[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/arm/ep93xx_eth.c b/drivers/net/arm/ep93xx_eth.c
index f6ece1d..7f016f3 100644
--- a/drivers/net/arm/ep93xx_eth.c
+++ b/drivers/net/arm/ep93xx_eth.c
@@ -169,6 +169,9 @@
spinlock_t tx_pending_lock;
unsigned int tx_pending;
+ struct net_device *dev;
+ struct napi_struct napi;
+
struct net_device_stats stats;
struct mii_if_info mii;
@@ -190,15 +193,11 @@
return &(ep->stats);
}
-static int ep93xx_rx(struct net_device *dev, int *budget)
+static int ep93xx_rx(struct net_device *dev, int processed, int budget)
{
struct ep93xx_priv *ep = netdev_priv(dev);
- int rx_done;
- int processed;
- rx_done = 0;
- processed = 0;
- while (*budget > 0) {
+ while (processed < budget) {
int entry;
struct ep93xx_rstat *rstat;
u32 rstat0;
@@ -211,10 +210,8 @@
rstat0 = rstat->rstat0;
rstat1 = rstat->rstat1;
- if (!(rstat0 & RSTAT0_RFP) || !(rstat1 & RSTAT1_RFP)) {
- rx_done = 1;
+ if (!(rstat0 & RSTAT0_RFP) || !(rstat1 & RSTAT1_RFP))
break;
- }
rstat->rstat0 = 0;
rstat->rstat1 = 0;
@@ -275,8 +272,6 @@
err:
ep->rx_pointer = (entry + 1) & (RX_QUEUE_ENTRIES - 1);
processed++;
- dev->quota--;
- (*budget)--;
}
if (processed) {
@@ -284,7 +279,7 @@
wrw(ep, REG_RXSTSENQ, processed);
}
- return !rx_done;
+ return processed;
}
static int ep93xx_have_more_rx(struct ep93xx_priv *ep)
@@ -293,36 +288,32 @@
return !!((rstat->rstat0 & RSTAT0_RFP) && (rstat->rstat1 & RSTAT1_RFP));
}
-static int ep93xx_poll(struct net_device *dev, int *budget)
+static int ep93xx_poll(struct napi_struct *napi, int budget)
{
- struct ep93xx_priv *ep = netdev_priv(dev);
-
- /*
- * @@@ Have to stop polling if device is downed while we
- * are polling.
- */
+ struct ep93xx_priv *ep = container_of(napi, struct ep93xx_priv, napi);
+ struct net_device *dev = ep->dev;
+ int rx = 0;
poll_some_more:
- if (ep93xx_rx(dev, budget))
- return 1;
+ rx = ep93xx_rx(dev, rx, budget);
+ if (rx < budget) {
+ int more = 0;
- netif_rx_complete(dev);
-
- spin_lock_irq(&ep->rx_lock);
- wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
- if (ep93xx_have_more_rx(ep)) {
- wrl(ep, REG_INTEN, REG_INTEN_TX);
- wrl(ep, REG_INTSTSP, REG_INTSTS_RX);
+ spin_lock_irq(&ep->rx_lock);
+ __netif_rx_complete(dev, napi);
+ wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
+ if (ep93xx_have_more_rx(ep)) {
+ wrl(ep, REG_INTEN, REG_INTEN_TX);
+ wrl(ep, REG_INTSTSP, REG_INTSTS_RX);
+ more = 1;
+ }
spin_unlock_irq(&ep->rx_lock);
- if (netif_rx_reschedule(dev, 0))
+ if (more && netif_rx_reschedule(dev, napi))
goto poll_some_more;
-
- return 0;
}
- spin_unlock_irq(&ep->rx_lock);
- return 0;
+ return rx;
}
static int ep93xx_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -426,9 +417,9 @@
if (status & REG_INTSTS_RX) {
spin_lock(&ep->rx_lock);
- if (likely(__netif_rx_schedule_prep(dev))) {
+ if (likely(__netif_rx_schedule_prep(dev, &ep->napi))) {
wrl(ep, REG_INTEN, REG_INTEN_TX);
- __netif_rx_schedule(dev);
+ __netif_rx_schedule(dev, &ep->napi);
}
spin_unlock(&ep->rx_lock);
}
@@ -648,7 +639,10 @@
dev->dev_addr[4], dev->dev_addr[5]);
}
+ napi_enable(&ep->napi);
+
if (ep93xx_start_hw(dev)) {
+ napi_disable(&ep->napi);
ep93xx_free_buffers(ep);
return -EIO;
}
@@ -662,6 +656,7 @@
err = request_irq(ep->irq, ep93xx_irq, IRQF_SHARED, dev->name, dev);
if (err) {
+ napi_disable(&ep->napi);
ep93xx_stop_hw(dev);
ep93xx_free_buffers(ep);
return err;
@@ -678,6 +673,7 @@
{
struct ep93xx_priv *ep = netdev_priv(dev);
+ napi_disable(&ep->napi);
netif_stop_queue(dev);
wrl(ep, REG_GIINTMSK, 0);
@@ -788,14 +784,12 @@
dev->get_stats = ep93xx_get_stats;
dev->ethtool_ops = &ep93xx_ethtool_ops;
- dev->poll = ep93xx_poll;
dev->hard_start_xmit = ep93xx_xmit;
dev->open = ep93xx_open;
dev->stop = ep93xx_close;
dev->do_ioctl = ep93xx_ioctl;
dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
- dev->weight = 64;
return dev;
}
@@ -847,6 +841,8 @@
goto err_out;
}
ep = netdev_priv(dev);
+ ep->dev = dev;
+ netif_napi_add(dev, &ep->napi, ep93xx_poll, 64);
platform_set_drvdata(pdev, dev);