net: mhi: mhdp optimizations and typo corrections

mhdp driver optimizations and typo corrections

Bug 1167018

Change-Id: Icc829b4c42bee941ceb361cb0c04d01ece6cbf14
Signed-off-by: wtsai <wtsai@nvidia.com>
Reviewed-on: http://git-master/r/165099
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>

1 files changed, 169 insertions, 57 deletions

diff --git a/net/mhi/l3mhdp.c b/net/mhi/l3mhdp.c
index 6acf1f6fee91..1771050d0a71 100644
--- a/net/mhi/l3mhdp.c
+++ b/net/mhi/l3mhdp.c
@@ -42,6 +42,8 @@
 #define MHDP_BONDING_SUPPORT
 #endif
 
+/*#define MHDP_USE_NAPI*/
+
 #ifdef MHDP_BONDING_SUPPORT
 #include <linux/etherdevice.h>
 #endif /* MHDP_BONDING_SUPPORT */
@@ -53,6 +55,7 @@
 /* MHDP device MTU limits */
 #define MHDP_MTU_MAX		0x2400
 #define MHDP_MTU_MIN		0x44
+#define MAX_MHDP_FRAME_SIZE	16000
 
 /* MHDP device names */
 #define MHDP_IFNAME		"rmnet%d"
@@ -85,8 +88,11 @@ int sysctl_mhdp_concat_nb_pkt __read_mostly;
 EXPORT_SYMBOL(sysctl_mhdp_concat_nb_pkt);
 
 /*** Type definitions ***/
+#ifdef MHDP_USE_NAPI
+#define NAPI_WEIGHT 64
+#endif /*MHDP_USE_NAPI*/
 
-#define MAX_MHDPHDR_SIZE 10
+#define MAX_MHDPHDR_SIZE 18
 
 struct mhdp_tunnel {
 	struct mhdp_tunnel	*next;
@@ -103,6 +109,11 @@ struct mhdp_tunnel {
 struct mhdp_net {
 	struct mhdp_tunnel	*tunnels;
 	struct net_device	*ctl_dev;
+#ifdef MHDP_USE_NAPI
+	struct net_device	*dev;
+	struct napi_struct	napi;
+	struct sk_buff_head	skb_list;
+#endif /*#ifdef MHDP_USE_NAPI*/
 };
 
 struct packet_info {
@@ -121,13 +132,19 @@ struct mhdp_hdr {
 
 static void mhdp_netdev_setup(struct net_device *dev);
 
-static void mhdp_submit_queued_skb(struct mhdp_tunnel *tunnel);
+static void mhdp_submit_queued_skb(struct mhdp_tunnel *tunnel, int force_send);
 
 static int mhdp_netdev_event(struct notifier_block *this,
 			     unsigned long event, void *ptr);
 
 static void tx_timer_timeout(unsigned long arg);
 
+#ifdef MHDP_USE_NAPI
+
+static int mhdp_poll(struct napi_struct *napi, int budget);
+
+#endif /*MHDP_USE_NAPI*/
+
 /*** Global Variables ***/
 
 static int  mhdp_net_id __read_mostly;
@@ -319,6 +336,7 @@ mhdp_netdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 			} else {
 				err = -EINVAL;
 			}
+
 		} else if (1 == tunnel->free_pdn) {
 
 			tunnel->free_pdn = 0;
@@ -381,7 +399,7 @@ mhdp_netdev_uninit(struct net_device *dev)
 
 
 static void
-mhdp_submit_queued_skb(struct mhdp_tunnel *tunnel)
+mhdp_submit_queued_skb(struct mhdp_tunnel *tunnel, int force_send)
 {
 	struct sk_buff *skb = tunnel->skb;
 	struct l2muxhdr	*l2hdr;
@@ -416,7 +434,10 @@ mhdp_submit_queued_skb(struct mhdp_tunnel *tunnel)
 		dev_queue_xmit(skb);
 
 		for (i = 0; i < nb_frags; i++)
-			dev_kfree_skb(tunnel->skb_to_free[i]);
+			if (tunnel->skb_to_free[i])
+				dev_kfree_skb(tunnel->skb_to_free[i]);
+			else
+				EPRINTK("submit_q_skb: error no skb to free\n");
 	}
 }
 
