1 files changed, 51 insertions, 17 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index ecec802..bcf01af 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -110,7 +110,7 @@ struct tap_filter {
 	unsigned char	addr[FLT_EXACT_COUNT][ETH_ALEN];
 };
 
-/* DEFAULT_MAX_NUM_RSS_QUEUES were choosed to let the rx/tx queues allocated for
+/* DEFAULT_MAX_NUM_RSS_QUEUES were chosen to let the rx/tx queues allocated for
  * the netdevice to be fit in one page. So we can make sure the success of
  * memory allocation. TODO: increase the limit. */
 #define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES
@@ -119,7 +119,7 @@ struct tap_filter {
 #define TUN_FLOW_EXPIRE (3 * HZ)
 
 /* A tun_file connects an open character device to a tuntap netdevice. It
- * also contains all socket related strctures (except sock_fprog and tap_filter)
+ * also contains all socket related structures (except sock_fprog and tap_filter)
  * to serve as one transmit queue for tuntap device. The sock_fprog and
  * tap_filter were kept in tun_struct since they were used for filtering for the
  * netdevice not for a specific queue (at least I didn't see the requirement for
@@ -152,6 +152,7 @@ struct tun_flow_entry {
 	struct tun_struct *tun;
 
 	u32 rxhash;
+	u32 rps_rxhash;
 	int queue_index;
 	unsigned long updated;
 };
@@ -220,6 +221,7 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun,
 			  rxhash, queue_index);
 		e->updated = jiffies;
 		e->rxhash = rxhash;
+		e->rps_rxhash = 0;
 		e->queue_index = queue_index;
 		e->tun = tun;
 		hlist_add_head_rcu(&e->hash_link, head);
@@ -232,6 +234,7 @@ static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e)
 {
 	tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n",
 		  e->rxhash, e->queue_index);
+	sock_rps_reset_flow_hash(e->rps_rxhash);
 	hlist_del_rcu(&e->hash_link);
 	kfree_rcu(e, rcu);
 	--tun->flow_count;
@@ -325,6 +328,7 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash,
 		/* TODO: keep queueing to old queue until it's empty? */
 		e->queue_index = queue_index;
 		e->updated = jiffies;
+		sock_rps_record_flow_hash(e->rps_rxhash);
 	} else {
 		spin_lock_bh(&tun->lock);
 		if (!tun_flow_find(head, rxhash) &&
@@ -341,8 +345,20 @@ unlock:
 	rcu_read_unlock();
 }
 
+/**
+ * Save the hash received in the stack receive path and update the
+ * flow_hash table accordingly.
+ */
+static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry *e, u32 hash)
+{
+	if (unlikely(e->rps_rxhash != hash)) {
+		sock_rps_reset_flow_hash(e->rps_rxhash);
+		e->rps_rxhash = hash;
+	}
+}
+
 /* We try to identify a flow through its rxhash first. The reason that
- * we do not check rxq no. is becuase some cards(e.g 82599), chooses
+ * we do not check rxq no. is because some cards(e.g 82599), chooses
  * the rxq based on the txq where the last packet of the flow comes. As
  * the userspace application move between processors, we may get a
  * different rxq no. here. If we could not get rxhash, then we would
@@ -359,12 +375,13 @@ static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb,
 	rcu_read_lock();
 	numqueues = ACCESS_ONCE(tun->numqueues);
 
-	txq = skb_get_rxhash(skb);
+	txq = skb_get_hash(skb);
 	if (txq) {
 		e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq);
-		if (e)
+		if (e) {
+			tun_flow_save_rps_rxhash(e, txq);
 			txq = e->queue_index;
-		else
+		} else
 			/* use multiply and shift instead of expensive divide */
 			txq = ((u64)txq * numqueues) >> 32;
 	} else if (likely(skb_rx_queue_recorded(skb))) {
@@ -532,7 +549,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filte
 
 	err = 0;
 
