EVENT_DATA_READY;

		vio_set_intr(vio->vdev->rx_ino, HV_INTR_ENABLED);

	}

	return processed;
@@ -952,6 +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);
@@ -964,6 +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))
@@ -1007,9 +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");
@@ -1103,9 +1114,9 @@ ldc_start_done: 


	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);
@@ -1138,14 +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;
@@ -1419,6 +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
@@ -1430,7 +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;
@@ -1555,6 +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;
@@ -1623,6 +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);
@@ -1667,6 +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);

drivers/net/ethernet/sun/sunvnet.h

+2 −0
Original line number Diff line number Diff line
@@ -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 */