1 files changed, 60 insertions, 0 deletions

diff --git a/tests/threads/mlfqs-load-1.c b/tests/threads/mlfqs-load-1.c
new file mode 100644
index 0000000..a39eea2
--- /dev/null
+++ b/tests/threads/mlfqs-load-1.c
@@ -0,0 +1,60 @@
+/* Verifies that a single busy thread raises the load average to
+   0.5 in 38 to 45 seconds.  The expected time is 42 seconds, as
+   you can verify:
+   perl -e '$i++,$a=(59*$a+1)/60while$a<=.5;print "$i\n"'
+
+   Then, verifies that 10 seconds of inactivity drop the load
+   average back below 0.5 again. */
+
+#include <stdio.h>
+#include "tests/threads/tests.h"
+#include "threads/init.h"
+#include "threads/malloc.h"
+#include "threads/synch.h"
+#include "threads/thread.h"
+#include "devices/timer.h"
+
+void
+test_mlfqs_load_1 (void) 
+{
+  int64_t start_time;
+  int elapsed;
+  int load_avg;
+  
+  ASSERT (thread_mlfqs);
+
+  msg ("spinning for up to 45 seconds, please wait...");
+
+  start_time = timer_ticks ();
+  for (;;) 
+    {
+      load_avg = thread_get_load_avg ();
+      ASSERT (load_avg >= 0);
+      elapsed = timer_elapsed (start_time) / TIMER_FREQ;
+      if (load_avg > 100)
+        fail ("load average is %d.%02d "
+              "but should be between 0 and 1 (after %d seconds)",
+              load_avg / 100, load_avg % 100, elapsed);
+      else if (load_avg > 50)
+        break;
+      else if (elapsed > 45)
+        fail ("load average stayed below 0.5 for more than 45 seconds");
+    }
+
+  if (elapsed < 38)
+    fail ("load average took only %d seconds to rise above 0.5", elapsed);
+  msg ("load average rose to 0.5 after %d seconds", elapsed);
+
+  msg ("sleeping for another 10 seconds, please wait...");
+  timer_sleep (TIMER_FREQ * 10);
+
+  load_avg = thread_get_load_avg ();
+  if (load_avg < 0)
+    fail ("load average fell below 0");
+  if (load_avg > 50)
+    fail ("load average stayed above 0.5 for more than 10 seconds");
+  msg ("load average fell back below 0.5 (to %d.%02d)",
+       load_avg / 100, load_avg % 100);
+
+  pass ();
+}