[NET]: Make NAPI polling independent of struct net_device objects.
Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.
In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.
The signature of the ->poll() call back goes from:
int foo_poll(struct net_device *dev, int *budget)
to
int foo_poll(struct napi_struct *napi, int budget)
The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract). The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.
The napi_struct is to be embedded in the device driver private data
structures.
Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler. Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.
With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.
Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.
[ Ported to current tree and all drivers converted. Integrated
Stephen's follow-on kerneldoc additions, and restored poll_list
handling to the old style to fix mutual exclusion issues. -DaveM ]
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ixp2000/ixpdev.c b/drivers/net/ixp2000/ixpdev.c
index d9ce1ae..6c0dd49 100644
--- a/drivers/net/ixp2000/ixpdev.c
+++ b/drivers/net/ixp2000/ixpdev.c
@@ -74,9 +74,9 @@
}
-static int ixpdev_rx(struct net_device *dev, int *budget)
+static int ixpdev_rx(struct net_device *dev, int processed, int budget)
{
- while (*budget > 0) {
+ while (processed < budget) {
struct ixpdev_rx_desc *desc;
struct sk_buff *skb;
void *buf;
@@ -122,29 +122,34 @@
err:
ixp2000_reg_write(RING_RX_PENDING, _desc);
- dev->quota--;
- (*budget)--;
+ processed++;
}
- return 1;
+ return processed;
}
/* dev always points to nds[0]. */
-static int ixpdev_poll(struct net_device *dev, int *budget)
+static int ixpdev_poll(struct napi_struct *napi, int budget)
{
+ struct ixpdev_priv *ip = container_of(napi, struct ixpdev_priv, napi);
+ struct net_device *dev = ip->dev;
+ int rx;
+
/* @@@ Have to stop polling when nds[0] is administratively
* downed while we are polling. */
+ rx = 0;
do {
ixp2000_reg_write(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0x00ff);
- if (ixpdev_rx(dev, budget))
- return 1;
+ rx = ixpdev_rx(dev, rx, budget);
+ if (rx >= budget)
+ break;
} while (ixp2000_reg_read(IXP2000_IRQ_THD_RAW_STATUS_A_0) & 0x00ff);
- netif_rx_complete(dev);
+ netif_rx_complete(dev, napi);
ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
- return 0;
+ return rx;
}
static void ixpdev_tx_complete(void)
@@ -199,9 +204,12 @@
* Any of the eight receive units signaled RX?
*/
if (status & 0x00ff) {
+ struct net_device *dev = nds[0];
+ struct ixpdev_priv *ip = netdev_priv(dev);
+
ixp2000_reg_wrb(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0x00ff);
- if (likely(__netif_rx_schedule_prep(nds[0]))) {
- __netif_rx_schedule(nds[0]);
+ if (likely(napi_schedule_prep(&ip->napi))) {
+ __netif_rx_schedule(dev, &ip->napi);
} else {
printk(KERN_CRIT "ixp2000: irq while polling!!\n");
}
@@ -232,11 +240,13 @@
struct ixpdev_priv *ip = netdev_priv(dev);
int err;
+ napi_enable(&ip->napi);
if (!nds_open++) {
err = request_irq(IRQ_IXP2000_THDA0, ixpdev_interrupt,
IRQF_SHARED, "ixp2000_eth", nds);
if (err) {
nds_open--;
+ napi_disable(&ip->napi);
return err;
}
@@ -254,6 +264,7 @@
struct ixpdev_priv *ip = netdev_priv(dev);
netif_stop_queue(dev);
+ napi_disable(&ip->napi);
set_port_admin_status(ip->channel, 0);
if (!--nds_open) {
@@ -274,7 +285,6 @@
return NULL;
dev->hard_start_xmit = ixpdev_xmit;
- dev->poll = ixpdev_poll;
dev->open = ixpdev_open;
dev->stop = ixpdev_close;
#ifdef CONFIG_NET_POLL_CONTROLLER
@@ -282,9 +292,10 @@
#endif
dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
- dev->weight = 64;
ip = netdev_priv(dev);
+ ip->dev = dev;
+ netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
ip->channel = channel;
ip->tx_queue_entries = 0;