e1000: remove risky prefetch on next_skb->data

It was brought to our attention that the prefetches break e1000 traffic
on xscale/arm architectures.  Remove them for now.  We'll let them
stay in mm for a while, or find a better solution to enable.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index ed15fcaedaf9..97e71a4fe8eb 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -3519,7 +3519,7 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter,
         buffer_info = &rx_ring->buffer_info[i];
 
         while (rx_desc->status & E1000_RXD_STAT_DD) {
-                struct sk_buff *skb, *next_skb;
+                struct sk_buff *skb;
                 u8 status;
 #ifdef CONFIG_E1000_NAPI
                 if (*work_done >= work_to_do)
@@ -3537,8 +3537,6 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter,
                 prefetch(next_rxd);
 
                 next_buffer = &rx_ring->buffer_info[i];
-                next_skb = next_buffer->skb;
-                prefetch(next_skb->data - NET_IP_ALIGN);
 
                 cleaned = TRUE;
                 cleaned_count++;
@@ -3668,7 +3666,7 @@ e1000_clean_rx_irq_ps(struct e1000_adapter *adapter,
         struct e1000_buffer *buffer_info, *next_buffer;
         struct e1000_ps_page *ps_page;
         struct e1000_ps_page_dma *ps_page_dma;
-        struct sk_buff *skb, *next_skb;
+        struct sk_buff *skb;
         unsigned int i, j;
         uint32_t length, staterr;
         int cleaned_count = 0;
@@ -3697,8 +3695,6 @@ e1000_clean_rx_irq_ps(struct e1000_adapter *adapter,
                 prefetch(next_rxd);
 
                 next_buffer = &rx_ring->buffer_info[i];
-                next_skb = next_buffer->skb;
-                prefetch(next_skb->data - NET_IP_ALIGN);
 
                 cleaned = TRUE;
                 cleaned_count++;