via-velocity: Implement NAPI support
This patch adds NAPI support for VIA velocity. The new velocity_poll
function also pairs tx/rx handling twice which improves perforamance on
some workloads (e.g., netperf UDP_STREAM) significantly (that part is
from the VIA driver).
Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c
index 7c362b2..47b2882 100644
--- a/drivers/net/via-velocity.c
+++ b/drivers/net/via-velocity.c
@@ -354,12 +354,6 @@
*/
VELOCITY_PARAM(wol_opts, "Wake On Lan options");
-#define INT_WORKS_DEF 20
-#define INT_WORKS_MIN 10
-#define INT_WORKS_MAX 64
-
-VELOCITY_PARAM(int_works, "Number of packets per interrupt services");
-
static int rx_copybreak = 200;
module_param(rx_copybreak, int, 0644);
MODULE_PARM_DESC(rx_copybreak, "Copy breakpoint for copy-only-tiny-frames");
@@ -503,7 +497,6 @@
velocity_set_bool_opt(&opts->flags, ValPktLen[index], VAL_PKT_LEN_DEF, VELOCITY_FLAGS_VAL_PKT_LEN, "ValPktLen", devname);
velocity_set_int_opt((int *) &opts->spd_dpx, speed_duplex[index], MED_LNK_MIN, MED_LNK_MAX, MED_LNK_DEF, "Media link mode", devname);
velocity_set_int_opt((int *) &opts->wol_opts, wol_opts[index], WOL_OPT_MIN, WOL_OPT_MAX, WOL_OPT_DEF, "Wake On Lan options", devname);
- velocity_set_int_opt((int *) &opts->int_works, int_works[index], INT_WORKS_MIN, INT_WORKS_MAX, INT_WORKS_DEF, "Interrupt service works", devname);
opts->numrx = (opts->numrx & ~3);
}
@@ -2109,13 +2102,14 @@
* any received packets from the receive queue. Hand the ring
* slots back to the adapter for reuse.
*/
-static int velocity_rx_srv(struct velocity_info *vptr, int status)
+static int velocity_rx_srv(struct velocity_info *vptr, int status,
+ int budget_left)
{
struct net_device_stats *stats = &vptr->dev->stats;
int rd_curr = vptr->rx.curr;
int works = 0;
- do {
+ while (works < budget_left) {
struct rx_desc *rd = vptr->rx.ring + rd_curr;
if (!vptr->rx.info[rd_curr].skb)
@@ -2146,7 +2140,8 @@
rd_curr++;
if (rd_curr >= vptr->options.numrx)
rd_curr = 0;
- } while (++works <= 15);
+ works++;
+ }
vptr->rx.curr = rd_curr;
@@ -2157,6 +2152,40 @@
return works;
}
+static int velocity_poll(struct napi_struct *napi, int budget)
+{
+ struct velocity_info *vptr = container_of(napi,
+ struct velocity_info, napi);
+ unsigned int rx_done;
+ u32 isr_status;
+
+ spin_lock(&vptr->lock);
+ isr_status = mac_read_isr(vptr->mac_regs);
+
+ /* Ack the interrupt */
+ mac_write_isr(vptr->mac_regs, isr_status);
+ if (isr_status & (~(ISR_PRXI | ISR_PPRXI | ISR_PTXI | ISR_PPTXI)))
+ velocity_error(vptr, isr_status);
+
+ /*
+ * Do rx and tx twice for performance (taken from the VIA
+ * out-of-tree driver).
+ */
+ rx_done = velocity_rx_srv(vptr, isr_status, budget / 2);
+ velocity_tx_srv(vptr, isr_status);
+ rx_done += velocity_rx_srv(vptr, isr_status, budget - rx_done);
+ velocity_tx_srv(vptr, isr_status);
+
+ spin_unlock(&vptr->lock);
+
+ /* If budget not fully consumed, exit the polling mode */
+ if (rx_done < budget) {
+ napi_complete(napi);
+ mac_enable_int(vptr->mac_regs);
+ }
+
+ return rx_done;
+}
/**
* velocity_intr - interrupt callback
@@ -2173,8 +2202,6 @@
struct net_device *dev = dev_instance;
struct velocity_info *vptr = netdev_priv(dev);
u32 isr_status;
- int max_count = 0;
-
spin_lock(&vptr->lock);
isr_status = mac_read_isr(vptr->mac_regs);
@@ -2185,32 +2212,13 @@
return IRQ_NONE;
}
- mac_disable_int(vptr->mac_regs);
-
- /*
- * Keep processing the ISR until we have completed
- * processing and the isr_status becomes zero
- */
-
- while (isr_status != 0) {
- mac_write_isr(vptr->mac_regs, isr_status);
- if (isr_status & (~(ISR_PRXI | ISR_PPRXI | ISR_PTXI | ISR_PPTXI)))
- velocity_error(vptr, isr_status);
- if (isr_status & (ISR_PRXI | ISR_PPRXI))
- max_count += velocity_rx_srv(vptr, isr_status);
- if (isr_status & (ISR_PTXI | ISR_PPTXI))
- max_count += velocity_tx_srv(vptr, isr_status);
- isr_status = mac_read_isr(vptr->mac_regs);
- if (max_count > vptr->options.int_works) {
- printk(KERN_WARNING "%s: excessive work at interrupt.\n",
- dev->name);
- max_count = 0;
- }
+ if (likely(napi_schedule_prep(&vptr->napi))) {
+ mac_disable_int(vptr->mac_regs);
+ __napi_schedule(&vptr->napi);
}
spin_unlock(&vptr->lock);
- mac_enable_int(vptr->mac_regs);
- return IRQ_HANDLED;
+ return IRQ_HANDLED;
}
/**
@@ -2250,6 +2258,7 @@
mac_enable_int(vptr->mac_regs);
netif_start_queue(dev);
+ napi_enable(&vptr->napi);
vptr->flags |= VELOCITY_FLAGS_OPENED;
out:
return ret;
@@ -2485,6 +2494,7 @@
{
struct velocity_info *vptr = netdev_priv(dev);
+ napi_disable(&vptr->napi);
netif_stop_queue(dev);
velocity_shutdown(vptr);
@@ -2803,6 +2813,7 @@
dev->irq = pdev->irq;
dev->netdev_ops = &velocity_netdev_ops;
dev->ethtool_ops = &velocity_ethtool_ops;
+ netif_napi_add(dev, &vptr->napi, velocity_poll, VELOCITY_NAPI_WEIGHT);
dev->features |= NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_FILTER |
NETIF_F_HW_VLAN_RX;