Locking primitives and operations in libthr should use struct umtx,

not spinlock_t. Spinlock_t and the associated functions and macros may
require blocking signals in order for async-safe libc functions to behave
appropriately in libthr. This is undesriable for libthr internal locking.
So, this is the first step in completely separating libthr from libc's
locking primitives.

Three new macros should be used for internal libthr locking from now on:
THR_LOCK, THR_TRYLOCK, THR_UNLOCK.

2 files changed, 22 insertions, 4 deletions

diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h
index 5e8da18..dd5f543 100644
--- a/lib/libthr/thread/thr_private.h
+++ b/lib/libthr/thread/thr_private.h
@@ -81,6 +81,24 @@
 #define	curthread	_get_curthread()
 
 /*
+ * Locking macros
+ */
+#define	THR_LOCK(m)							\
+	do {								\
+		if (umtx_lock((m), curthread->thr_id) != 0)		\
+			abort();					\
+	} while (0)
+
+#define THR_TRYLOCK(m)		_umtxtrylock((m))
+
+#define	THR_UNLOCK(m)							\
+	do {								\
+		if (umtx_unlock((m), curthread->thr_id) != 0)		\
+			abort();					\
+	} while (0)
+
+
+/*
  * State change macro without scheduling queue change:
  */
 #define PTHREAD_SET_STATE(thrd, newstate) do {				\
@@ -431,7 +449,7 @@ struct pthread {
 	/*
 	 * Lock for accesses to this thread structure.
 	 */
-	spinlock_t		lock;
+	struct umtx		lock;
 
 	/* Queue entry for list of all threads: */
 	TAILQ_ENTRY(pthread)	tle;
@@ -748,7 +766,6 @@ int	_pthread_mutexattr_settype(pthread_mutexattr_t *, int);
 int	_pthread_once(pthread_once_t *, void (*) (void));
 pthread_t _pthread_self(void);
 int	_pthread_setspecific(pthread_key_t, const void *);
-int	_spintrylock(spinlock_t *);
 void    _thread_exit(char *, int, char *);
 void    _thread_exit_cleanup(void);
 void    *_thread_cleanup(pthread_t);
@@ -768,6 +785,7 @@ void	_thread_critical_enter(pthread_t);
 void	_thread_critical_exit(pthread_t);
 void	_thread_sigblock();
 void	_thread_sigunblock();
+int	_umtxtrylock(struct umtx *lck);
 
 /* #include <sys/aio.h> */
 #ifdef _SYS_AIO_H_
diff --git a/lib/libthr/thread/thr_spinlock.c b/lib/libthr/thread/thr_spinlock.c
index 53e9851..dcb6fac 100644
--- a/lib/libthr/thread/thr_spinlock.c
+++ b/lib/libthr/thread/thr_spinlock.c
@@ -65,10 +65,10 @@ _spinlock(spinlock_t *lck)
 }
 
 int
-_spintrylock(spinlock_t *lck)
+_umtxtrylock(struct umtx *lck)
 {
 	int error;
-	error = umtx_trylock((struct umtx *)lck, curthread->thr_id);
+	error = umtx_trylock(lck, curthread->thr_id);
 	if (error != 0 && error != EBUSY)
 		abort();
 	return (error);