Looks like lockinit() was changed in 1.16 of sys/kern/kern_lock.c and the man page wasn't updated ;)
Index: lock.9 =================================================================== RCS file: /home/dcvs/src/share/man/man9/lock.9,v retrieving revision 1.4 diff -u -r1.4 lock.9 --- lock.9 23 Apr 2006 16:23:12 -0000 1.4 +++ lock.9 26 Jun 2006 22:09:37 -0000 @@ -41,7 +41,7 @@ .In sys/types.h .In sys/lock.h .Ft void -.Fn lockinit "struct lock *lkp" "int prio" "char *wmesg" "int timo" "int flags" +.Fn lockinit "struct lock *lkp" "char *wmesg" "int timo" "int flags" .Ft int .Fn lockcount "struct lock *lkp" .Ft int @@ -61,9 +61,6 @@ .Bl -tag -width ".Fa wmesg" .It Fa lkp A pointer to the lock to initialize. -.It Fa prio -The priority passed to -.Xr tsleep 9 . .It Fa wmesg The lock message. This is used for both debugging output and
