Skip to content

Commit

Permalink
[PATCH] forcdeth: revised NAPI support
Browse files Browse the repository at this point in the history 
Revised version of the forcedeth NAPI support.
This version is based against netdev-2.6#upstream
(after the MAC patches from Ayaz today).

Can't use nv_disable_hw_interrupts because NAPI only wants to
mask off receive irq's and leave the others alone.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
  • Loading branch information
Stephen Hemminger authored and Jeff Garzik committed Aug 9, 2006
1 parent 5070d34 commit e27cdba
Show file tree
Hide file tree
Showing 2 changed files with 140 additions and 16 deletions.
16 changes: 16 additions & 0 deletions drivers/net/Kconfig
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1411,6 +1411,22 @@ config FORCEDETH
<file:Documentation/networking/net-modules.txt>. The module will be
called forcedeth.

config FORCEDETH_NAPI
bool "Use Rx and Tx Polling (NAPI) (EXPERIMENTAL)"
depends on FORCEDETH && EXPERIMENTAL
help
NAPI is a new driver API designed to reduce CPU and interrupt load
when the driver is receiving lots of packets from the card. It is
still somewhat experimental and thus not yet enabled by default.

If your estimated Rx load is 10kpps or more, or if the card will be
deployed on potentially unfriendly networks (e.g. in a firewall),
then say Y here.

See <file:Documentation/networking/NAPI_HOWTO.txt> for more
information.

If in doubt, say N.

config CS89x0
tristate "CS89x0 support"
Expand Down
140 changes: 124 additions & 16 deletions drivers/net/forcedeth.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -121,6 +121,11 @@
* DEV_NEED_TIMERIRQ will not harm you on sane hardware, only generating a few
* superfluous timer interrupts from the nic.
*/
#ifdef CONFIG_FORCEDETH_NAPI
#define DRIVERNAPI "-NAPI"
#else
#define DRIVERNAPI
#endif
#define FORCEDETH_VERSION "0.57"
#define DRV_NAME "forcedeth"

Expand Down Expand Up @@ -1279,6 +1284,16 @@ static int nv_alloc_rx(struct net_device *dev)
return 0;
}

/* If rx bufs are exhausted called after 50ms to attempt to refresh */
#ifdef CONFIG_FORCEDETH_NAPI
static void nv_do_rx_refill(unsigned long data)
{
struct net_device *dev = (struct net_device *) data;

/* Just reschedule NAPI rx processing */
netif_rx_schedule(dev);
}
#else
static void nv_do_rx_refill(unsigned long data)
{
struct net_device *dev = (struct net_device *) data;
Expand Down Expand Up @@ -1307,6 +1322,7 @@ static void nv_do_rx_refill(unsigned long data)
enable_irq(np->msi_x_entry[NV_MSI_X_VECTOR_RX].vector);
}
}
#endif

static void nv_init_rx(struct net_device *dev)
{
Expand Down Expand Up @@ -1742,13 +1758,14 @@ static int nv_getlen(struct net_device *dev, void *packet, int datalen)
}
}

static void nv_rx_process(struct net_device *dev)
static int nv_rx_process(struct net_device *dev, int limit)
{
struct fe_priv *np = netdev_priv(dev);
u32 flags;
u32 vlanflags = 0;
int count;

