[PATCH] sky2: fix NAPI and receive handling
Speed up the receive and interrupt processing and eliminate a
couple of race conditions from NAPI code.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 92d69ff..a85a8d1 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -76,7 +76,7 @@
#define RX_LE_SIZE 256
#define RX_LE_BYTES (RX_LE_SIZE*sizeof(struct sky2_rx_le))
-#define RX_MAX_PENDING (RX_LE_SIZE/2 - 1)
+#define RX_MAX_PENDING (RX_LE_SIZE/2 - 2)
#define RX_DEF_PENDING 128
#define RX_COPY_THRESHOLD 256
@@ -690,7 +690,7 @@
setnew:
sky2_write16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX), idx);
}
- *last = sky2_read16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX));
+ *last = idx;
}
@@ -723,15 +723,6 @@
le->opcode = OP_PACKET | HW_OWNER;
}
-/* Tell receiver about new buffers. */
-static inline void rx_set_put(struct net_device *dev)
-{
- struct sky2_port *sky2 = netdev_priv(dev);
-
- if (sky2->rx_last_put != sky2->rx_put)
- sky2_put_idx(sky2->hw, rxqaddr[sky2->port], sky2->rx_put,
- &sky2->rx_last_put, RX_LE_SIZE);
-}
/* Tell chip where to start receive checksum.
* Actually has two checksums, but set both same to avoid possible byte
@@ -1616,6 +1607,10 @@
re->skb->ip_summed = CHECKSUM_NONE;
sky2_rx_add(sky2, re);
+ /* Tell receiver about new buffers. */
+ sky2_put_idx(sky2->hw, rxqaddr[sky2->port], sky2->rx_put,
+ &sky2->rx_last_put, RX_LE_SIZE);
+
return skb;
error:
@@ -1664,16 +1659,26 @@
hwidx = sky2_read16(hw, STAT_PUT_IDX);
BUG_ON(hwidx >= STATUS_RING_SIZE);
rmb();
- while (hw->st_idx != hwidx && work_done < to_do) {
+
+ do {
struct sky2_status_le *le = hw->st_le + hw->st_idx;
struct sky2_port *sky2;
struct sk_buff *skb;
u32 status;
u16 length;
- BUG_ON(le->link >= hw->ports);
- if (!hw->dev[le->link])
- goto skip;
+ /* Are we done yet? */
+ if (hw->st_idx == hwidx) {
+ sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
+ hwidx = sky2_read16(hw, STAT_PUT_IDX);
+ if (hwidx == hw->st_idx)
+ break;
+ }
+
+ hw->st_idx = (hw->st_idx + 1) % STATUS_RING_SIZE;
+ prefetch(&hw->st_le[hw->st_idx]);
+
+ BUG_ON(le->link >= hw->ports || !hw->dev[le->link]);
sky2 = netdev_priv(hw->dev[le->link]);
status = le32_to_cpu(le->status);
@@ -1692,6 +1697,7 @@
} else
#endif
netif_receive_skb(skb);
+ ++work_done;
break;
#ifdef SKY2_VLAN_TAG_USED
@@ -1722,22 +1728,11 @@
break;
}
- skip:
- hw->st_idx = (hw->st_idx + 1) % STATUS_RING_SIZE;
- if (hw->st_idx == hwidx) {
- hwidx = sky2_read16(hw, STAT_PUT_IDX);
- rmb();
- }
- }
+ le->opcode = 0; /* paranoia */
+ } while (work_done < to_do);
mmiowb();
- if (hw->dev[0])
- rx_set_put(hw->dev[0]);
-
- if (hw->dev[1])
- rx_set_put(hw->dev[1]);
-
*budget -= work_done;
dev0->quota -= work_done;
if (work_done < to_do) {
@@ -1750,10 +1745,10 @@
sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START);
}
+ netif_rx_complete(dev0);
hw->intr_mask |= Y2_IS_STAT_BMU;
sky2_write32(hw, B0_IMSK, hw->intr_mask);
sky2_read32(hw, B0_IMSK);
- netif_rx_complete(dev0);
}
return work_done >= to_do;
@@ -1880,6 +1875,7 @@
static irqreturn_t sky2_intr(int irq, void *dev_id, struct pt_regs *regs)
{
struct sky2_hw *hw = dev_id;
+ struct net_device *dev0 = hw->dev[0];
u32 status;
status = sky2_read32(hw, B0_Y2_SP_ISRC2);
@@ -1890,12 +1886,13 @@
sky2_hw_intr(hw);
/* Do NAPI for Rx and Tx status */
- if ((status & Y2_IS_STAT_BMU) && netif_rx_schedule_test(hw->dev[0])) {
- sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
-
+ if (status & Y2_IS_STAT_BMU) {
hw->intr_mask &= ~Y2_IS_STAT_BMU;
sky2_write32(hw, B0_IMSK, hw->intr_mask);
- __netif_rx_schedule(hw->dev[0]);
+ prefetch(&hw->st_le[hw->st_idx]);
+
+ if (netif_rx_schedule_test(dev0))
+ __netif_rx_schedule(dev0);
}
if (status & Y2_IS_IRQ_PHY1)