PERFORCE change 95271 for review

[John Birrell]

http://perforce.freebsd.org/chv.cgi?CH=95271

Change 95271 by jb at jb_freebsd2 on 2006/04/14 21:26:28

	Add some experimental (non-POSIX, non-portable) thread functions to
	check if a mutex or a rwlock is held. Solaris has these in it's
	non-standard thread implementation and they've implemented DTrace
	mostly using the non-standard threads, but with some pthreads
	thrown in... and to make matters worse, even non-POSIX pthread
	functions. Yuk. Solaris may well be standards compatible from an
	outside programmer's perspective, but it sure as hell isn't on the
	inside.

Affected files ...

.. //depot/projects/dtrace/src/include/pthread_np.h#2 edit
.. //depot/projects/dtrace/src/lib/libpthread/pthread.map#2 edit
.. //depot/projects/dtrace/src/lib/libpthread/thread/thr_mutex.c#2 edit
.. //depot/projects/dtrace/src/lib/libpthread/thread/thr_rwlock.c#2 edit

Differences ...

==== //depot/projects/dtrace/src/include/pthread_np.h#2 (text+ko) ====

@@ -49,8 +49,11 @@
 int pthread_multi_np(void);
 int pthread_mutexattr_getkind_np(pthread_mutexattr_t);
 int pthread_mutexattr_setkind_np(pthread_mutexattr_t *, int);
+int pthread_mutex_held_np(pthread_mutex_t *);
 void pthread_resume_all_np(void);
 int pthread_resume_np(pthread_t);
+int pthread_rwlock_rdheld_np(pthread_rwlock_t *);
+int pthread_rwlock_wrheld_np(pthread_rwlock_t *);
 void pthread_set_name_np(pthread_t, const char *);
 int pthread_single_np(void);
 void pthread_suspend_all_np(void);

==== //depot/projects/dtrace/src/lib/libpthread/pthread.map#2 (text+ko) ====

@@ -258,6 +258,7 @@
 	pthread_multi_np;
 	pthread_mutex_destroy;
 	pthread_mutex_getprioceiling;
+	pthread_mutex_held_np;
 	pthread_mutex_init;
 	pthread_mutex_lock;
 	pthread_mutex_setprioceiling;
@@ -280,6 +281,8 @@
 	pthread_resume_all_np;
 	pthread_resume_np;
 	pthread_rwlock_destroy;
+	pthread_rwlock_rdheld_np;
+	pthread_rwlock_wrheld_np;
 	pthread_rwlock_init;
 	pthread_rwlock_rdlock;
 	pthread_rwlock_timedrdlock;

==== //depot/projects/dtrace/src/lib/libpthread/thread/thr_mutex.c#2 (text+ko) ====

@@ -1582,6 +1582,12 @@
 	}
 }
 
+int
+pthread_mutex_held_np(pthread_mutex_t *m)
+{
+	return((*m)->m_owner == _get_curthread());
+}
+
 /*
  * This is called by the current thread when it wants to back out of a
  * mutex_lock in order to run a signal handler.

==== //depot/projects/dtrace/src/lib/libpthread/thread/thr_rwlock.c#2 (text+ko) ====

@@ -436,3 +436,15 @@
 {
 	return (rwlock_wrlock_common (rwlock, abstime));
 }
+
+int
+pthread_rwlock_rdheld_np(pthread_rwlock_t *rwlock)
+{
+	return((*rwlock)->state > 0);
+}
+
+int
+pthread_rwlock_wrheld_np(pthread_rwlock_t *rwlock)
+{
+	return((*rwlock)->state < 0);
+}