=====================================================================
Add kern_lockstat.c.
---------------------------------------------------------------------
--- /u/freebsd/head/src/sys/conf/files	2008-05-21 07:25:51.000000000 +1000
+++ /u/p4/dtrace/src/sys/conf/files	2008-05-21 07:27:18.000000000 +1000
@@ -1632,6 +1632,7 @@
 kern/kern_linker.c		standard
 kern/kern_lock.c		standard
 kern/kern_lockf.c		standard
+kern/kern_lockstat.c		optional kdtrace_hooks
 kern/kern_malloc.c		standard
 kern/kern_mbuf.c		standard
 kern/kern_mib.c			standard
=====================================================================
lockstat support
---------------------------------------------------------------------
--- /u/freebsd/head/src/sys/sys/mutex.h	2008-05-17 11:54:42.000000000 +1000
+++ /u/p4/dtrace/src/sys/sys/mutex.h	2008-05-17 11:54:48.000000000 +1000
@@ -168,9 +168,11 @@
 	uintptr_t _tid = (uintptr_t)(tid);				\
 	if (!_obtain_lock((mp), _tid)) {				\
 		_mtx_lock_sleep((mp), _tid, (opts), (file), (line));	\
-	} else 								\
+	} else {							\
               	lock_profile_obtain_lock_success(&(mp)->lock_object, 0,	\
 		    0, (file), (line));					\
+		LOCKSTAT_RECORD0(LS_MTX_LOCK_ACQUIRE, mp);		\
+	}								\
 } while (0)
 #endif
 
@@ -192,9 +194,11 @@
 		else {							\
 			_mtx_lock_spin((mp), _tid, (opts), (file), (line)); \
 		}							\
-	} else 								\
+	} else {							\
               	lock_profile_obtain_lock_success(&(mp)->lock_object, 0,	\
 		    0, (file), (line));					\
+		LOCKSTAT_RECORD0(LS_MTX_SPIN_LOCK_ACQUIRE, mp);		\
+	}								\
 } while (0)
 #else /* SMP */
 #define _get_spin_lock(mp, tid, opts, file, line) do {			\
@@ -241,6 +245,7 @@
 		(mp)->mtx_recurse--;					\
 	else {								\
 		lock_profile_release_lock(&(mp)->lock_object);          \
+		LOCKSTAT_RECORD0(LS_MTX_SPIN_UNLOCK_RELEASE,  mp);	\
 		_release_lock_quick((mp));				\
 	}                                                               \
 	spinlock_exit();				                \
=====================================================================
lockstat support
---------------------------------------------------------------------
--- /u/freebsd/head/src/sys/sys/rwlock.h	2008-05-17 11:54:42.000000000 +1000
+++ /u/p4/dtrace/src/sys/sys/rwlock.h	2008-05-17 11:54:48.000000000 +1000
@@ -35,6 +35,7 @@
 #include <sys/_lock.h>
 #include <sys/_rwlock.h>
 #include <sys/lock_profile.h>
+#include <sys/lockstat.h>
 
 #ifdef _KERNEL
 #include <sys/pcpu.h>
@@ -107,9 +108,11 @@
 						                        \
 	if (!_rw_write_lock((rw), _tid))				\
 		_rw_wlock_hard((rw), _tid, (file), (line));		\
-	else								\
+	else {								\
 		lock_profile_obtain_lock_success(&(rw)->lock_object, 0,	\
 		    0, (file), (line));					\
+		LOCKSTAT_RECORD0(LS_RW_WLOCK_ACQUIRE, rw);		\
+	}								\
 } while (0)
 
 /* Release a write lock. */
=====================================================================
lockstat support
---------------------------------------------------------------------
--- /u/freebsd/head/src/sys/sys/sx.h	2007-12-16 10:13:31.000000000 +1100
+++ /u/p4/dtrace/src/sys/sys/sx.h	2008-04-19 17:11:35.000000000 +1000
@@ -35,6 +35,7 @@
 #include <sys/_lock.h>
 #include <sys/_sx.h>
 #include <sys/lock_profile.h>
+#include <sys/lockstat.h>
 
 #ifdef	_KERNEL
 #include <machine/atomic.h>
@@ -151,9 +152,11 @@
 
 	if (!atomic_cmpset_acq_ptr(&sx->sx_lock, SX_LOCK_UNLOCKED, tid))
 		error = _sx_xlock_hard(sx, tid, opts, file, line);
-	else
+	else {
 		lock_profile_obtain_lock_success(&sx->lock_object, 0, 0, file,
 		    line);
+		LOCKSTAT_RECORD0(LS_SX_XLOCK_ACQUIRE, sx);
+	}
 
 	return (error);
 }
@@ -178,9 +181,11 @@
 	if (!(x & SX_LOCK_SHARED) ||
 	    !atomic_cmpset_acq_ptr(&sx->sx_lock, x, x + SX_ONE_SHARER))
 		error = _sx_slock_hard(sx, opts, file, line);
-	else
+	else {
 		lock_profile_obtain_lock_success(&sx->lock_object, 0, 0, file,
 		    line);
+		LOCKSTAT_RECORD0(LS_SX_SLOCK_ACQUIRE, sx);
+	}
 
 	return (error);
 }