for (;;) {
for (count = 0; count < limit; ++count) {
struct sk_buff *skb;
int len;
int i;
Expand Down Expand Up @@ -1882,17 +1899,27 @@ static void nv_rx_process(struct net_device *dev)
skb->protocol = eth_type_trans(skb, dev);
dprintk(KERN_DEBUG "%s: nv_rx_process: packet %d with %d bytes, proto %d accepted.\n",
dev->name, np->cur_rx, len, skb->protocol);
if (np->vlangrp && (vlanflags & NV_RX3_VLAN_TAG_PRESENT)) {
vlan_hwaccel_rx(skb, np->vlangrp, vlanflags & NV_RX3_VLAN_TAG_MASK);
} else {
#ifdef CONFIG_FORCEDETH_NAPI
if (np->vlangrp && (vlanflags & NV_RX3_VLAN_TAG_PRESENT))
vlan_hwaccel_receive_skb(skb, np->vlangrp,
vlanflags & NV_RX3_VLAN_TAG_MASK);
else
netif_receive_skb(skb);
#else
if (np->vlangrp && (vlanflags & NV_RX3_VLAN_TAG_PRESENT))
vlan_hwaccel_rx(skb, np->vlangrp,
vlanflags & NV_RX3_VLAN_TAG_MASK);
else
netif_rx(skb);
}
#endif
dev->last_rx = jiffies;
np->stats.rx_packets++;
np->stats.rx_bytes += len;
next_pkt:
np->cur_rx++;
}

return count;
}

static void set_bufsize(struct net_device *dev)
Expand Down Expand Up @@ -2378,14 +2405,6 @@ static irqreturn_t nv_nic_irq(int foo, void *data, struct pt_regs *regs)
nv_tx_done(dev);
spin_unlock(&np->lock);

nv_rx_process(dev);
if (nv_alloc_rx(dev)) {
spin_lock(&np->lock);
if (!np->in_shutdown)
mod_timer(&np->oom_kick, jiffies + OOM_REFILL);
spin_unlock(&np->lock);
}

if (events & NVREG_IRQ_LINK) {
spin_lock(&np->lock);
nv_link_irq(dev);
Expand All @@ -2405,6 +2424,29 @@ static irqreturn_t nv_nic_irq(int foo, void *data, struct pt_regs *regs)
printk(KERN_DEBUG "%s: received irq with unknown events 0x%x. Please report\n",
dev->name, events);
}
#ifdef CONFIG_FORCEDETH_NAPI
if (events & NVREG_IRQ_RX_ALL) {
netif_rx_schedule(dev);

/* Disable furthur receive irq's */
spin_lock(&np->lock);
np->irqmask &= ~NVREG_IRQ_RX_ALL;

if (np->msi_flags & NV_MSI_X_ENABLED)
writel(NVREG_IRQ_RX_ALL, base + NvRegIrqMask);
else
writel(np->irqmask, base + NvRegIrqMask);
spin_unlock(&np->lock);
}
#else
nv_rx_process(dev, dev->weight);
if (nv_alloc_rx(dev)) {
spin_lock(&np->lock);
if (!np->in_shutdown)
mod_timer(&np->oom_kick, jiffies + OOM_REFILL);
spin_unlock(&np->lock);
}
#endif
if (i > max_interrupt_work) {
spin_lock(&np->lock);
/* disable interrupts on the nic */
Expand Down Expand Up @@ -2476,6 +2518,63 @@ static irqreturn_t nv_nic_irq_tx(int foo, void *data, struct pt_regs *regs)
return IRQ_RETVAL(i);
}

#ifdef CONFIG_FORCEDETH_NAPI
static int nv_napi_poll(struct net_device *dev, int *budget)
{
int pkts, limit = min(*budget, dev->quota);
struct fe_priv *np = netdev_priv(dev);
u8 __iomem *base = get_hwbase(dev);

pkts = nv_rx_process(dev, limit);

if (nv_alloc_rx(dev)) {
spin_lock_irq(&np->lock);
if (!np->in_shutdown)
mod_timer(&np->oom_kick, jiffies + OOM_REFILL);
spin_unlock_irq(&np->lock);
}

if (pkts < limit) {
/* all done, no more packets present */
netif_rx_complete(dev);

/* re-enable receive interrupts */
spin_lock_irq(&np->lock);
np->irqmask |= NVREG_IRQ_RX_ALL;
if (np->msi_flags & NV_MSI_X_ENABLED)
writel(NVREG_IRQ_RX_ALL, base + NvRegIrqMask);
else
writel(np->irqmask, base + NvRegIrqMask);
spin_unlock_irq(&np->lock);
return 0;
} else {
/* used up our quantum, so reschedule */
dev->quota -= pkts;
*budget -= pkts;
return 1;
}
}
#endif

