patch-2.1.16 linux/include/asm-ppc/semaphore.h

• Lines: 40
• Date: Wed Dec 18 10:54:10 1996
• Orig file: v2.1.15/linux/include/asm-ppc/semaphore.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v2.1.15/linux/include/asm-ppc/semaphore.h linux/include/asm-ppc/semaphore.h
@@ -0,0 +1,39 @@
+#ifndef _PPC_SEMAPHORE_H
+#define _PPC_SEMAPHORE_H
+
+#include <asm/atomic.h>
+
+struct semaphore {
+	atomic_t count;
+	atomic_t waiting;
+	struct wait_queue * wait;
+};
+
+#define MUTEX ((struct semaphore) { 1, 0, NULL })
+#define MUTEX_LOCKED ((struct semaphore) { 0, 0, NULL })
+
+extern void __down(struct semaphore * sem);
+extern void __up(struct semaphore * sem);
+
+extern void atomic_add(int c, int *v);
+extern void atomic_sub(int c, int *v);
+
+extern inline void down(struct semaphore * sem)
+{
+  for (;;)
+  {
+    atomic_dec_return(&sem->count);
+    if ( sem->count >= 0)
+      break;
+    __down(sem);
+  }
+}
+
+extern inline void up(struct semaphore * sem)
+{
+  atomic_inc_return(&sem->count);
+  if ( sem->count <= 0)
+    __up(sem);
+}	
+
+#endif /* !(_PPC_SEMAPHORE_H) */