forcedeth: fix irq clearing and napi spin lock changes
This patch clears the irqstatus register with the exact same events it
has read from it. Since the read-write operation is not atomic, a new
irqstatus bit could have been set in between these operations and would
then be cleared accidentally.
Secondly, we now don't need any spin lock protection when
scheduling/completing napi poll as the isr will not execute anymore (as
we turn off all interrupts now).
Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c
index 28fc335..514aaf1 100644
--- a/drivers/net/forcedeth.c
+++ b/drivers/net/forcedeth.c
@@ -3464,10 +3464,10 @@
if (!(np->msi_flags & NV_MSI_X_ENABLED)) {
np->events = readl(base + NvRegIrqStatus);
- writel(NVREG_IRQSTAT_MASK, base + NvRegIrqStatus);
+ writel(np->events, base + NvRegIrqStatus);
} else {
np->events = readl(base + NvRegMSIXIrqStatus);
- writel(NVREG_IRQSTAT_MASK, base + NvRegMSIXIrqStatus);
+ writel(np->events, base + NvRegMSIXIrqStatus);
}
dprintk(KERN_DEBUG "%s: irq: %08x\n", dev->name, np->events);
if (!(np->events & np->irqmask))
@@ -3476,15 +3476,12 @@
nv_msi_workaround(np);
#ifdef CONFIG_FORCEDETH_NAPI
- spin_lock(&np->lock);
napi_schedule(&np->napi);
/* Disable furthur irq's
(msix not enabled with napi) */
writel(0, base + NvRegIrqMask);
- spin_unlock(&np->lock);
-
#else
do
{
@@ -3568,10 +3565,10 @@
if (!(np->msi_flags & NV_MSI_X_ENABLED)) {
np->events = readl(base + NvRegIrqStatus);
- writel(NVREG_IRQSTAT_MASK, base + NvRegIrqStatus);
+ writel(np->events, base + NvRegIrqStatus);
} else {
np->events = readl(base + NvRegMSIXIrqStatus);
- writel(NVREG_IRQSTAT_MASK, base + NvRegMSIXIrqStatus);
+ writel(np->events, base + NvRegMSIXIrqStatus);
}
dprintk(KERN_DEBUG "%s: irq: %08x\n", dev->name, np->events);
if (!(np->events & np->irqmask))
@@ -3580,15 +3577,12 @@
nv_msi_workaround(np);
#ifdef CONFIG_FORCEDETH_NAPI
- spin_lock(&np->lock);
napi_schedule(&np->napi);
/* Disable furthur irq's
(msix not enabled with napi) */
writel(0, base + NvRegIrqMask);
- spin_unlock(&np->lock);
-
#else
do
{
@@ -3758,13 +3752,9 @@
if (rx_work < budget) {
/* re-enable interrupts
(msix not enabled in napi) */
- spin_lock_irqsave(&np->lock, flags);
-
__napi_complete(napi);
writel(np->irqmask, base + NvRegIrqMask);
-
- spin_unlock_irqrestore(&np->lock, flags);
}
return rx_work;
}