[patch 02/12] sky2: reduce impact of watchdog timer

Greg KH
2007-10-08T18:08:42Z

[-- Attachment #1: sky2-hw-watchdog.patch --]
[-- Type: text/plain, Size: 4220 bytes --]

From: Stephen Hemminger <shemminger@linux-foundation.org>

This is the 2.6.22 version of a regression fix that is already
in 2.6.23. Change the watchdog timer form 10 per second all the time,
to 1 per second and only if interface is up.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/net/sky2.c | 45 ++++++++++++++++++---------------------------
drivers/net/sky2.h | 2 +-
2 files changed, 19 insertions(+), 28 deletions(-)

--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -96,10 +96,6 @@ static int disable_msi = 0;
module_param(disable_msi, int, 0);
MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");

-static int idle_timeout = 100;
-module_param(idle_timeout, int, 0);
-MODULE_PARM_DESC(idle_timeout, "Watchdog timer for lost interrupts (ms)");
-
static const struct pci_device_id sky2_id_table[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_SYSKONNECT, 0x9000) }, /* SK-9Sxx */
{ PCI_DEVICE(PCI_VENDOR_ID_SYSKONNECT, 0x9E00) }, /* SK-9Exx */
@@ -1693,6 +1689,8 @@ static void sky2_link_up(struct sky2_por

netif_carrier_on(sky2->netdev);

+ mod_timer(&hw->watchdog_timer, jiffies + 1);
+
/* Turn on link LED */
sky2_write8(hw, SK_REG(port, LNK_LED_REG),
LINKLED_ON | LINKLED_BLINK_OFF | LINKLED_LINKSYNC_OFF);
@@ -2384,25 +2382,25 @@ static void sky2_le_error(struct sky2_hw
sky2_write32(hw, Q_ADDR(q, Q_CSR), BMU_CLR_IRQ_CHK);
}

-/* If idle then force a fake soft NAPI poll once a second
- * to work around cases where sharing an edge triggered interrupt.
- */
-static inline void sky2_idle_start(struct sky2_hw *hw)
-{
- if (idle_timeout > 0)
- mod_timer(&hw->idle_timer,
- jiffies + msecs_to_jiffies(idle_timeout));
-}
-
-static void sky2_idle(unsigned long arg)
+/* Force a fake soft NAPI poll to handle lost IRQ's */
+static void sky2_watchdog(unsigned long arg)
{
struct sky2_hw *hw = (struct sky2_hw *) arg;
struct net_device *dev = hw->dev[0];
+ int i, active = 0;

if (__netif_rx_schedule_prep(dev))
__netif_rx_schedule(dev);

- mod_timer(&hw->idle_timer, jiffies + msecs_to_jiffies(idle_timeout));
+ for (i = 0; i < hw->ports; i++) {
+ dev = hw->dev[i];
+ if (!netif_running(dev))
+ continue;
+ ++active;
+ }
+
+ if (active)
+ mod_timer(&hw->watchdog_timer, round_jiffies(jiffies + HZ));
}

/* Hardware/software error handling */
@@ -2692,8 +2690,6 @@ static void sky2_restart(struct work_str

dev_dbg(&hw->pdev->dev, "restarting\n");

- del_timer_sync(&hw->idle_timer);
-
rtnl_lock();
sky2_write32(hw, B0_IMSK, 0);
sky2_read32(hw, B0_IMSK);
@@ -2722,8 +2718,6 @@ static void sky2_restart(struct work_str
}
}

- sky2_idle_start(hw);
-
rtnl_unlock();
}

@@ -3713,11 +3707,9 @@ static int __devinit sky2_probe(struct p
sky2_show_addr(dev1);
}

- setup_timer(&hw->idle_timer, sky2_idle, (unsigned long) hw);
+ setup_timer(&hw->watchdog_timer, sky2_watchdog, (unsigned long) hw);
INIT_WORK(&hw->restart_work, sky2_restart);

- sky2_idle_start(hw);
-
pci_set_drvdata(pdev, hw);

return 0;
@@ -3752,7 +3744,7 @@ static void __devexit sky2_remove(struct
if (!hw)
return;

- del_timer_sync(&hw->idle_timer);
+ del_timer_sync(&hw->watchdog_timer);

flush_scheduled_work();

@@ -3796,7 +3788,7 @@ static int sky2_suspend(struct pci_dev *
if (!hw)
return 0;

- del_timer_sync(&hw->idle_timer);
+ del_timer_sync(&hw->watchdog_timer);
netif_poll_disable(hw->dev[0]);

for (i = 0; i < hw->ports; i++) {
@@ -3862,7 +3854,7 @@ static int sky2_resume(struct pci_dev *p
}

netif_poll_enable(hw->dev[0]);
- sky2_idle_start(hw);
+
return 0;
out:
dev_err(&pdev->dev, "resume failed (%d)\n", err);
@@ -3879,7 +3871,6 @@ static void sky2_shutdown(struct pci_dev
if (!hw)
return;

- del_timer_sync(&hw->idle_timer);
netif_poll_disable(hw->dev[0]);

for (i = 0; i < hw->ports; i++) {
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -1921,7 +1921,7 @@ struct sky2_hw {
u32 st_idx;
dma_addr_t st_dma;

- struct timer_list idle_timer;
+ struct timer_list watchdog_timer;
struct work_struct restart_work;
int msi;
wait_queue_head_t msi_wait;

--