[PATCH] e1000: dynamic itr: take TSO and jumbo into account

The dynamic interrupt rate control patches omitted proper counting
for jumbo's and TSO resulting in suboptimal interrupt mitigation strategies.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 24 insertions, 16 deletions

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 73f3a85fd238..62ef267b3d64 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -2628,29 +2628,34 @@ static unsigned int e1000_update_itr(struct e1000_adapter *adapter,
         if (packets == 0)
                 goto update_itr_done;
 
-
         switch (itr_setting) {
         case lowest_latency:
-                if ((packets < 5) && (bytes > 512))
+                /* jumbo frames get bulk treatment*/
+                if (bytes/packets > 8000)
+                        retval = bulk_latency;
+                else if ((packets < 5) && (bytes > 512))
                         retval = low_latency;
                 break;
         case low_latency:  /* 50 usec aka 20000 ints/s */
                 if (bytes > 10000) {
-                        if ((packets < 10) ||
-                             ((bytes/packets) > 1200))
+                        /* jumbo frames need bulk latency setting */
+                        if (bytes/packets > 8000)
+                                retval = bulk_latency;
+                        else if ((packets < 10) || ((bytes/packets) > 1200))
                                 retval = bulk_latency;
                         else if ((packets > 35))
                                 retval = lowest_latency;
-                } else if (packets <= 2 && bytes < 512)
+                } else if (bytes/packets > 2000)
+                        retval = bulk_latency;
+                else if (packets <= 2 && bytes < 512)
                         retval = lowest_latency;
                 break;
         case bulk_latency: /* 250 usec aka 4000 ints/s */
                 if (bytes > 25000) {
                         if (packets > 35)
                                 retval = low_latency;
-                } else {
-                        if (bytes < 6000)
-                                retval = low_latency;
+                } else if (bytes < 6000) {
+                        retval = low_latency;
                 }
                 break;
         }
@@ -2679,17 +2684,20 @@ static void e1000_set_itr(struct e1000_adapter *adapter)
                                     adapter->tx_itr,
                                     adapter->total_tx_packets,
                                     adapter->total_tx_bytes);
+        /* conservative mode (itr 3) eliminates the lowest_latency setting */
+        if (adapter->itr_setting == 3 && adapter->tx_itr == lowest_latency)
+                adapter->tx_itr = low_latency;
+
         adapter->rx_itr = e1000_update_itr(adapter,
                                     adapter->rx_itr,
                                     adapter->total_rx_packets,
                                     adapter->total_rx_bytes);
+        /* conservative mode (itr 3) eliminates the lowest_latency setting */
+        if (adapter->itr_setting == 3 && adapter->rx_itr == lowest_latency)
+                adapter->rx_itr = low_latency;
 
         current_itr = max(adapter->rx_itr, adapter->tx_itr);
 
-        /* conservative mode eliminates the lowest_latency setting */
-        if (current_itr == lowest_latency && (adapter->itr_setting == 3))
-                current_itr = low_latency;
-
         switch (current_itr) {
         /* counts and packets in update_itr are dependent on these numbers */
         case lowest_latency:
@@ -3868,11 +3876,11 @@ e1000_clean_tx_irq(struct e1000_adapter *adapter,
                         cleaned = (i == eop);
 
                         if (cleaned) {
-                                /* this packet count is wrong for TSO but has a
-                                 * tendency to make dynamic ITR change more
-                                 * towards bulk */
+                                struct sk_buff *skb = buffer_info->skb;
+                                unsigned int segs = skb_shinfo(skb)->gso_segs;
+                                total_tx_packets += segs;
                                 total_tx_packets++;
-                                total_tx_bytes += buffer_info->skb->len;
+                                total_tx_bytes += skb->len;
                         }
                         e1000_unmap_and_free_tx_resource(adapter, buffer_info);
                         tx_desc->upper.data = 0;