#ifdef CONFIG_FORCEDETH_NAPI
static irqreturn_t nv_nic_irq_rx(int foo, void *data, struct pt_regs *regs)
{
struct net_device *dev = (struct net_device *) data;
u8 __iomem *base = get_hwbase(dev);
u32 events;

events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQ_RX_ALL;
writel(NVREG_IRQ_RX_ALL, base + NvRegMSIXIrqStatus);

if (events) {
netif_rx_schedule(dev);
/* disable receive interrupts on the nic */
writel(NVREG_IRQ_RX_ALL, base + NvRegIrqMask);
pci_push(base);
}
return IRQ_HANDLED;
}
#else
static irqreturn_t nv_nic_irq_rx(int foo, void *data, struct pt_regs *regs)
{
struct net_device *dev = (struct net_device *) data;
Expand All @@ -2494,7 +2593,7 @@ static irqreturn_t nv_nic_irq_rx(int foo, void *data, struct pt_regs *regs)
if (!(events & np->irqmask))
break;

nv_rx_process(dev);
nv_rx_process(dev, dev->weight);
if (nv_alloc_rx(dev)) {
spin_lock_irq(&np->lock);
if (!np->in_shutdown)
Expand All @@ -2516,12 +2615,12 @@ static irqreturn_t nv_nic_irq_rx(int foo, void *data, struct pt_regs *regs)
spin_unlock_irq(&np->lock);
break;
}

}
dprintk(KERN_DEBUG "%s: nv_nic_irq_rx completed\n", dev->name);

return IRQ_RETVAL(i);
}
#endif

static irqreturn_t nv_nic_irq_other(int foo, void *data, struct pt_regs *regs)
{
Expand Down Expand Up @@ -3755,6 +3854,7 @@ static void nv_self_test(struct net_device *dev, struct ethtool_test *test, u64
if (test->flags & ETH_TEST_FL_OFFLINE) {
if (netif_running(dev)) {
netif_stop_queue(dev);
netif_poll_disable(dev);
netif_tx_lock_bh(dev);
spin_lock_irq(&np->lock);
nv_disable_hw_interrupts(dev, np->irqmask);
Expand Down Expand Up @@ -3813,6 +3913,7 @@ static void nv_self_test(struct net_device *dev, struct ethtool_test *test, u64
nv_start_rx(dev);
nv_start_tx(dev);
netif_start_queue(dev);
netif_poll_enable(dev);
nv_enable_hw_interrupts(dev, np->irqmask);
}
}
Expand Down Expand Up @@ -4016,6 +4117,8 @@ static int nv_open(struct net_device *dev)
nv_start_rx(dev);
nv_start_tx(dev);
netif_start_queue(dev);
netif_poll_enable(dev);

if (ret) {
netif_carrier_on(dev);
} else {
Expand Down Expand Up @@ -4045,6 +4148,7 @@ static int nv_close(struct net_device *dev)
spin_lock_irq(&np->lock);
np->in_shutdown = 1;
spin_unlock_irq(&np->lock);
netif_poll_disable(dev);
synchronize_irq(dev->irq);

del_timer_sync(&np->oom_kick);
Expand Down Expand Up @@ -4259,6 +4363,10 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i
dev->set_multicast_list = nv_set_multicast;
#ifdef CONFIG_NET_POLL_CONTROLLER
dev->poll_controller = nv_poll_controller;
#endif
dev->weight = 64;
#ifdef CONFIG_FORCEDETH_NAPI
dev->poll = nv_napi_poll;
#endif
SET_ETHTOOL_OPS(dev, &ops);
dev->tx_timeout = nv_tx_timeout;
Expand Down

0 comments on commit e27cdba

Please sign in to comment.