X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Ftests%2Fthreads%2Falarm-priority.c;h=4839ecdfc81491d36c656ea4ef98761cf5206616;hb=e373cd64cfe799b3cb148e1117f3b3184b5a6457;hp=379f49213b136f1f7d53f87ddf176a17ea3ac37e;hpb=4ebf33908a571a7cde93fe618902b044e3633cdf;p=pintos-anon

diff --git a/src/tests/threads/alarm-priority.c b/src/tests/threads/alarm-priority.c
index 379f492..4839ecd 100644
--- a/src/tests/threads/alarm-priority.c
+++ b/src/tests/threads/alarm-priority.c
@@ -1,3 +1,6 @@
+/* Checks that when the alarm clock wakes up threads, the
+   higher-priority threads run first. */
+
 #include <stdio.h>
 #include "tests/threads/tests.h"
 #include "threads/init.h"
@@ -23,13 +26,13 @@ test_alarm_priority (void)
   
   for (i = 0; i < 10; i++) 
     {
-      int priority = (i + 5) % 10 + PRI_DEFAULT + 1;
+      int priority = PRI_DEFAULT - (i + 5) % 10 - 1;
       char name[16];
       snprintf (name, sizeof name, "priority %d", priority);
       thread_create (name, priority, alarm_priority_thread, NULL);
     }
 
-  thread_set_priority (PRI_MAX);
+  thread_set_priority (PRI_MIN);
 
   for (i = 0; i < 10; i++)
     sema_down (&wait_sema);
@@ -39,7 +42,7 @@ static void
 alarm_priority_thread (void *aux UNUSED) 
 {
   /* Busy-wait until the current time changes. */
-  int64_t start_time;
+  int64_t start_time = timer_ticks ();
   while (timer_elapsed (start_time) == 0)
     continue;