5 files changed, 48 insertions, 85 deletions

diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index ea5fb9fcc3f..d23b6682f4e 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -36,9 +36,6 @@
 #define TRACE_ON 1
 #define TRACE_OFF 0
 
-static void send_dm_alert(struct work_struct *unused);
-
-
 /*
  * Globals, our netlink socket pointer
  * and the work handle that will send up
@@ -48,11 +45,10 @@ static int trace_state = TRACE_OFF;
 static DEFINE_MUTEX(trace_state_mutex);
 
 struct per_cpu_dm_data {
-	struct work_struct dm_alert_work;
-	struct sk_buff __rcu *skb;
-	atomic_t dm_hit_count;
-	struct timer_list send_timer;
-	int cpu;
+	spinlock_t		lock;
+	struct sk_buff		*skb;
+	struct work_struct	dm_alert_work;
+	struct timer_list	send_timer;
 };
 
 struct dm_hw_stat_delta {
@@ -78,13 +74,13 @@ static int dm_delay = 1;
 static unsigned long dm_hw_check_delta = 2*HZ;
 static LIST_HEAD(hw_stats_list);
 
-static void reset_per_cpu_data(struct per_cpu_dm_data *data)
+static struct sk_buff *reset_per_cpu_data(struct per_cpu_dm_data *data)
 {
 	size_t al;
 	struct net_dm_alert_msg *msg;
 	struct nlattr *nla;
 	struct sk_buff *skb;
-	struct sk_buff *oskb = rcu_dereference_protected(data->skb, 1);
+	unsigned long flags;
 
 	al = sizeof(struct net_dm_alert_msg);
 	al += dm_hit_limit * sizeof(struct net_dm_drop_point);
@@ -99,65 +95,40 @@ static void reset_per_cpu_data(struct per_cpu_dm_data *data)
 				  sizeof(struct net_dm_alert_msg));
 		msg = nla_data(nla);
 		memset(msg, 0, al);
-	} else
-		schedule_work_on(data->cpu, &data->dm_alert_work);
-
-	/*
-	 * Don't need to lock this, since we are guaranteed to only
-	 * run this on a single cpu at a time.
-	 * Note also that we only update data->skb if the old and new skb
-	 * pointers don't match.  This ensures that we don't continually call
-	 * synchornize_rcu if we repeatedly fail to alloc a new netlink message.
-	 */
-	if (skb != oskb) {
-		rcu_assign_pointer(data->skb, skb);
-
-		synchronize_rcu();
-
-		atomic_set(&data->dm_hit_count, dm_hit_limit);
+	} else {
+		mod_timer(&data->send_timer, jiffies + HZ / 10);
 	}
 
+	spin_lock_irqsave(&data->lock, flags);
+	swap(data->skb, skb);
+	spin_unlock_irqrestore(&data->lock, flags);
+
+	return skb;
 }
 
-static void send_dm_alert(struct work_struct *unused)
+static void send_dm_alert(struct work_struct *work)
 {
 	struct sk_buff *skb;
-	struct per_cpu_dm_data *data = &get_cpu_var(dm_cpu_data);
+	struct per_cpu_dm_data *data;
 
-	WARN_ON_ONCE(data->cpu != smp_processor_id());
+	data = container_of(work, struct per_cpu_dm_data, dm_alert_work);
 
-	/*
-	 * Grab the skb we're about to send
-	 */
-	skb = rcu_dereference_protected(data->skb, 1);
-
-	/*
-	 * Replace it with a new one
-	 */
-	reset_per_cpu_data(data);
+	skb = reset_per_cpu_data(data);
 
-	/*
-	 * Ship it!
-	 */
 	if (skb)
 		genlmsg_multicast(skb, 0, NET_DM_GRP_ALERT, GFP_KERNEL);
-
-	put_cpu_var(dm_cpu_data);
 }
 
 /*
  * This is the timer function to delay the sending of an alert
  * in the event that more drops will arrive during the
- * hysteresis period.  Note that it operates under the timer interrupt
- * so we don't need to disable preemption here
+ * hysteresis period.
  */
-static void sched_send_work(unsigned long unused)
+static void sched_send_work(unsigned long _data)
 {
-	struct per_cpu_dm_data *data =  &get_cpu_var(dm_cpu_data);
-
-	schedule_work_on(smp_processor_id(), &data->dm_alert_work);
+	struct per_cpu_dm_data *data = (struct per_cpu_dm_data *)_data;
 
-	put_cpu_var(dm_cpu_data);
+	schedule_work(&data->dm_alert_work);
 }
 
 static void trace_drop_common(struct sk_buff *skb, void *location)
@@ -167,33 +138,28 @@ static void trace_drop_common(struct sk_buff *skb, void *location)
 	struct nlattr *nla;
 	int i;
 	struct sk_buff *dskb;
-	struct per_cpu_dm_data *data = &get_cpu_var(dm_cpu_data);
-
+	struct per_cpu_dm_data *data;
+	unsigned long flags;
 
-	rcu_read_lock();
-	dskb = rcu_dereference(data->skb);
+	local_irq_save(flags);
+	data = &__get_cpu_var(dm_cpu_data);
+	spin_lock(&data->lock);
+	dskb = data->skb;
 
 	if (!dskb)
 		goto out;
 
