e1000/e1000e: implement a simple interrupt moderation

[safe/jmp/linux-2.6] / drivers / net / e1000e / netdev.c

diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 478c34a..c5f65a2 100644 (file)
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -52,7 +52,7 @@
 
 #include "e1000.h"
 
-#define DRV_VERSION "1.0.2-k2"
+#define DRV_VERSION "1.0.2-k4"
 char e1000e_driver_name[] = "e1000e";
 const char e1000e_driver_version[] = DRV_VERSION;
 
@@ -4070,6 +4070,22 @@ link_up:
                }
        }
 
+       /* Simple mode for Interrupt Throttle Rate (ITR) */
+       if (adapter->itr_setting == 4) {
+               /*
+                * Symmetric Tx/Rx gets a reduced ITR=2000;
+                * Total asymmetrical Tx or Rx gets ITR=8000;
+                * everyone else is between 2000-8000.
+                */
+               u32 goc = (adapter->gotc + adapter->gorc) / 10000;
+               u32 dif = (adapter->gotc > adapter->gorc ?
+                           adapter->gotc - adapter->gorc :
+                           adapter->gorc - adapter->gotc) / 10000;
+               u32 itr = goc > 0 ? (dif * 6000 / goc + 2000) : 8000;
+
+               ew32(ITR, 1000000000 / (itr * 256));
+       }
+
        /* Cause software interrupt to ensure Rx ring is cleaned */
        if (adapter->msix_entries)
                ew32(ICS, adapter->rx_ring->ims_val);