Commit 313a58e4 authored by Petko Manolov's avatar Petko Manolov Committed by David S. Miller
Browse files

drivers: net: usb: pegasus: remove skb pool 



The socket buffer pool for the receive path is now gone.  It's existence
didn't make much difference (performance-wise) and the code is better off
without the spinlocks protecting it.

Signed-off-by: default avatarPetko Manolov <petkan@nucleusys.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5f5624cf

drivers/net/usb/pegasus.c

+9 −64
Original line number Diff line number Diff line
@@ -575,51 +575,6 @@ static int enable_net_traffic(struct net_device *dev, struct usb_device *usb) 
	return ret;

}



static void fill_skb_pool(pegasus_t *pegasus)

{

	int i;



	for (i = 0; i < RX_SKBS; i++) {

		if (pegasus->rx_pool[i])

			continue;

		pegasus->rx_pool[i] = dev_alloc_skb(PEGASUS_MTU + 2);

		/*

		 ** we give up if the allocation fail. the tasklet will be

		 ** rescheduled again anyway...

		 */

		if (pegasus->rx_pool[i] == NULL)

			return;

		skb_reserve(pegasus->rx_pool[i], 2);

	}

}



static void free_skb_pool(pegasus_t *pegasus)

{

	int i;



	for (i = 0; i < RX_SKBS; i++) {

		if (pegasus->rx_pool[i]) {

			dev_kfree_skb(pegasus->rx_pool[i]);

			pegasus->rx_pool[i] = NULL;

		}

	}

}



static inline struct sk_buff *pull_skb(pegasus_t * pegasus)

{

	int i;

	struct sk_buff *skb;



	for (i = 0; i < RX_SKBS; i++) {

		if (likely(pegasus->rx_pool[i] != NULL)) {

			skb = pegasus->rx_pool[i];

			pegasus->rx_pool[i] = NULL;

			return skb;

		}

	}

	return NULL;

}



static void read_bulk_callback(struct urb *urb)

{

	pegasus_t *pegasus = urb->context;
@@ -704,9 +659,8 @@ static void read_bulk_callback(struct urb *urb) 
	if (pegasus->flags & PEGASUS_UNPLUG)

		return;



	spin_lock(&pegasus->rx_pool_lock);

	pegasus->rx_skb = pull_skb(pegasus);

	spin_unlock(&pegasus->rx_pool_lock);

	pegasus->rx_skb = __netdev_alloc_skb_ip_align(pegasus->net, PEGASUS_MTU,

						      GFP_ATOMIC);



	if (pegasus->rx_skb == NULL)

		goto tl_sched;
@@ -734,24 +688,23 @@ tl_sched: 
static void rx_fixup(unsigned long data)

{

	pegasus_t *pegasus;

	unsigned long flags;

	int status;



	pegasus = (pegasus_t *) data;

	if (pegasus->flags & PEGASUS_UNPLUG)

		return;



	spin_lock_irqsave(&pegasus->rx_pool_lock, flags);

	fill_skb_pool(pegasus);

	if (pegasus->flags & PEGASUS_RX_URB_FAIL)

		if (pegasus->rx_skb)

			goto try_again;

	if (pegasus->rx_skb == NULL)

		pegasus->rx_skb = pull_skb(pegasus);

		pegasus->rx_skb = __netdev_alloc_skb_ip_align(pegasus->net,

							      PEGASUS_MTU,

							      GFP_ATOMIC);

	if (pegasus->rx_skb == NULL) {

		netif_warn(pegasus, rx_err, pegasus->net, "low on memory\n");

		tasklet_schedule(&pegasus->rx_tl);

		goto done;

		return;

	}

	usb_fill_bulk_urb(pegasus->rx_urb, pegasus->usb,

			  usb_rcvbulkpipe(pegasus->usb, 1),
@@ -767,8 +720,6 @@ try_again: 
	} else {

		pegasus->flags &= ~PEGASUS_RX_URB_FAIL;

	}

done:

	spin_unlock_irqrestore(&pegasus->rx_pool_lock, flags);

}



static void write_bulk_callback(struct urb *urb)
@@ -1007,10 +958,9 @@ static int pegasus_open(struct net_device *net) 
	int res;



	if (pegasus->rx_skb == NULL)

		pegasus->rx_skb = pull_skb(pegasus);

	/*

	 ** Note: no point to free the pool.  it is empty :-)

	 */

		pegasus->rx_skb = __netdev_alloc_skb_ip_align(pegasus->net,

							      PEGASUS_MTU,

							      GFP_KERNEL);

	if (!pegasus->rx_skb)

		return -ENOMEM;
@@ -1044,7 +994,6 @@ static int pegasus_open(struct net_device *net) 
		res = -EIO;

		usb_kill_urb(pegasus->rx_urb);

		usb_kill_urb(pegasus->intr_urb);

		free_skb_pool(pegasus);

		goto exit;

	}

	set_carrier(net);
@@ -1364,7 +1313,6 @@ static int pegasus_probe(struct usb_interface *intf, 
	pegasus->mii.mdio_write = mdio_write;

	pegasus->mii.phy_id_mask = 0x1f;

	pegasus->mii.reg_num_mask = 0x1f;

	spin_lock_init(&pegasus->rx_pool_lock);

	pegasus->msg_enable = netif_msg_init(msg_level, NETIF_MSG_DRV

				| NETIF_MSG_PROBE | NETIF_MSG_LINK);
@@ -1376,7 +1324,6 @@ static int pegasus_probe(struct usb_interface *intf, 
		goto out2;

	}

	set_ethernet_addr(pegasus);

	fill_skb_pool(pegasus);

	if (pegasus->features & PEGASUS_II) {

		dev_info(&intf->dev, "setup Pegasus II specific registers\n");

		setup_pegasus_II(pegasus);
@@ -1404,7 +1351,6 @@ static int pegasus_probe(struct usb_interface *intf, 


out3:

	usb_set_intfdata(intf, NULL);

	free_skb_pool(pegasus);

out2:

	free_all_urbs(pegasus);

out1:
@@ -1429,7 +1375,6 @@ static void pegasus_disconnect(struct usb_interface *intf) 
	unregister_netdev(pegasus->net);

	unlink_all_urbs(pegasus);

	free_all_urbs(pegasus);

	free_skb_pool(pegasus);

	if (pegasus->rx_skb != NULL) {

		dev_kfree_skb(pegasus->rx_skb);

		pegasus->rx_skb = NULL;

drivers/net/usb/pegasus.h

+0 −3
Original line number Diff line number Diff line
@@ -13,7 +13,6 @@ 
#define	HAS_HOME_PNA		0x40000000



#define	PEGASUS_MTU		1536

#define	RX_SKBS			4



#define	EPROM_WRITE		0x01

#define	EPROM_READ		0x02
@@ -97,11 +96,9 @@ typedef struct pegasus { 
	struct tasklet_struct	rx_tl;

	struct delayed_work	carrier_check;

	struct urb		*ctrl_urb, *rx_urb, *tx_urb, *intr_urb;

	struct sk_buff		*rx_pool[RX_SKBS];

	struct sk_buff		*rx_skb;

	struct usb_ctrlrequest	dr;

	wait_queue_head_t	ctrl_wait;

	spinlock_t		rx_pool_lock;

	int			chip;

	unsigned char		intr_buff[8];

	__u8			tx_buff[PEGASUS_MTU];

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