-	/* Re-attach the filter to presist device */
+	/* Re-attach the filter to persist device */
 	if (!skip_filter && (tun->filter_attached == true)) {
 		err = sk_attach_filter(&tun->fprog, tfile->socket.sk);
 		if (!err)
@@ -721,14 +738,32 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct tun_struct *tun = netdev_priv(dev);
 	int txq = skb->queue_mapping;
 	struct tun_file *tfile;
+	u32 numqueues = 0;
 
 	rcu_read_lock();
 	tfile = rcu_dereference(tun->tfiles[txq]);
+	numqueues = ACCESS_ONCE(tun->numqueues);
 
 	/* Drop packet if interface is not attached */
-	if (txq >= tun->numqueues)
+	if (txq >= numqueues)
 		goto drop;
 
+	if (numqueues == 1) {
+		/* Select queue was not called for the skbuff, so we extract the
+		 * RPS hash and save it into the flow_table here.
+		 */
+		__u32 rxhash;
+
+		rxhash = skb_get_hash(skb);
+		if (rxhash) {
+			struct tun_flow_entry *e;
+			e = tun_flow_find(&tun->flows[tun_hashfn(rxhash)],
+					rxhash);
+			if (e)
+				tun_flow_save_rps_rxhash(e, rxhash);
+		}
+	}
+
 	tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
 
 	BUG_ON(!tfile);
@@ -746,8 +781,8 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
 	/* Limit the number of packets queued by dividing txq length with the
 	 * number of queues.
 	 */
-	if (skb_queue_len(&tfile->socket.sk->sk_receive_queue)
-			  >= dev->tx_queue_len / tun->numqueues)
+	if (skb_queue_len(&tfile->socket.sk->sk_receive_queue) * numqueues
+			  >= dev->tx_queue_len)
 		goto drop;
 
 	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
@@ -820,9 +855,9 @@ static void tun_poll_controller(struct net_device *dev)
 	 * Tun only receives frames when:
 	 * 1) the char device endpoint gets data from user space
 	 * 2) the tun socket gets a sendmsg call from user space
-	 * Since both of those are syncronous operations, we are guaranteed
+	 * Since both of those are synchronous operations, we are guaranteed
 	 * never to have pending data when we poll for it
-	 * so theres nothing to do here but return.
+	 * so there is nothing to do here but return.
 	 * We need this though so netpoll recognizes us as an interface that
 	 * supports polling, which enables bridge devices in virt setups to
 	 * still use netconsole
@@ -1147,7 +1182,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 	skb_reset_network_header(skb);
 	skb_probe_transport_header(skb, 0);
 
-	rxhash = skb_get_rxhash(skb);
+	rxhash = skb_get_hash(skb);
 	netif_rx_ni(skb);
 
 	tun->dev->stats.rx_packets++;
@@ -1292,8 +1327,7 @@ done:
 }
 
 static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
-			   struct kiocb *iocb, const struct iovec *iv,
-			   ssize_t len, int noblock)
+			   const struct iovec *iv, ssize_t len, int noblock)
 {
 	DECLARE_WAITQUEUE(wait, current);
 	struct sk_buff *skb;
@@ -1356,7 +1390,7 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
 		goto out;
 	}
 
-	ret = tun_do_read(tun, tfile, iocb, iv, len,
+	ret = tun_do_read(tun, tfile, iv, len,
 			  file->f_flags & O_NONBLOCK);
 	ret = min_t(ssize_t, ret, len);
 	if (ret > 0)
@@ -1457,7 +1491,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
 					 SOL_PACKET, TUN_TX_TIMESTAMP);
 		goto out;
 	}
-	ret = tun_do_read(tun, tfile, iocb, m->msg_iov, total_len,
+	ret = tun_do_read(tun, tfile, m->msg_iov, total_len,
 			  flags & MSG_DONTWAIT);
 	if (ret > total_len) {
 		m->msg_flags |= MSG_TRUNC;