myri10ge: Use the pause counter to avoid a needless device reset

Use the pause counter to avoid a needless device reset, and
print a message telling the admin that our link partner is
flow controlling us down to 0 pkts/sec.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 18 insertions, 7 deletions

diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c
index deca65330b0f..ae9bb7b7fd67 100644
--- a/drivers/net/myri10ge/myri10ge.c
+++ b/drivers/net/myri10ge/myri10ge.c
@@ -191,6 +191,7 @@ struct myri10ge_priv {
         struct timer_list watchdog_timer;
         int watchdog_tx_done;
         int watchdog_tx_req;
+        int watchdog_pause;
         int watchdog_resets;
         int tx_linearized;
         int pause;
@@ -2800,6 +2801,7 @@ static void myri10ge_watchdog(struct work_struct *work)
 static void myri10ge_watchdog_timer(unsigned long arg)
 {
         struct myri10ge_priv *mgp;
+        u32 rx_pause_cnt;
 
         mgp = (struct myri10ge_priv *)arg;
 
@@ -2816,19 +2818,28 @@ static void myri10ge_watchdog_timer(unsigned long arg)
                     myri10ge_fill_thresh)
                         mgp->rx_big.watchdog_needed = 0;
         }
+        rx_pause_cnt = ntohl(mgp->fw_stats->dropped_pause);
 
         if (mgp->tx.req != mgp->tx.done &&
             mgp->tx.done == mgp->watchdog_tx_done &&
-            mgp->watchdog_tx_req != mgp->watchdog_tx_done)
+            mgp->watchdog_tx_req != mgp->watchdog_tx_done) {
                 /* nic seems like it might be stuck.. */
-                schedule_work(&mgp->watchdog_work);
-        else
-                /* rearm timer */
-                mod_timer(&mgp->watchdog_timer,
-                          jiffies + myri10ge_watchdog_timeout * HZ);
-
+                if (rx_pause_cnt != mgp->watchdog_pause) {
+                        if (net_ratelimit())
+                                printk(KERN_WARNING "myri10ge %s:"
+                                       "TX paused, check link partner\n",
+                                       mgp->dev->name);
+                } else {
+                        schedule_work(&mgp->watchdog_work);
+                        return;
+                }
+        }
+        /* rearm timer */
+        mod_timer(&mgp->watchdog_timer,
+                  jiffies + myri10ge_watchdog_timeout * HZ);
         mgp->watchdog_tx_done = mgp->tx.done;
         mgp->watchdog_tx_req = mgp->tx.req;
+        mgp->watchdog_pause = rx_pause_cnt;
 }
 
 static int myri10ge_probe(struct pci_dev *pdev, const struct pci_device_id *ent)