X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?p=pintos-anon;a=blobdiff_plain;f=src%2Fthreads%2Fsynch.h;h=53a5ee488cf07c83f68a7b136bc6506136180ac9;hp=c13f95d8d429a762843824e8c4e70fc1f6d4a799;hb=615bf3b3d2a8573ed6fb9ddc0055745e163ac999;hpb=5780c9f434cca090f88463b7f0199d49b4ded288

diff --git a/src/threads/synch.h b/src/threads/synch.h
index c13f95d..53a5ee4 100644
--- 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 *name);
+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 +24,27 @@ struct lock
     struct semaphore semaphore; /* Binary semaphore controlling access. */
   };
 
-void lock_init (struct lock *, const char *name);
+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 *name);
+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 *);
+
+/* Memory barrier.
+
+   The compiler will not reorder operations that access memory
+   across a memory barrier. */
+#define barrier() asm volatile ("")
 
 #endif /* threads/synch.h */