ixgb: fix cache miss due to miscalculation
Reduce writeback threshold by 1. We were instructing the hardware to
wait until the 17th descriptor which went over the cache line limit.
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Auke Kok <auke.jan.h.kok@intel.com>
diff --git a/drivers/net/ixgb/ixgb_main.c b/drivers/net/ixgb/ixgb_main.c
index 7bbd447..770eef2 100644
--- a/drivers/net/ixgb/ixgb_main.c
+++ b/drivers/net/ixgb/ixgb_main.c
@@ -140,12 +140,12 @@
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
/* some defines for controlling descriptor fetches in h/w */
-#define RXDCTL_WTHRESH_DEFAULT 16 /* chip writes back at this many or RXT0 */
-#define RXDCTL_PTHRESH_DEFAULT 0 /* chip considers prefech below
- * this */
-#define RXDCTL_HTHRESH_DEFAULT 0 /* chip will only prefetch if tail
- * is pushed this many descriptors
- * from head */
+#define RXDCTL_WTHRESH_DEFAULT 15 /* chip writes back at this many or RXT0 */
+#define RXDCTL_PTHRESH_DEFAULT 0 /* chip considers prefech below
+ * this */
+#define RXDCTL_HTHRESH_DEFAULT 0 /* chip will only prefetch if tail
+ * is pushed this many descriptors
+ * from head */
/**
* ixgb_init_module - Driver Registration Routine