Add rm_wowned(9) function to test whether the current thread owns an

exclusive lock on the passed rmlock.

Reviewed by:	ups

share/man/man9/rmlock.9

@@ -26,8 +26,7 @@
 .\" $FreeBSD$
 .\"
 .\" Based on rwlock.9 man page
-
-.Dd August 22, 2007
+.Dd November 10, 2007
 .Dt RMLOCK 9
 .Os
 .Sh NAME
@@ -38,6 +37,7 @@
 .Nm rm_wlock ,
 .Nm rm_runlock ,
 .Nm rm_wunlock ,
+.Nm rm_wowned ,
 .Nm RM_SYSINIT
 .Nd mostly read lock - a kernel reader/writer lock optimized for mostly read access patterns
 .Sh SYNOPSIS
@@ -56,6 +56,8 @@
 .Fn rm_runlock "struct rmlock *rm" "struct rm_priotracker* tracker"
 .Ft void
 .Fn rm_wunlock "struct rmlock *rm"
+.Ft int
+.Fn rm_wowned "struct rmlock *rm"
 .In sys/kernel.h
 .Fn RM_SYSINIT "name" "struct rmlock *rm" "const char *desc" "int opts"
 .Sh DESCRIPTION
@@ -162,6 +164,10 @@ This functions destroys a lock previously initialized with
 The
 .Fa rm
 lock must be unlocked.
+.It Fn rm_wowned "struct rmlock *rm"
+This function returns a non-zero value if the current thread owns an
+exclusive lock on
+.Fa rm .
 .El
 .El
 .Sh SEE ALSO

sys/kern/kern_rmlock.c

@@ -175,6 +175,13 @@ rm_destroy(struct rmlock *rm)
 	lock_destroy(&rm->lock_object);
 }
 
+int
+rm_wowned(struct rmlock *rm)
+{
+
+	return (mtx_owned(&rm->rm_lock));
+}
+
 void
 rm_sysinit(void *arg)
 {

sys/sys/rmlock.h

@@ -42,6 +42,7 @@
 
 void	rm_init(struct rmlock *rm, const char *name, int opts);
 void	rm_destroy(struct rmlock *rm);
+int	rm_wowned(struct rmlock *rm);
 void	rm_sysinit(void *arg);