netxen: napi and irq cleanup
o separate and simpler irq handler for msi interrupts, avoids few checks
than legacy mode.
o avoid redudant tx_has_work() and rx_has_work() checks in interrupt
and napi, which can uncork irq based on racy (lockless) access to tx
and rx ring indices. If we get interrupt, there's sufficient reason to
schedule napi.
o replenish rx ring more often, remove self-imposed threshold rcv_free
that prevents posting rx desc to card. This improves performance in
low memory.
Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Tested-by: Vernon Mauery <mauery@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c
index cd665da..9595520 100644
--- a/drivers/net/netxen/netxen_nic_main.c
+++ b/drivers/net/netxen/netxen_nic_main.c
@@ -63,12 +63,12 @@
static void netxen_tx_timeout(struct net_device *netdev);
static void netxen_tx_timeout_task(struct work_struct *work);
static void netxen_watchdog(unsigned long);
-static int netxen_handle_int(struct netxen_adapter *, struct net_device *);
static int netxen_nic_poll(struct napi_struct *napi, int budget);
#ifdef CONFIG_NET_POLL_CONTROLLER
static void netxen_nic_poll_controller(struct net_device *netdev);
#endif
static irqreturn_t netxen_intr(int irq, void *data);
+static irqreturn_t netxen_msi_intr(int irq, void *data);
int physical_port[] = {0, 1, 2, 3};
@@ -405,7 +405,7 @@
netdev->set_mac_address = netxen_nic_set_mac;
netdev->change_mtu = netxen_nic_change_mtu;
netdev->tx_timeout = netxen_tx_timeout;
- netdev->watchdog_timeo = HZ;
+ netdev->watchdog_timeo = 2*HZ;
netxen_nic_change_mtu(netdev, netdev->mtu);
@@ -823,6 +823,8 @@
struct netxen_adapter *adapter = (struct netxen_adapter *)netdev->priv;
int err = 0;
int ctx, ring;
+ irq_handler_t handler;
+ unsigned long flags = IRQF_SAMPLE_RANDOM;
if (adapter->is_up != NETXEN_ADAPTER_UP_MAGIC) {
err = netxen_init_firmware(adapter);
@@ -846,9 +848,14 @@
netxen_post_rx_buffers(adapter, ctx, ring);
}
adapter->irq = adapter->ahw.pdev->irq;
- err = request_irq(adapter->ahw.pdev->irq, netxen_intr,
- IRQF_SHARED|IRQF_SAMPLE_RANDOM, netdev->name,
- adapter);
+ if (adapter->flags & NETXEN_NIC_MSI_ENABLED)
+ handler = netxen_msi_intr;
+ else {
+ flags |= IRQF_SHARED;
+ handler = netxen_intr;
+ }
+ err = request_irq(adapter->irq, handler,
+ flags, netdev->name, adapter);
if (err) {
printk(KERN_ERR "request_irq failed with: %d\n", err);
netxen_free_hw_resources(adapter);
@@ -857,21 +864,12 @@
adapter->is_up = NETXEN_ADAPTER_UP_MAGIC;
}
- if (!adapter->driver_mismatch)
- mod_timer(&adapter->watchdog_timer, jiffies);
-
- napi_enable(&adapter->napi);
-
- netxen_nic_enable_int(adapter);
-
/* Done here again so that even if phantom sw overwrote it,
* we set it */
if (adapter->init_port
&& adapter->init_port(adapter, adapter->portnum) != 0) {
- del_timer_sync(&adapter->watchdog_timer);
printk(KERN_ERR "%s: Failed to initialize port %d\n",
netxen_nic_driver_name, adapter->portnum);
- napi_disable(&adapter->napi);
return -EIO;
}
if (adapter->macaddr_set)
@@ -884,6 +882,12 @@
adapter->set_mtu(adapter, netdev->mtu);
if (!adapter->driver_mismatch)
+ mod_timer(&adapter->watchdog_timer, jiffies);
+
+ napi_enable(&adapter->napi);
+ netxen_nic_enable_int(adapter);
+
+ if (!adapter->driver_mismatch)
netif_start_queue(netdev);
return 0;
@@ -1196,81 +1200,50 @@
netif_wake_queue(adapter->netdev);
}
-static int
-netxen_handle_int(struct netxen_adapter *adapter, struct net_device *netdev)
+static inline void
+netxen_handle_int(struct netxen_adapter *adapter)
{
- u32 ret = 0;
-
- DPRINTK(INFO, "Entered handle ISR\n");
- adapter->stats.ints++;
-
netxen_nic_disable_int(adapter);
-
- if (netxen_nic_rx_has_work(adapter) || netxen_nic_tx_has_work(adapter)) {
- if (netif_rx_schedule_prep(netdev, &adapter->napi)) {
- /*
- * Interrupts are already disabled.
