e1000: FIX: Disable Packet Split for non jumbo frames

Allocations using alloc_page are taking too long for normal MTU, so
use LPE only for jumbo frames.

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

drivers/net/e1000/e1000_main.c

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index fb83082..7362e12 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -1808,9 +1808,11 @@
 	 * followed by the page buffers.  Therefore, skb->data is
 	 * sized to hold the largest protocol header.
 	 */
+	/* allocations using alloc_page take too long for regular MTU
+	 * so only enable packet split for jumbo frames */
 	pages = PAGE_USE_COUNT(adapter->netdev->mtu);
-	if ((adapter->hw.mac_type > e1000_82547_rev_2) && (pages <= 3) &&
-	    PAGE_SIZE <= 16384)
+	if ((adapter->hw.mac_type >= e1000_82571) && (pages <= 3) &&
+	    PAGE_SIZE <= 16384 && (rctl & E1000_RCTL_LPE))
 		adapter->rx_ps_pages = pages;
 	else
 		adapter->rx_ps_pages = 0;