---

yaml
---
r: 66278
b: refs/heads/master
c: b5427c2
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 17951f34b0970b05e29fd93a5b93fa05ec71308b
+refs/heads/master: b5427c27173e128dda1541bd9d3b05df79af5882

trunk/Documentation/networking/netconsole.txt

@@ -34,6 +34,12 @@ Examples:
 
  insmod netconsole netconsole=@/,@10.0.0.2/
 
+It also supports logging to multiple remote agents by specifying
+parameters for the multiple agents separated by semicolons and the
+complete string enclosed in "quotes", thusly:
+
+ modprobe netconsole netconsole="@/,@10.0.0.2/;@/eth1,6892@10.0.0.3/"
+
 Built-in netconsole starts immediately after the TCP stack is
 initialized and attempts to bring up the supplied dev at the supplied
 address.

trunk/drivers/net/netconsole.c

@@ -62,44 +62,93 @@ static int __init option_setup(char *opt)
 __setup("netconsole=", option_setup);
 #endif	/* MODULE */
 
+/* Linked list of all configured targets */
+static LIST_HEAD(target_list);
+
+/* This needs to be a spinlock because write_msg() cannot sleep */
+static DEFINE_SPINLOCK(target_list_lock);
+
 /**
  * struct netconsole_target - Represents a configured netconsole target.
+ * @list:	Links this target into the target_list.
  * @np:		The netpoll structure for this target.
  */
 struct netconsole_target {
+	struct list_head	list;
 	struct netpoll		np;
 };
 
-static struct netconsole_target default_target = {
-	.np		= {
-		.name		= "netconsole",
-		.dev_name	= "eth0",
-		.local_port	= 6665,
-		.remote_port	= 6666,
-		.remote_mac	= {0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
-	},
-};
+/* Allocate new target and setup netpoll for it */
+static struct netconsole_target *alloc_target(char *target_config)
+{
+	int err = -ENOMEM;
+	struct netconsole_target *nt;
+
+	/* Allocate and initialize with defaults */
+	nt = kzalloc(sizeof(*nt), GFP_KERNEL);
+	if (!nt) {
+		printk(KERN_ERR "netconsole: failed to allocate memory\n");
+		goto fail;
+	}
+
+	nt->np.name = "netconsole";
+	strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
+	nt->np.local_port = 6665;
+	nt->np.remote_port = 6666;
+	memset(nt->np.remote_mac, 0xff, ETH_ALEN);
+
+	/* Parse parameters and setup netpoll */
+	err = netpoll_parse_options(&nt->np, target_config);
+	if (err)
+		goto fail;
+
+	err = netpoll_setup(&nt->np);
+	if (err)
+		goto fail;
+
+	return nt;
+
+fail:
+	kfree(nt);
+	return ERR_PTR(err);
+}
+
+/* Cleanup netpoll for given target and free it */
+static void free_target(struct netconsole_target *nt)
+{
+	netpoll_cleanup(&nt->np);
+	kfree(nt);
+}
 
 /* Handle network interface device notifications */
 static int netconsole_netdev_event(struct notifier_block *this,
 				   unsigned long event,
 				   void *ptr)
 {
+	unsigned long flags;
+	struct netconsole_target *nt;
 	struct net_device *dev = ptr;
-	struct netconsole_target *nt = &default_target;
 
-	if (nt->np.dev == dev) {
-		switch (event) {
-		case NETDEV_CHANGEADDR:
-			memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN);
-			break;
+	if (!(event == NETDEV_CHANGEADDR || event == NETDEV_CHANGENAME))
+		goto done;
+
+	spin_lock_irqsave(&target_list_lock, flags);
+	list_for_each_entry(nt, &target_list, list) {
+		if (nt->np.dev == dev) {
+			switch (event) {
+			case NETDEV_CHANGEADDR:
+				memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN);
+				break;
 
-		case NETDEV_CHANGENAME:
-			strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
-			break;
+			case NETDEV_CHANGENAME:
+				strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
+				break;
+			}
 		}
 	}
+	spin_unlock_irqrestore(&target_list_lock, flags);
 