-	if (!atomic_add_unless(&data->dm_hit_count, -1, 0)) {
-		/*
-		 * we're already at zero, discard this hit
-		 */
-		goto out;
-	}
-
 	nlh = (struct nlmsghdr *)dskb->data;
 	nla = genlmsg_data(nlmsg_data(nlh));
 	msg = nla_data(nla);
 	for (i = 0; i < msg->entries; i++) {
 		if (!memcmp(&location, msg->points[i].pc, sizeof(void *))) {
 			msg->points[i].count++;
-			atomic_inc(&data->dm_hit_count);
 			goto out;
 		}
 	}
-
+	if (msg->entries == dm_hit_limit)
+		goto out;
 	/*
 	 * We need to create a new entry
 	 */
@@ -205,13 +171,11 @@ static void trace_drop_common(struct sk_buff *skb, void *location)
 
 	if (!timer_pending(&data->send_timer)) {
 		data->send_timer.expires = jiffies + dm_delay * HZ;
-		add_timer_on(&data->send_timer, smp_processor_id());
+		add_timer(&data->send_timer);
 	}
 
 out:
-	rcu_read_unlock();
-	put_cpu_var(dm_cpu_data);
-	return;
+	spin_unlock_irqrestore(&data->lock, flags);
 }
 
 static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location)
@@ -418,11 +382,11 @@ static int __init init_net_drop_monitor(void)
 
 	for_each_possible_cpu(cpu) {
 		data = &per_cpu(dm_cpu_data, cpu);
-		data->cpu = cpu;
 		INIT_WORK(&data->dm_alert_work, send_dm_alert);
 		init_timer(&data->send_timer);
-		data->send_timer.data = cpu;
+		data->send_timer.data = (unsigned long)data;
 		data->send_timer.function = sched_send_work;
+		spin_lock_init(&data->lock);
 		reset_per_cpu_data(data);
 	}
 
diff --git a/net/core/filter.c b/net/core/filter.c
index a3eddb515d1..d4ce2dc712e 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -616,9 +616,9 @@ static int __sk_prepare_filter(struct sk_filter *fp)
 /**
  *	sk_unattached_filter_create - create an unattached filter
  *	@fprog: the filter program
- *	@sk: the socket to use
+ *	@pfp: the unattached filter that is created
  *
- * Create a filter independent ofr any socket. We first run some
+ * Create a filter independent of any socket. We first run some
  * sanity checks on it to make sure it does not explode on us later.
  * If an error occurs or there is insufficient memory for the filter
  * a negative errno code is returned. On success the return is zero.
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index eb09f8bbbf0..d81d026138f 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -2219,9 +2219,7 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
 	rcu_read_lock_bh();
 	nht = rcu_dereference_bh(tbl->nht);
 
-	for (h = 0; h < (1 << nht->hash_shift); h++) {
-		if (h < s_h)
-			continue;
+	for (h = s_h; h < (1 << nht->hash_shift); h++) {
 		if (h > s_h)
 			s_idx = 0;
 		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
@@ -2260,9 +2258,7 @@ static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
 
 	read_lock_bh(&tbl->lock);
 
-	for (h = 0; h <= PNEIGH_HASHMASK; h++) {
-		if (h < s_h)
-			continue;
+	for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
 		if (h > s_h)
 			s_idx = 0;
 		for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
@@ -2297,7 +2293,7 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 	struct neigh_table *tbl;
 	int t, family, s_t;
 	int proxy = 0;
-	int err = 0;
+	int err;
 
 	read_lock(&neigh_tbl_lock);
 	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
@@ -2311,7 +2307,7 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 
 	s_t = cb->args[0];
 
-	for (tbl = neigh_tables, t = 0; tbl && (err >= 0);
+	for (tbl = neigh_tables, t = 0; tbl;
 	     tbl = tbl->next, t++) {
 		if (t < s_t || (family && tbl->family != family))
 			continue;
@@ -2322,6 +2318,8 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 			err = pneigh_dump_table(tbl, skb, cb);
 		else
 			err = neigh_dump_table(tbl, skb, cb);
+		if (err < 0)
+			break;
 	}
 	read_unlock(&neigh_tbl_lock);
 
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 3d84fb9d887..f9f40b932e4 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -362,22 +362,23 @@ EXPORT_SYMBOL(netpoll_send_skb_on_dev);
 
 void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
 {
-	int total_len, eth_len, ip_len, udp_len;
+	int total_len, ip_len, udp_len;
 	struct sk_buff *skb;
 	struct udphdr *udph;
 	struct iphdr *iph;
 	struct ethhdr *eth;
 
 	udp_len = len + sizeof(*udph);
-	ip_len = eth_len = udp_len + sizeof(*iph);
-	total_len = eth_len + ETH_HLEN + NET_IP_ALIGN;
+	ip_len = udp_len + sizeof(*iph);
+	total_len = ip_len + LL_RESERVED_SPACE(np->dev);
 
-	skb = find_skb(np, total_len, total_len - len);
+	skb = find_skb(np, total_len + np->dev->needed_tailroom,
+		       total_len - len);
 	if (!skb)
 		return;
 
 	skb_copy_to_linear_data(skb, msg, len);
-	skb->len += len;
+	skb_put(skb, len);
 
 	skb_push(skb, sizeof(*udph));
 	skb_reset_transport_header(skb);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 016694d6248..d78671e9d54 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3361,7 +3361,7 @@ EXPORT_SYMBOL(kfree_skb_partial);
  * @to: prior buffer
  * @from: buffer to add
  * @fragstolen: pointer to boolean
- *
+ * @delta_truesize: how much more was allocated than was requested
  */
 bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from,
 		      bool *fragstolen, int *delta_truesize)