skge: NAPI/irq race fix
Fix a race in the receive NAPI, irq handling. The interrupt clear and the
start need to be separated. Otherwise there is a window between the last
frame received and the NAPI done level handling.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
diff --git a/drivers/net/skge.c b/drivers/net/skge.c
index 67fb19b..869c7cf 100644
--- a/drivers/net/skge.c
+++ b/drivers/net/skge.c
@@ -2678,8 +2678,7 @@
/* restart receiver */
wmb();
- skge_write8(hw, Q_ADDR(rxqaddr[skge->port], Q_CSR),
- CSR_START | CSR_IRQ_CL_F);
+ skge_write8(hw, Q_ADDR(rxqaddr[skge->port], Q_CSR), CSR_START);
*budget -= work_done;
dev->quota -= work_done;
@@ -2856,14 +2855,6 @@
local_irq_enable();
}
-static inline void skge_wakeup(struct net_device *dev)
-{
- struct skge_port *skge = netdev_priv(dev);
-
- prefetch(skge->rx_ring.to_clean);
- netif_rx_schedule(dev);
-}
-
static irqreturn_t skge_intr(int irq, void *dev_id, struct pt_regs *regs)
{
struct skge_hw *hw = dev_id;
@@ -2874,13 +2865,15 @@
status &= hw->intr_mask;
if (status & IS_R1_F) {
+ skge_write8(hw, Q_ADDR(Q_R1, Q_CSR), CSR_IRQ_CL_F);
hw->intr_mask &= ~IS_R1_F;
- skge_wakeup(hw->dev[0]);
+ netif_rx_schedule(hw->dev[0]);
}
if (status & IS_R2_F) {
+ skge_write8(hw, Q_ADDR(Q_R2, Q_CSR), CSR_IRQ_CL_F);
hw->intr_mask &= ~IS_R2_F;
- skge_wakeup(hw->dev[1]);
+ netif_rx_schedule(hw->dev[1]);
}
if (status & IS_XA1_F)