[PATCH] sky2: prefetch tuning

Add a couple more prefetches to where we walk the rings.

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 54947ae99482f921280cbc486e822e42581701b0..39916e7cf6f9ec38f1b34f5200715196a317a71a 100644 (file)
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -45,6 +45,7 @@
 #include <linux/delay.h>
 #include <linux/workqueue.h>
 #include <linux/if_vlan.h>
+#include <linux/prefetch.h>
 #include <linux/mii.h>
 
 #include <asm/irq.h>
@@ -1248,6 +1249,7 @@ static void sky2_tx_complete(struct sky2_port *sky2, u16 done)
 
                nxt = re->idx;
                BUG_ON(nxt >= TX_RING_SIZE);
+               prefetch(sky2->tx_ring + nxt);
 
                /* Check for partial status */
                if (tx_dist(put, done) < tx_dist(put, nxt))
@@ -1659,6 +1661,7 @@ static struct sk_buff *sky2_receive(struct sky2_port *sky2,
                       sky2->netdev->name, sky2->rx_next, status, length);
 
        sky2->rx_next = (sky2->rx_next + 1) % sky2->rx_pending;
+       prefetch(sky2->rx_ring + sky2->rx_next);
 
        if (status & GMR_FS_ANY_ERR)
                goto error;