@@ -517,16 +538,18 @@ mhdp_netdev_rx(struct sk_buff *skb, struct net_device *dev)
 				goto error;
 
 			get_page(page);
-			skb_add_rx_frag(newskb, skb_shinfo(newskb)->nr_frags,
-			page,
-			frag->page_offset +
-			((mhdp_header_len - skb_headlen(skb)) + offset),
-			length, PAGE_SIZE);
+			skb_add_rx_frag(newskb,
+				skb_shinfo(newskb)->nr_frags,
+				page,
+				frag->page_offset +
+				((mhdp_header_len - skb_headlen(skb)) + offset),
+				length,
+				PAGE_SIZE);
 
 			ip_ver = *((unsigned long *)page_address(page) +
-			(frag->page_offset +
-			((mhdp_header_len - skb_headlen(skb)) + offset)));
-
+					(frag->page_offset +
+					((mhdp_header_len - skb_headlen(skb)) +
+					offset)));
 			if ((ip_ver>>4) != VER_IPv4 &&
 				(ip_ver>>4) != VER_IPv6)
 				goto error;
@@ -538,8 +561,9 @@ mhdp_netdev_rx(struct sk_buff *skb, struct net_device *dev)
 
 		skb_reset_network_header(newskb);
 
-		/* IPv6 Support - Check the IP version and set
-		ETH_P_IP or ETH_P_IPv6 for received packets */
+		/* IPv6 Support - Check the IP version */
+		/* and set ETH_P_IP or ETH_P_IPv6 for received packets */
+
 		newskb->protocol = htons(ETH_IP_TYPE(ip_ver));
 
 		newskb->pkt_type = PACKET_HOST;
@@ -552,7 +576,11 @@ mhdp_netdev_rx(struct sk_buff *skb, struct net_device *dev)
 			stats->rx_packets++;
 			newskb->dev = tunnel->dev;
 			SKBPRINT(newskb, "NEWSKB: RX");
+#ifdef MHDP_USE_NAPI
+			netif_receive_skb(newskb);
+#else
 			netif_rx(newskb);
+#endif /*#ifdef MHDP_USE_NAPI*/
 		}
 	}
 	rcu_read_unlock();
@@ -573,18 +601,60 @@ error:
 	return err;
 }
 
+#ifdef MHDP_USE_NAPI
+/*
+static int mhdp_poll(struct napi_struct *napi, int budget)
+function called through napi to read current ip frame received
+*/
+static int mhdp_poll(struct napi_struct *napi, int budget)
+{
+	struct mhdp_net *mhdpn = container_of(napi, struct mhdp_net, napi);
+	int err = 0;
+	struct sk_buff *skb;
+
+	while (!skb_queue_empty(&mhdpn->skb_list)) {
+
+		skb = skb_dequeue(&mhdpn->skb_list);
+		err = mhdp_netdev_rx(skb, mhdpn->dev);
+	}
+
+	napi_complete(napi);
+
+	return err;
+}
+/*l2mux callback*/
+static int
+mhdp_netdev_rx_napi(struct sk_buff *skb, struct net_device *dev)
+{
+	struct mhdp_net *mhdpn = mhdp_net_dev(dev);
+
+
+	if (mhdpn) {
+
+		mhdpn->dev = dev;
+		skb_queue_tail(&mhdpn->skb_list, skb);
+
+		napi_schedule(&mhdpn->napi);
+
+	} else {
+		EPRINTK("mhdp_netdev_rx_napi-MHDP driver init not correct\n");
+	}
+
+	return 0;
+}
+#endif /*MHDP_USE_NAPI*/
+
 static void tx_timer_timeout(unsigned long arg)
 {
 	struct mhdp_tunnel *tunnel = (struct mhdp_tunnel *) arg;
 
 	spin_lock(&tunnel->timer_lock);
 
