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>

diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c
index deca65330b0f19f2ed085b8c3aeb146db77017f2..ae9bb7b7fd6756d240c7b2587a8d6afd5d23c5ec 100644 (file)
--- 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)