[IPV4]: Add raw drops counter.

Add raw drops counter for IPv4 in /proc/net/raw .
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sock.h

@@ -145,7 +145,8 @@ struct sock_common {
   *	@sk_forward_alloc: space allocated forward
   *	@sk_allocation: allocation mode
   *	@sk_sndbuf: size of send buffer in bytes
-  *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, %SO_OOBINLINE settings
+  *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
+  *		   %SO_OOBINLINE settings
   *	@sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
@@ -153,9 +154,12 @@ struct sock_common {
   *	@sk_backlog: always used with the per-socket spinlock held
   *	@sk_callback_lock: used with the callbacks in the end of this struct
   *	@sk_error_queue: rarely used
-  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, IPV6_ADDRFORM for instance)
+  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
+  *			  IPV6_ADDRFORM for instance)
   *	@sk_err: last error
-  *	@sk_err_soft: errors that don't cause failure but are the cause of a persistent failure not just 'timed out'
+  *	@sk_err_soft: errors that don't cause failure but are the cause of a
+  *		      persistent failure not just 'timed out'
+  *	@sk_drops: raw drops counter
   *	@sk_ack_backlog: current listen backlog
   *	@sk_max_ack_backlog: listen backlog set in listen()
   *	@sk_priority: %SO_PRIORITY setting
@@ -239,6 +243,7 @@ struct sock {
 	rwlock_t		sk_callback_lock;
 	int			sk_err,
 				sk_err_soft;
+	atomic_t		sk_drops;
 	unsigned short		sk_ack_backlog;
 	unsigned short		sk_max_ack_backlog;
 	__u32			sk_priority;

net/core/sock.c

@@ -1611,6 +1611,7 @@ void sock_init_data(struct socket *sock, struct sock *sk)
 	sk->sk_stamp = ktime_set(-1L, -1L);
 
 	atomic_set(&sk->sk_refcnt, 1);
+	atomic_set(&sk->sk_drops, 0);
 }
 
 void fastcall lock_sock_nested(struct sock *sk, int subclass)

net/ipv4/raw.c

@@ -241,7 +241,7 @@ static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
 	/* Charge it to the socket. */
 
 	if (sock_queue_rcv_skb(sk, skb) < 0) {
-		/* FIXME: increment a raw drops counter here */
+		atomic_inc(&sk->sk_drops);
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}
@@ -252,6 +252,7 @@ static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
 int raw_rcv(struct sock *sk, struct sk_buff *skb)
 {
 	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
+		atomic_inc(&sk->sk_drops);
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}
@@ -871,28 +872,30 @@ static __inline__ char *get_raw_sock(struct sock *sp, char *tmpbuf, int i)
 	      srcp  = inet->num;
 
 	sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X"
-		" %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p",
+		" %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %d",
 		i, src, srcp, dest, destp, sp->sk_state,
 		atomic_read(&sp->sk_wmem_alloc),
 		atomic_read(&sp->sk_rmem_alloc),
 		0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
-		atomic_read(&sp->sk_refcnt), sp);
+		atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops));
 	return tmpbuf;
 }
 
+#define TMPSZ 128
+
 static int raw_seq_show(struct seq_file *seq, void *v)
 {
-	char tmpbuf[129];
+	char tmpbuf[TMPSZ+1];
 
 	if (v == SEQ_START_TOKEN)
-		seq_printf(seq, "%-127s\n",
+		seq_printf(seq, "%-*s\n", TMPSZ-1,
 			       "  sl  local_address rem_address   st tx_queue "
 			       "rx_queue tr tm->when retrnsmt   uid  timeout "
-			       "inode");
+			       "inode  drops");
 	else {
 		struct raw_iter_state *state = raw_seq_private(seq);
 
-		seq_printf(seq, "%-127s\n",
+		seq_printf(seq, "%-*s\n", TMPSZ-1,
 			   get_raw_sock(v, tmpbuf, state->bucket));
 	}
 	return 0;