-	mhdp_submit_queued_skb(tunnel);
+	mhdp_submit_queued_skb(tunnel, 1);
 
 	spin_unlock(&tunnel->timer_lock);
 }
 
-
 static int
 mhdp_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 {
@@ -602,9 +672,27 @@ mhdp_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (timer_pending(&tunnel->tx_timer))
 		del_timer(&tunnel->tx_timer);
 
+#if 0
+	{
+		int i;
+		int len = skb->len;
+		u8 *ptr = skb->data;
+
+		for (i = 0; i < len; i++) {
+			if (i%8 == 0)
+				printk(KERN_DEBUG
+					"MHDP mhdp_netdev_xmit: TX [%04X] ", i);
+			printk(" 0x%02X", ptr[i]);
+			if (i%8 == 7 || i == len-1)
+				printk("\n");
+		}
+	}
+#endif
+xmit_again:
+
 	if (tunnel->skb == NULL) {
 		tunnel->skb = netdev_alloc_skb(dev,
-			L2MUX_HDR_SIZE + sizeof(struct mhdp_hdr) + ETH_HLEN);
+			L2MUX_HDR_SIZE + sizeof(struct mhdp_hdr));
 
 		if (!tunnel->skb) {
 			EPRINTK("mhdp_netdev_xmit error1");
@@ -633,10 +721,19 @@ mhdp_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 		mhdpHdr->packet_count = 0;
 	}
 
+	/*This new frame is to big for the current mhdp frame,
+	* send the frame first*/
+	if (tunnel->skb->len + skb->len >= MAX_MHDP_FRAME_SIZE) {
+
+		mhdp_submit_queued_skb(tunnel, 1);
+
+		goto xmit_again;
+
+	} else {
+
 	/*
 	 * skb_put cannot be called as the (data_len != 0)
 	 */
-	{
 		tunnel->skb->tail += sizeof(struct packet_info);
 		tunnel->skb->len  += sizeof(struct packet_info);
 
@@ -644,58 +741,63 @@ mhdp_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 				(unsigned long)tunnel->skb->tail,
 				(unsigned long)tunnel->skb->end,
 				(unsigned long)tunnel->skb->data_len);
-	}
 
-	mhdpHdr = (struct mhdp_hdr *)tunnel->skb->data;
+		mhdpHdr = (struct mhdp_hdr *)tunnel->skb->data;
 
-	tunnel->skb_to_free[mhdpHdr->packet_count] = skb;
+		tunnel->skb_to_free[mhdpHdr->packet_count] = skb;
 
-	packet_count = mhdpHdr->packet_count;
-	mhdpHdr->info[packet_count].pdn_id = tunnel->pdn_id;
-	if (packet_count == 0) {
-		mhdpHdr->info[packet_count].packet_offset = 0;
-	} else {
-		mhdpHdr->info[packet_count].packet_offset =
-			mhdpHdr->info[packet_count - 1].packet_offset +
-			mhdpHdr->info[packet_count - 1].packet_length;
-	}
+		packet_count = mhdpHdr->packet_count;
+		mhdpHdr->info[packet_count].pdn_id = tunnel->pdn_id;
+		if (packet_count == 0) {
+			mhdpHdr->info[packet_count].packet_offset = 0;
+		} else {
+			mhdpHdr->info[packet_count].packet_offset =
+				mhdpHdr->info[packet_count - 1].packet_offset +
+				mhdpHdr->info[packet_count - 1].packet_length;
+		}
 
-	mhdpHdr->info[packet_count].packet_length = skb->len;
-	mhdpHdr->packet_count++;
+		mhdpHdr->info[packet_count].packet_length = skb->len;
+		mhdpHdr->packet_count++;
 
-	page = virt_to_page(skb->data);
+		page = virt_to_page(skb->data);
 
