--- jsr166/src/test/tck/JSR166TestCase.java	2019/04/24 17:36:09	1.254
+++ jsr166/src/test/tck/JSR166TestCase.java	2019/09/05 17:27:07	1.260
@@ -288,8 +288,9 @@ public class JSR166TestCase extends Test
             // Avoid spurious reports with enormous runsPerTest.
             // A single test case run should never take more than 1 second.
             // But let's cap it at the high end too ...
-            final int timeoutMinutes =
-                Math.min(15, Math.max(runsPerTest / 60, 1));
+            final int timeoutMinutesMin = Math.max(runsPerTest / 60, 1)
+                * Math.max((int) delayFactor, 1);
+            final int timeoutMinutes = Math.min(15, timeoutMinutesMin);
             for (TestCase lastTestCase = currentTestCase;;) {
                 try { MINUTES.sleep(timeoutMinutes); }
                 catch (InterruptedException unexpected) { break; }
@@ -684,6 +685,20 @@ public class JSR166TestCase extends Test
     static TimeUnit randomTimeUnit() { return RANDOM_TIMEUNIT; }
 
     /**
+     * Returns a random boolean; a "coin flip".
+     */
+    static boolean randomBoolean() {
+        return ThreadLocalRandom.current().nextBoolean();
+    }
+
+    /**
+     * Returns a random element from given choices.
+     */
+    <T> T chooseRandomly(T... choices) {
+        return choices[ThreadLocalRandom.current().nextInt(choices.length)];
+    }
+
+    /**
      * Returns the shortest timed delay. This can be scaled up for
      * slow machines using the jsr166.delay.factor system property,
      * or via jtreg's -timeoutFactor: flag.
@@ -739,8 +754,8 @@ public class JSR166TestCase extends Test
      */
     public void threadRecordFailure(Throwable t) {
         System.err.println(t);
-        dumpTestThreads();
-        threadFailure.compareAndSet(null, t);
+        if (threadFailure.compareAndSet(null, t))
+            dumpTestThreads();
     }
 
     public void setUp() {
@@ -1366,6 +1381,20 @@ public class JSR166TestCase extends Test
     }
 
     /**
+     * Spin-waits up to LONG_DELAY_MS milliseconds for the current thread to
+     * be interrupted.  Clears the interrupt status before returning.
+     */
+    void awaitInterrupted() {
+        for (long startTime = 0L; !Thread.interrupted(); ) {
+            if (startTime == 0L)
+                startTime = System.nanoTime();
+            else if (millisElapsedSince(startTime) > LONG_DELAY_MS)
+                fail("timed out waiting for thread interrupt");
+            Thread.yield();
+        }
+    }
+
+    /**
      * Returns the number of milliseconds since time given by
      * startNanoTime, which must have been previously returned from a
      * call to {@link System#nanoTime()}.
@@ -1426,11 +1455,12 @@ public class JSR166TestCase extends Test
             t.join(timeoutMillis);
         } catch (InterruptedException fail) {
             threadUnexpectedException(fail);
-        } finally {
-            if (t.getState() != Thread.State.TERMINATED) {
-                t.interrupt();
-                threadFail("timed out waiting for thread to terminate");
-            }
+        }
+        Thread.State state;
+        if ((state = t.getState()) != Thread.State.TERMINATED) {
+            t.interrupt();
+            threadFail("timed out waiting for thread to terminate; "
+                       + "state=" + state);
         }
     }