net: add location to trace_consume_skb()

kfree_skb() includes the location, it makes sense
to add it to consume_skb() as well.

After patch:

 taskd_EventMana  8602 [004]   420.406239: skb:consume_skb: skbaddr=0xffff893a4a6d0500 location=unix_stream_read_generic
         swapper     0 [011]   422.732607: skb:consume_skb: skbaddr=0xffff89597f68cee0 location=mlx4_en_free_tx_desc
      discipline  9141 [043]   423.065653: skb:consume_skb: skbaddr=0xffff893a487e9c00 location=skb_consume_udp
         swapper     0 [010]   423.073166: skb:consume_skb: skbaddr=0xffff8949ce9cdb00 location=icmpv6_rcv
         borglet  8672 [014]   425.628256: skb:consume_skb: skbaddr=0xffff8949c42e9400 location=netlink_dump
         swapper     0 [028]   426.263317: skb:consume_skb: skbaddr=0xffff893b1589dce0 location=net_rx_action
            wget 14339 [009]   426.686380: skb:consume_skb: skbaddr=0xffff893a51b552e0 location=tcp_rcv_state_process
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/trace/events/skb.h

@@ -53,19 +53,21 @@ TRACE_EVENT(kfree_skb,
 
 TRACE_EVENT(consume_skb,
 
-	TP_PROTO(struct sk_buff *skb),
+	TP_PROTO(struct sk_buff *skb, void *location),
 
-	TP_ARGS(skb),
+	TP_ARGS(skb, location),
 
 	TP_STRUCT__entry(
-		__field(	void *,	skbaddr	)
+		__field(	void *,	skbaddr)
+		__field(	void *,	location)
 	),
 
 	TP_fast_assign(
 		__entry->skbaddr = skb;
+		__entry->location = location;
 	),
 
-	TP_printk("skbaddr=%p", __entry->skbaddr)
+	TP_printk("skbaddr=%p location=%pS", __entry->skbaddr, __entry->location)
 );
 
 TRACE_EVENT(skb_copy_datagram_iovec,

net/core/dev.c

@@ -5019,7 +5019,7 @@ static __latent_entropy void net_tx_action(struct softirq_action *h)
 
 			WARN_ON(refcount_read(&skb->users));
 			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
-				trace_consume_skb(skb);
+				trace_consume_skb(skb, net_tx_action);
 			else
 				trace_kfree_skb(skb, net_tx_action,
 						SKB_DROP_REASON_NOT_SPECIFIED);

net/core/skbuff.c

@@ -991,7 +991,7 @@ bool __kfree_skb_reason(struct sk_buff *skb, enum skb_drop_reason reason)
 	DEBUG_NET_WARN_ON_ONCE(reason <= 0 || reason >= SKB_DROP_REASON_MAX);
 
 	if (reason == SKB_CONSUMED)
-		trace_consume_skb(skb);
+		trace_consume_skb(skb, __builtin_return_address(0));
 	else
 		trace_kfree_skb(skb, __builtin_return_address(0), reason);
 	return true;
@@ -1189,7 +1189,7 @@ void consume_skb(struct sk_buff *skb)
 	if (!skb_unref(skb))
 		return;
 
-	trace_consume_skb(skb);
+	trace_consume_skb(skb, __builtin_return_address(0));
 	__kfree_skb(skb);
 }
 EXPORT_SYMBOL(consume_skb);
@@ -1204,7 +1204,7 @@ EXPORT_SYMBOL(consume_skb);
  */
 void __consume_stateless_skb(struct sk_buff *skb)
 {
-	trace_consume_skb(skb);
+	trace_consume_skb(skb, __builtin_return_address(0));
 	skb_release_data(skb, SKB_CONSUMED);
 	kfree_skbmem(skb);
 }
@@ -1260,7 +1260,7 @@ void napi_consume_skb(struct sk_buff *skb, int budget)
 		return;
 
 	/* if reaching here SKB is ready to free */
-	trace_consume_skb(skb);
+	trace_consume_skb(skb, __builtin_return_address(0));
 
 	/* if SKB is a clone, don't handle this case */
 	if (skb->fclone != SKB_FCLONE_UNAVAILABLE) {