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[pintos-anon] / src / threads / synch.h

diff --git a/src/threads/synch.h b/src/threads/synch.h
index ad8423891bad260215a77d0274dddfd75c960962..a19e88b181dff1208839ff890154aa69b299ce91 100644 (file)
--- a/src/threads/synch.h
+++ b/src/threads/synch.h
@@ -7,15 +7,14 @@
 /* A counting semaphore. */
 struct semaphore 
   {
-    char name[16];              /* Name (for debugging purposes only). */
     unsigned value;             /* Current value. */
     struct list waiters;        /* List of waiting threads. */
   };
 
-void sema_init (struct semaphore *, unsigned value, const char *);
+void sema_init (struct semaphore *, unsigned value);
 void sema_down (struct semaphore *);
+bool sema_try_down (struct semaphore *);
 void sema_up (struct semaphore *);
-const char *sema_name (const struct semaphore *);
 void sema_self_test (void);
 
 /* Lock. */
@@ -25,23 +24,28 @@ struct lock
     struct semaphore semaphore; /* Binary semaphore controlling access. */
   };
 
-void lock_init (struct lock *, const char *);
+void lock_init (struct lock *);
 void lock_acquire (struct lock *);
+bool lock_try_acquire (struct lock *);
 void lock_release (struct lock *);
 bool lock_held_by_current_thread (const struct lock *);
-const char *lock_name (const struct lock *);
 
 /* Condition variable. */
 struct condition 
   {
-    char name[16];              /* Name (for debugging purposes only). */
     struct list waiters;        /* List of waiting threads. */
   };
 
-void cond_init (struct condition *, const char *);
+void cond_init (struct condition *);
 void cond_wait (struct condition *, struct lock *);
 void cond_signal (struct condition *, struct lock *);
 void cond_broadcast (struct condition *, struct lock *);
-const char *cond_name (const struct condition *);
+
+/* Optimization barrier.
+
+   The compiler will not reorder operations across an
+   optimization barrier.  See "Optimization Barriers" in the
+   reference guide for more information.*/
+#define barrier() asm volatile ("" : : : "memory")
 
 #endif /* threads/synch.h */