From 2f5b1d1570111e50c4639380cdc0d731decf8f67 Mon Sep 17 00:00:00 2001
From: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Date: Tue, 5 May 2015 15:09:59 +0300
Subject: [PATCH] net: Add a way to see who is trying to alloc/dealloc a
 net_buf

Change-Id: Ib7813bc5809f85f27aa4fe06583b64461741466a
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
---
 include/net/net_buf.h | 23 +++++++++++++++++++++++
 net/ip/net_buf.c      | 24 ++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/include/net/net_buf.h b/include/net/net_buf.h
index 489eae0e647..c1ac84e2ca1 100644
--- a/include/net/net_buf.h
+++ b/include/net/net_buf.h
@@ -46,6 +46,11 @@
 #include "contiki/ip/uip.h"
 #include "contiki/packetbuf.h"
 
+#if defined(CONFIG_NETWORKING_WITH_LOGGING)
+#undef DEBUG_NET_BUFS
+#define DEBUG_NET_BUFS
+#endif
+
 struct net_context;
 
 /*! The default MTU is 1280 (minimum IPv6 packet size) + LL header
@@ -172,7 +177,13 @@ struct net_buf {
  *
  * @return Network buffer if successful, NULL otherwise.
  */
+/* Get buffer from the available buffers pool */
+#ifdef DEBUG_NET_BUFS
+#define net_buf_get(context) net_buf_get_debug(context, __FUNCTION__, __LINE__)
+struct net_buf *net_buf_get_debug(struct net_context *context, const char *caller, int line);
+#else
 struct net_buf *net_buf_get(struct net_context *context);
+#endif
 
 /*!
  * @brief Get buffer from pool but also reserve headroom for
@@ -185,7 +196,13 @@ struct net_buf *net_buf_get(struct net_context *context);
  *
  * @return Network buffer if successful, NULL otherwise.
  */
+/* Same as net_buf_get, but also reserve headroom for potential headers */
+#ifdef DEBUG_NET_BUFS
+#define net_buf_get_reserve(res) net_buf_get_reserve_debug(res,__FUNCTION__,__LINE__)
+struct net_buf *net_buf_get_reserve_debug(uint16_t reserve_head, const char *caller, int line);
+#else
 struct net_buf *net_buf_get_reserve(uint16_t reserve_head);
+#endif
 
 /*!
  * @brief Place buffer back into the available buffers pool.
@@ -197,7 +214,13 @@ struct net_buf *net_buf_get_reserve(uint16_t reserve_head);
  * @param buf Network buffer to release.
  *
  */
+/* Place buffer back into the available buffers pool */
+#ifdef DEBUG_NET_BUFS
+#define net_buf_put(buf) net_buf_put_debug(buf, __FUNCTION__, __LINE__)
+void net_buf_put_debug(struct net_buf *buf, const char *caller, int line);
+#else
 void net_buf_put(struct net_buf *buf);
+#endif
 
 /*!
  * @brief Prepare data to be added at the end of the buffer.
diff --git a/net/ip/net_buf.c b/net/ip/net_buf.c
index 7d1da9f7510..db1944f4c04 100644
--- a/net/ip/net_buf.c
+++ b/net/ip/net_buf.c
@@ -53,13 +53,21 @@ extern struct net_tuple *net_context_get_tuple(struct net_context *context);
 static struct net_buf		buffers[NUM_BUFS];
 static struct nano_fifo		free_bufs;
 
+#ifdef DEBUG_NET_BUFS
+struct net_buf *net_buf_get_reserve_debug(uint16_t reserve_head, const char *caller, int line)
+#else
 struct net_buf *net_buf_get_reserve(uint16_t reserve_head)
+#endif
 {
 	struct net_buf *buf;
 
 	buf = nano_fifo_get(&free_bufs);
 	if (!buf) {
+#ifdef DEBUG_NET_BUFS
+		NET_ERR("Failed to get free buffer (%s():%d)\n", caller, line);
+#else
 		NET_ERR("Failed to get free buffer\n");
+#endif
 		return NULL;
 	}
 
@@ -71,7 +79,11 @@ struct net_buf *net_buf_get_reserve(uint16_t reserve_head)
 	return buf;
 }
 
+#ifdef DEBUG_NET_BUFS
+struct net_buf *net_buf_get_debug(struct net_context *context, const char *caller, int line)
+#else
 struct net_buf *net_buf_get(struct net_context *context)
+#endif
 {
 	struct net_buf *buf;
 	struct net_tuple *tuple;
@@ -94,7 +106,11 @@ struct net_buf *net_buf_get(struct net_context *context)
 		break;
 	}
 
+#ifdef DEBUG_NET_BUFS
+	buf = net_buf_get_reserve_debug(reserve, caller, line);
+#else
 	buf = net_buf_get_reserve(reserve);
+#endif
 	if (!buf) {
 		return buf;
 	}
@@ -104,9 +120,17 @@ struct net_buf *net_buf_get(struct net_context *context)
 	return buf;
 }
 
+#ifdef DEBUG_NET_BUFS
+void net_buf_put_debug(struct net_buf *buf, const char *caller, int line)
+#else
 void net_buf_put(struct net_buf *buf)
+#endif
 {
+#ifdef DEBUG_NET_BUFS
+	NET_DBG("buf %p (%s():%d)\n", buf, caller, line);
+#else
 	NET_DBG("buf %p\n", buf);
+#endif
 
 	nano_fifo_put(&free_bufs, buf);
 }