md spinlock

2 files changed, 16 insertions, 10 deletions

diff --git a/lib/libpthread/arch/alpha/_atomic_lock.c b/lib/libpthread/arch/alpha/_atomic_lock.c
index b12bc32d94a..75aace9532c 100644
--- a/lib/libpthread/arch/alpha/_atomic_lock.c
+++ b/lib/libpthread/arch/alpha/_atomic_lock.c
@@ -1,42 +1,42 @@
-/*	$OpenBSD: _atomic_lock.c,v 1.2 1998/12/18 05:59:17 d Exp $	*/
+/*	$OpenBSD: _atomic_lock.c,v 1.3 1998/12/21 07:36:59 d Exp $	*/
 /*
  * Atomic lock for alpha
  */
 
 #include "spinlock.h"
 
-register_t
-_atomic_lock(volatile register_t * lock)
+int
+_atomic_lock(volatile _spinlock_lock_t * lock)
 {
-	register_t old;
-	register_t new;
+	_spinlock_lock_t old;
+	_spinlock_lock_t new;
 	int success;
 
 	do {
 		/* load the value of the thread-lock (lock mem on load) */
 		__asm__( "ldq_l %0, %1" : "=r"(old) : "m"(*lock) );
 		if (old) 
-			new = old;	/* in-use: put it back */
+			new = old;	/* locked: no change */
 		else
-			new = 1;	/* free: store a 1 in the lock */
+			new = _SPINLOCK_LOCKED;	/* unlocked: grab it */
 
 		success = 0;
 		/* store the new value of the thrd-lock (unlock mem on store) */
 		/*
 		 * XXX may need to add large branch forward for main line
-		 * branch prediction to be right :(
+		 * branch prediction to be right :( [note from linux]
 		 */
 		__asm__( "stq_c %2, %0; beq %2, 1f; mov 1,%1; 1:"
 					: "=m"(*lock), "=r"(success)
 					: "r"(new) );
 	} while (!success);
 
-	return old;
+	return (old != _SPINLOCK_UNLOCKED);
 }
 
 int
 _atomic_is_locked(volatile register_t * lock)
 {
 	
-	return *lock;
+	return (*lock != _SPINLOCK_UNLOCKED);
 }
diff --git a/lib/libpthread/arch/alpha/_spinlock.h b/lib/libpthread/arch/alpha/_spinlock.h
new file mode 100644
index 00000000000..259260c28a0
--- /dev/null
+++ b/lib/libpthread/arch/alpha/_spinlock.h
@@ -0,0 +1,6 @@
+/*	$OpenBSD: _spinlock.h,v 1.1 1998/12/21 07:36:59 d Exp $	*/
+
+#define _SPINLOCK_UNLOCKED	(0)
+#define _SPINLOCK_LOCKED	(1)
+typedef int _spinlock_lock_t;
+