-	if (page == NULL) {
-		EPRINTK("kmap_atomic_to_page returns NULL");
-		goto tx_error;
-	}
+		if (page == NULL) {
+			EPRINTK("kmap_atomic_to_page returns NULL");
+			goto tx_error;
+		}
 
-	get_page(page);
+		get_page(page);
 
-	offset = ((unsigned long)skb->data -
-		  (unsigned long)page_address(page));
+		offset = ((unsigned long)skb->data -
+			  (unsigned long)page_address(page));
 
-	skb_add_rx_frag(tunnel->skb, skb_shinfo(tunnel->skb)->nr_frags,
+		skb_add_rx_frag(tunnel->skb, skb_shinfo(tunnel->skb)->nr_frags,
 			page, offset, skb_headlen(skb), PAGE_SIZE);
 
-	if (skb_shinfo(skb)->nr_frags) {
-		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-			skb_frag_t *frag = &skb_shinfo(tunnel->skb)->frags[i];
-			get_page(skb_frag_page(frag));
-			skb_add_rx_frag(tunnel->skb,
+		if (skb_shinfo(skb)->nr_frags) {
+			for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+				skb_frag_t *frag =
+					&skb_shinfo(tunnel->skb)->frags[i];
+
+				get_page(skb_frag_page(frag));
+				skb_add_rx_frag(tunnel->skb,
 					skb_shinfo(tunnel->skb)->nr_frags,
-					skb_frag_page(frag), frag->page_offset,
-					frag->size, PAGE_SIZE);
+					skb_frag_page(frag),
+					frag->page_offset,
+					frag->size,
+					PAGE_SIZE);
+			}
 		}
-	}
 
-	if (mhdpHdr->packet_count == MAX_MHDPHDR_SIZE) {
-		mhdp_submit_queued_skb(tunnel);
-	} else {
-	    tunnel->tx_timer.function = &tx_timer_timeout;
-	    tunnel->tx_timer.data     = (unsigned long) tunnel;
-	    tunnel->tx_timer.expires = jiffies + ((HZ + 999) / 1000) ;
-	    add_timer(&tunnel->tx_timer);
+		if (mhdpHdr->packet_count >= MAX_MHDPHDR_SIZE) {
+			mhdp_submit_queued_skb(tunnel, 1);
+		} else {
+			tunnel->tx_timer.function = &tx_timer_timeout;
+			tunnel->tx_timer.data     = (unsigned long) tunnel;
+			tunnel->tx_timer.expires =
+				jiffies + ((HZ + 999) / 1000);
+			add_timer(&tunnel->tx_timer);
+		}
 	}
 
 	spin_unlock(&tunnel->timer_lock);
@@ -730,7 +832,8 @@ mhdp_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
 			iter; prev = iter, iter = iter->next) {
 			if (event_dev == iter->master_dev) {
 				if (!prev)
-					mhdpn->tunnels = mhdpn->tunnels->next;
+					mhdpn->tunnels =
+						mhdpn->tunnels->next;
 				else
 					prev->next = iter->next;
 				mhdp_tunnel_destroy(iter->dev);
@@ -817,6 +920,11 @@ static int __net_init mhdp_init_net(struct net *net)
 		return err;
 	}
 
+#ifdef MHDP_USE_NAPI
+	netif_napi_add(mhdpn->ctl_dev, &mhdpn->napi, mhdp_poll, NAPI_WEIGHT);
+	napi_enable(&mhdpn->napi);
+	skb_queue_head_init(&mhdpn->skb_list);
+#endif /*#ifdef MHDP_USE_NAPI*/
 	return 0;
 }
 
@@ -842,7 +950,11 @@ static int __init mhdp_init(void)
 {
 	int err;
 
+#ifdef MHDP_USE_NAPI
+	err = l2mux_netif_rx_register(MHI_L3_MHDP_DL, mhdp_netdev_rx_napi);
+#else
 	err = l2mux_netif_rx_register(MHI_L3_MHDP_DL, mhdp_netdev_rx);
+#endif /* MHDP_USE_NAPI */
 	if (err)
 		goto rollback0;