diff --git a/lib/thread.c b/lib/thread.c
index 9de5f94..9c3ee82 100644
--- a/lib/thread.c
+++ b/lib/thread.c
@@ -1217,6 +1217,8 @@
 #endif /* HAVE_CLOCK_MONOTONIC */
 }
 
+struct thread *thread_current = NULL;
+
 /* We check thread consumed time. If the system has getrusage, we'll
    use that to get in-depth stats on the performance of the thread in addition
    to wall clock time stats from gettimeofday. */
@@ -1246,7 +1248,9 @@
   GETRUSAGE (&before);
   thread->real = before.real;
 
+  thread_current = thread;
   (*thread->func) (thread);
+  thread_current = NULL;
 
   GETRUSAGE (&after);