[RFC PATCH 4/5] skb: add tracepoints to freeing skb

[Koki Sanagi <sanagi.koki@jp.fujitsu.com>]

This patch adds tracepoint to consume_skb and dev_kfree_skb_irq.

Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
---
 include/trace/events/skb.h |   36 ++++++++++++++++++++++++++++++++++++
 net/core/dev.c             |    2 ++
 net/core/skbuff.c          |    1 +
 3 files changed, 39 insertions(+), 0 deletions(-)

diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index 4b2be6d..6ab5b34 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -35,6 +35,42 @@ TRACE_EVENT(kfree_skb,
 		__entry->skbaddr, __entry->protocol, __entry->location)
 );
 
+TRACE_EVENT(consume_skb,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb),
+
+	TP_STRUCT__entry(
+		__field(	void *,	skbaddr	)
+	),
+
+	TP_fast_assign(
+		__entry->skbaddr = skb;
+	),
+
+	TP_printk("skbaddr=%p",
+		__entry->skbaddr)
+);
+
+TRACE_EVENT(dev_kfree_skb_irq,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb),
+
+	TP_STRUCT__entry(
+		__field(	void *,	skbaddr	)
+	),
+
+	TP_fast_assign(
+		__entry->skbaddr = skb;
+	),
+
+	TP_printk("skbaddr=%p",
+		__entry->skbaddr)
+);
+
 TRACE_EVENT(skb_copy_datagram_iovec,
 
 	TP_PROTO(const struct sk_buff *skb, int len),
diff --git a/net/core/dev.c b/net/core/dev.c
index f7c731b..e0093c4 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -131,6 +131,7 @@
 #include <linux/random.h>
 #include <trace/events/napi.h>
 #include <trace/events/net.h>
+#include <trace/events/skb.h>
 #include <linux/pci.h>
 
 #include "net-sysfs.h"
@@ -1584,6 +1585,7 @@ void dev_kfree_skb_irq(struct sk_buff *skb)
 		struct softnet_data *sd;
 		unsigned long flags;
 
+		trace_dev_kfree_skb_irq(skb);
 		local_irq_save(flags);
 		sd = &__get_cpu_var(softnet_data);
 		skb->next = sd->completion_queue;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 4e7ac09..008c019 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -466,6 +466,7 @@ void consume_skb(struct sk_buff *skb)
 		smp_rmb();
 	else if (likely(!atomic_dec_and_test(&skb->users)))
 		return;
+	trace_consume_skb(skb);
 	__kfree_skb(skb);
 }
 EXPORT_SYMBOL(consume_skb);