Enhanced mbuf/pool diagnostics patch - puts the caller of m_free
into the pool history, rather than just the generic locations.

Index: sys/mbuf.h
===================================================================
RCS file: /cvs/src/sys/sys/mbuf.h,v
retrieving revision 1.77
diff -u -r1.77 mbuf.h
@@ -344,6 +346,25 @@
 	MCLINITREFERENCE(m); \
 } while (/* CONSTCOND */ 0)
 
+#ifdef POOL_DIAGNOSTIC
+#define	_MEXTREMOVE(m, f, l) do { \
+	if (MCLISREFERENCED(m)) { \
+		_MCLDEREFERENCE(m); \
+	} else if ((m)->m_flags & M_CLUSTER) { \
+		_pool_put(&mclpool, (m)->m_ext.ext_buf, f, l); \
+	} else if ((m)->m_ext.ext_free) { \
+		(*((m)->m_ext.ext_free))((m)->m_ext.ext_buf, \
+		    (m)->m_ext.ext_size, (m)->m_ext.ext_arg); \
+	} else { \
+		free((m)->m_ext.ext_buf,(m)->m_ext.ext_type); \
+	} \
+	(m)->m_flags &= ~(M_CLUSTER|M_EXT); \
+	(m)->m_ext.ext_size = 0;	/* why ??? */ \
+} while (/* CONSTCOND */ 0)
+
+#define	MEXTREMOVE(m) \
+	MBUFLOCK(_MEXTREMOVE((m), __FILE__, __LINE__);)
+#else
 #define	_MEXTREMOVE(m) do { \
 	if (MCLISREFERENCED(m)) { \
 		_MCLDEREFERENCE(m); \
@@ -361,6 +382,7 @@
 
 #define	MEXTREMOVE(m) \
 	MBUFLOCK(_MEXTREMOVE((m));)
+#endif
 
 /*
  * Reset the data pointer on an mbuf.
@@ -387,6 +409,23 @@
  * Free a single mbuf and associated external storage.
  * Place the successor, if any, in n.
  */
+#ifdef POOL_DIAGNOSTIC
+#define	MMFREE(m, n, f, l) \
+	MBUFLOCK( \
+		mbstat.m_mtypes[(m)->m_type]--; \
+		if ((m)->m_flags & M_PKTHDR) \
+			m_tag_delete_chain((m), NULL); \
+		if ((m)->m_flags & M_EXT) { \
+			_MEXTREMOVE((m), f, l); \
+		} \
+		(n) = (m)->m_next; \
+		_pool_put(&mbpool, (m), f, l); \
+	)
+
+#define	MFREE(m, n)	MMFREE(m, n, __FILE__, __LINE__)
+#define m_free(m)	mm_free(m, __FILE__, __LINE__)
+#define m_freem(m)	mm_freem(m, __FILE__, __LINE__)
+#else
 #define	MFREE(m, n) \
 	MBUFLOCK( \
 		mbstat.m_mtypes[(m)->m_type]--; \
@@ -398,6 +437,7 @@
 		(n) = (m)->m_next; \
 		pool_put(&mbpool, (m)); \
 	)
+#endif
 
 /*
  * Move just m_pkthdr from from to to,
@@ -544,7 +584,11 @@
 void	mbinit(void);
 struct	mbuf *m_copym2(struct mbuf *, int, int, int);
 struct	mbuf *m_copym(struct mbuf *, int, int, int);
+#ifdef POOL_DIAGNOSTIC
+struct	mbuf *mm_free(struct mbuf *, char *, int);
+#else
 struct	mbuf *m_free(struct mbuf *);
+#endif
 struct	mbuf *m_get(int, int);
 struct	mbuf *m_getclr(int, int);
 struct	mbuf *m_gethdr(int, int);
@@ -558,7 +602,11 @@
 void	m_adj(struct mbuf *, int);
 int	m_clalloc(int, int);
 void	m_copyback(struct mbuf *, int, int, const void *);
+#ifdef POOL_DIAGNOSTIC
+void	mm_freem(struct mbuf *, char *, int);
+#else
 void	m_freem(struct mbuf *);
+#endif
 void	m_reclaim(void *, int);
 void	m_copydata(struct mbuf *, int, int, caddr_t);
 void	m_cat(struct mbuf *, struct mbuf *);
Index: kern/uipc_mbuf.c
===================================================================
RCS file: /cvs/src/sys/kern/uipc_mbuf.c,v
retrieving revision 1.70
diff -u -r1.70 uipc_mbuf.c
--- kern/uipc_mbuf.c	27 May 2004 04:55:28 -0000	1.70
+++ kern/uipc_mbuf.c	7 Dec 2004 07:34:57 -0000
@@ -194,6 +194,34 @@
 	return (m);
 }
 
+#ifdef POOL_DIAGNOSTIC
+struct mbuf *
+mm_free(m, f, l)
+	struct mbuf *m;
+	char *f;
+	int l;
+{
+	register struct mbuf *n;
+
+	MMFREE(m, n, f, l);
+	return (n);
+}
+
+void
+mm_freem(m, f, l)
+	register struct mbuf *m;
+	char *f;
+	int l;
+{
+	register struct mbuf *n;
+
+	if (m == NULL)
+		return;
+	do {
+		MMFREE(m, n, f, l);
+	} while ((m = n) != NULL);
+}
+#else
 struct mbuf *
 m_free(m)
 	struct mbuf *m;
@@ -216,6 +244,7 @@
 		MFREE(m, n);
 	} while ((m = n) != NULL);
 }
+#endif
 
 /*
  * Mbuffer utility routines.