Index: share/dtrace/Makefile
===================================================================
--- share/dtrace/Makefile
+++ share/dtrace/Makefile
@@ -30,4 +30,10 @@
 
 SCRIPTSDIR= ${SHAREDIR}/dtrace
 
+DSRCS=		mbuf.d
+
+FILES=		${DSRCS}
+FILESDIR=	/usr/lib/dtrace
+FILESMODE=	${NOBINMODE}
+
 .include <bsd.prog.mk>
Index: sys/kern/kern_mbuf.c
===================================================================
--- sys/kern/kern_mbuf.c
+++ sys/kern/kern_mbuf.c
@@ -731,6 +731,7 @@
 		zone_drain(zone_pack);
 		uma_zalloc_arg(zone_clust, m, how);
 	}
+	MBUF_PROBE2(m__clget, m, how);
 	return (m->m_flags & M_EXT);
 }
 
@@ -746,6 +747,8 @@
 {
 	uma_zone_t zone;
 
+	MBUF_PROBE3(m__cljget, m, how, size);
+
 	if (m != NULL) {
 		KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT",
 		    __func__, m));
@@ -933,6 +936,7 @@
 void
 m_freem(struct mbuf *mb)
 {
+	MBUF_PROBE1(m__freem, mb);
 
 	while (mb != NULL)
 		mb = m_free(mb);
Index: sys/kern/uipc_mbuf.c
===================================================================
--- sys/kern/uipc_mbuf.c
+++ sys/kern/uipc_mbuf.c
@@ -47,6 +47,45 @@
 #include <sys/domain.h>
 #include <sys/protosw.h>
 #include <sys/uio.h>
+#include <sys/sdt.h>
+
+SDT_PROVIDER_DEFINE(mbuf);
+
+SDT_PROBE_DEFINE4_XLATE(mbuf, , , m__init,
+    "struct mbuf *", "mbufinfo_t *",
+    "uint32_t", "uint32_t",
+    "uint16_t", "uint16_t",
+    "uint32_t", "uint32_t");
+
+SDT_PROBE_DEFINE3_XLATE(mbuf, , , m__gethdr,
+    "uint32_t", "uint32_t",
+    "uint16_t", "uint16_t",
+    "struct mbuf *", "mbufinfo_t *");
+
+SDT_PROBE_DEFINE3_XLATE(mbuf, , , m__get,
+    "uint32_t", "uint32_t",
+    "uint16_t", "uint16_t",
+    "struct mbuf *", "mbufinfo_t *");
+
+SDT_PROBE_DEFINE4_XLATE(mbuf, , , m__getcl,
+    "uint32_t", "uint32_t",
+    "uint16_t", "uint16_t",
+    "uint32_t", "uint32_t",
+    "struct mbuf *", "mbufinfo_t *");
+
+SDT_PROBE_DEFINE3_XLATE(mbuf, , , m__clget,
+    "struct mbuf *", "mbufinfo_t *",
+    "uint32_t", "uint32_t",
+    "uint32_t", "uint32_t");
+
+SDT_PROBE_DEFINE(mbuf, , , m__cljget);
+SDT_PROBE_DEFINE(mbuf, , , m__cljset);
+
+SDT_PROBE_DEFINE1_XLATE(mbuf, , , m__free,
+        "struct mbuf *", "mbufinfo_t *");
+
+SDT_PROBE_DEFINE1_XLATE(mbuf, , , m__freem,
+    "struct mbuf *", "mbufinfo_t *");
 
 #include <security/mac/mac_framework.h>
 
Index: sys/sys/mbuf.h
===================================================================
--- sys/sys/mbuf.h
+++ sys/sys/mbuf.h
@@ -44,6 +44,32 @@
 #endif
 #endif
 
+#ifdef _KERNEL
+#include <sys/sdt.h>
+
+#define	MBUF_PROBE1(probe, arg0)					\
+	SDT_PROBE1(mbuf, , , probe, arg0)
+#define	MBUF_PROBE2(probe, arg0, arg1)					\
+	SDT_PROBE2(mbuf, , , probe, arg0, arg1)
+#define	MBUF_PROBE3(probe, arg0, arg1, arg2)			\
+	SDT_PROBE3(mbuf, , , probe, arg0, arg1, arg2)
+#define	MBUF_PROBE4(probe, arg0, arg1, arg2, arg3)				\
+	SDT_PROBE4(mbuf, , , probe, arg0, arg1, arg2, arg3)
+
+SDT_PROVIDER_DECLARE(mbuf);
+
+SDT_PROBE_DECLARE(mbuf, , , m__init);
+SDT_PROBE_DECLARE(mbuf, , , m__gethdr);
+SDT_PROBE_DECLARE(mbuf, , , m__get);
+SDT_PROBE_DECLARE(mbuf, , , m__getcl);
+SDT_PROBE_DECLARE(mbuf, , , m__clget);
+SDT_PROBE_DECLARE(mbuf, , , m__cljget);
+SDT_PROBE_DECLARE(mbuf, , , m__cljset);
+SDT_PROBE_DECLARE(mbuf, , , m__free);
+SDT_PROBE_DECLARE(mbuf, , , m__freem);
+
+#endif /* _KERNEL */
+
 /*
  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
@@ -666,6 +692,7 @@
 {
 	int error;
 
+	MBUF_PROBE4(m__init, m, how, type, flags);
 	m->m_next = NULL;
 	m->m_nextpkt = NULL;
 	m->m_data = m->m_dat;
@@ -683,31 +710,40 @@
 static __inline struct mbuf *
 m_get(int how, short type)
 {
+	struct mbuf *m;
 	struct mb_args args;
 
 	args.flags = 0;
 	args.type = type;
-	return (uma_zalloc_arg(zone_mbuf, &args, how));
+	m = uma_zalloc_arg(zone_mbuf, &args, how);
+	MBUF_PROBE3(m__get, how, type, m);
+	return (m);
 }
 
 static __inline struct mbuf *
 m_gethdr(int how, short type)
 {
+	struct mbuf *m;
 	struct mb_args args;
 
 	args.flags = M_PKTHDR;
 	args.type = type;
-	return (uma_zalloc_arg(zone_mbuf, &args, how));
+	m = uma_zalloc_arg(zone_mbuf, &args, how);
+	MBUF_PROBE3(m__gethdr, how, type, m);
+	return (m);
 }
 
 static __inline struct mbuf *
 m_getcl(int how, short type, int flags)
 {
+	struct mbuf *m;
 	struct mb_args args;
 
 	args.flags = flags;
 	args.type = type;
-	return (uma_zalloc_arg(zone_pack, &args, how));
+	m = uma_zalloc_arg(zone_pack, &args, how);
+	MBUF_PROBE4(m__getcl, how, type, flags, m);
+	return (m);
 }
 
 /*
@@ -720,6 +756,7 @@
 {
 	int size;
 
+	MBUF_PROBE3(m__cljset, m, cl, type);
 	switch (type) {
 	case EXT_CLUSTER:
 		size = MCLBYTES;
@@ -1122,6 +1159,7 @@
 {
 	struct mbuf *n = m->m_next;
 
+	MBUF_PROBE1(m__free, m);
 	if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
 		m_tag_delete_chain(m, NULL);
 	if (m->m_flags & M_EXT)