net: Print the module name as part of the watchdog message

As suggested by Dave:

This patch adds a function to get the driver name from a struct net_device,
and consequently uses this in the watchdog timeout handler to print as 
part of the message. 

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 25 insertions, 3 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 812bcd8b4363..f5ea445f89f0 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1645,6 +1645,8 @@ extern void dev_seq_stop(struct seq_file *seq, void *v);
 extern int netdev_class_create_file(struct class_attribute *class_attr);
 extern void netdev_class_remove_file(struct class_attribute *class_attr);
 
+extern char *netdev_drivername(struct net_device *dev, char *buffer, int len);
+
 extern void linkwatch_run_queue(void);
 
 extern int netdev_compute_features(unsigned long all, unsigned long one);
diff --git a/net/core/dev.c b/net/core/dev.c
index 1698b3998981..ad5598d2bb37 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4686,6 +4686,26 @@ err_name:
         return -ENOMEM;
 }
 
+char *netdev_drivername(struct net_device *dev, char *buffer, int len)
+{
+        struct device_driver *driver;
+        struct device *parent;
+
+        if (len <= 0 || !buffer)
+                return buffer;
+        buffer[0] = 0;
+
+        parent = dev->dev.parent;
+
+        if (!parent)
+                return buffer;
+
+        driver = parent->driver;
+        if (driver && driver->name)
+                strlcpy(buffer, driver->name, len);
+        return buffer;
+}
+
 static void __net_exit netdev_exit(struct net *net)
 {
         kfree(net->dev_name_head);
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index cb625b4d6da5..4ac7e3a8c253 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -212,9 +212,9 @@ static void dev_watchdog(unsigned long arg)
                         if (some_queue_stopped &&
                             time_after(jiffies, (dev->trans_start +
                                                  dev->watchdog_timeo))) {
-                                printk(KERN_INFO "NETDEV WATCHDOG: %s: "
-                                       "transmit timed out\n",
-                                       dev->name);
+                                char drivername[64];
+                                printk(KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit timed out\n",
+                                       dev->name, netdev_drivername(dev, drivername, 64));
                                 dev->tx_timeout(dev);
                                 WARN_ON_ONCE(1);
                         }