+done:
 	return NOTIFY_DONE;
 }
 
@@ -111,18 +160,32 @@ static void write_msg(struct console *con, const char *msg, unsigned int len)
 {
 	int frag, left;
 	unsigned long flags;
-	struct netconsole_target *nt = &default_target;
-
-	if (netif_running(nt->np.dev)) {
-		local_irq_save(flags);
-		for (left = len; left;) {
-			frag = min(left, MAX_PRINT_CHUNK);
-			netpoll_send_udp(&nt->np, msg, frag);
-			msg += frag;
-			left -= frag;
+	struct netconsole_target *nt;
+	const char *tmp;
+
+	/* Avoid taking lock and disabling interrupts unnecessarily */
+	if (list_empty(&target_list))
+		return;
+
+	spin_lock_irqsave(&target_list_lock, flags);
+	list_for_each_entry(nt, &target_list, list) {
+		if (netif_running(nt->np.dev)) {
+			/*
+			 * We nest this inside the for-each-target loop above
+			 * so that we're able to get as much logging out to
+			 * at least one target if we die inside here, instead
+			 * of unnecessarily keeping all targets in lock-step.
+			 */
+			tmp = msg;
+			for (left = len; left;) {
+				frag = min(left, MAX_PRINT_CHUNK);
+				netpoll_send_udp(&nt->np, tmp, frag);
+				tmp += frag;
+				left -= frag;
+			}
 		}
-		local_irq_restore(flags);
 	}
+	spin_unlock_irqrestore(&target_list_lock, flags);
 }
 
 static struct console netconsole = {
@@ -134,39 +197,67 @@ static struct console netconsole = {
 static int __init init_netconsole(void)
 {
 	int err = 0;
-	struct netconsole_target *nt = &default_target;
+	struct netconsole_target *nt, *tmp;
+	unsigned long flags;
+	char *target_config;
+	char *input = config;
 
-	if (!strnlen(config, MAX_PARAM_LENGTH)) {
+	if (!strnlen(input, MAX_PARAM_LENGTH)) {
 		printk(KERN_INFO "netconsole: not configured, aborting\n");
 		goto out;
 	}
 
-	err = netpoll_parse_options(&nt->np, config);
-	if (err)
-		goto out;
-
-	err = netpoll_setup(&nt->np);
-	if (err)
-		goto out;
+	while ((target_config = strsep(&input, ";"))) {
+		nt = alloc_target(target_config);
+		if (IS_ERR(nt)) {
+			err = PTR_ERR(nt);
+			goto fail;
+		}
+		spin_lock_irqsave(&target_list_lock, flags);
+		list_add(&nt->list, &target_list);
+		spin_unlock_irqrestore(&target_list_lock, flags);
+	}
 
 	err = register_netdevice_notifier(&netconsole_netdev_notifier);
 	if (err)
-		goto out;
+		goto fail;
 
 	register_console(&netconsole);
 	printk(KERN_INFO "netconsole: network logging started\n");
 
 out:
 	return err;
+
+fail:
+	printk(KERN_ERR "netconsole: cleaning up\n");
+
+	/*
+	 * Remove all targets and destroy them. Skipping the list
+	 * lock is safe here, and netpoll_cleanup() will sleep.
+	 */
+	list_for_each_entry_safe(nt, tmp, &target_list, list) {
+		list_del(&nt->list);
+		free_target(nt);
+	}
+
+	return err;
 }
 
 static void __exit cleanup_netconsole(void)
 {
-	struct netconsole_target *nt = &default_target;
+	struct netconsole_target *nt, *tmp;
 
 	unregister_console(&netconsole);
 	unregister_netdevice_notifier(&netconsole_netdev_notifier);
-	netpoll_cleanup(&nt->np);
+
+	/*
+	 * Remove all targets and destroy them. Skipping the list
+	 * lock is safe here, and netpoll_cleanup() will sleep.
+	 */
+	list_for_each_entry_safe(nt, tmp, &target_list, list) {
+		list_del(&nt->list);
+		free_target(nt);
+	}
 }
 
 module_init(init_netconsole);