- */
- __netif_rx_schedule(netdev, &adapter->napi);
- } else {
- static unsigned int intcount = 0;
- if ((++intcount & 0xfff) == 0xfff)
- DPRINTK(KERN_ERR
- "%s: %s interrupt %d while in poll\n",
- netxen_nic_driver_name, netdev->name,
- intcount);
- }
- ret = 1;
- }
-
- if (ret == 0) {
- netxen_nic_enable_int(adapter);
- }
-
- return ret;
+ napi_schedule(&adapter->napi);
}
-/*
- * netxen_intr - Interrupt Handler
- * @irq: interrupt number
- * data points to adapter stucture (which may be handling more than 1 port
- */
irqreturn_t netxen_intr(int irq, void *data)
{
struct netxen_adapter *adapter = data;
- struct net_device *netdev = adapter->netdev;
u32 our_int = 0;
- if (!(adapter->flags & NETXEN_NIC_MSI_ENABLED)) {
- our_int = readl(NETXEN_CRB_NORMALIZE(adapter, CRB_INT_VECTOR));
- /* not our interrupt */
- if ((our_int & (0x80 << adapter->portnum)) == 0)
- return IRQ_NONE;
- }
+ our_int = readl(NETXEN_CRB_NORMALIZE(adapter, CRB_INT_VECTOR));
+ /* not our interrupt */
+ if ((our_int & (0x80 << adapter->portnum)) == 0)
+ return IRQ_NONE;
if (adapter->intr_scheme == INTR_SCHEME_PERPORT) {
/* claim interrupt */
- if (!(adapter->flags & NETXEN_NIC_MSI_ENABLED)) {
- writel(our_int & ~((u32)(0x80 << adapter->portnum)),
+ writel(our_int & ~((u32)(0x80 << adapter->portnum)),
NETXEN_CRB_NORMALIZE(adapter, CRB_INT_VECTOR));
- }
}
- if (netif_running(netdev))
- netxen_handle_int(adapter, netdev);
+ netxen_handle_int(adapter);
return IRQ_HANDLED;
}
+irqreturn_t netxen_msi_intr(int irq, void *data)
+{
+ struct netxen_adapter *adapter = data;
+
+ netxen_handle_int(adapter);
+ return IRQ_HANDLED;
+}
+
static int netxen_nic_poll(struct napi_struct *napi, int budget)
{
struct netxen_adapter *adapter = container_of(napi, struct netxen_adapter, napi);
- struct net_device *netdev = adapter->netdev;
- int done = 1;
+ int tx_complete;
int ctx;
int work_done;
- DPRINTK(INFO, "polling for %d descriptors\n", *budget);
+ tx_complete = netxen_process_cmd_ring(adapter);
work_done = 0;
for (ctx = 0; ctx < MAX_RCV_CTX; ++ctx) {
@@ -1290,16 +1263,8 @@
budget / MAX_RCV_CTX);
}
- if (work_done >= budget)
- done = 0;
-
- if (netxen_process_cmd_ring((unsigned long)adapter) == 0)
- done = 0;
-
- DPRINTK(INFO, "new work_done: %d work_to_do: %d\n",
- work_done, work_to_do);
- if (done) {
- netif_rx_complete(netdev, napi);
+ if ((work_done < budget) && tx_complete) {
+ netif_rx_complete(adapter->netdev, &adapter->napi);
netxen_nic_enable_int(adapter);
}