* ext/thread/thread.c (rb_szqueue_push): check GET_SZQUEUE_WAITERS

  instead of GET_QUEUE_WAITERS to prevent deadlock. Patch by Eric Wong.
  [Bug ruby#9302] [ruby-core:59324]

* test/thread/test_queue.rb: add test

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44583 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Author: Charlie Somerville

ext/thread/thread.c

@@ -459,7 +459,7 @@ static VALUE
 rb_szqueue_push(VALUE self, VALUE obj)
 {
     struct waiting_delete args;
-    args.waiting = GET_QUEUE_WAITERS(self);
+    args.waiting = GET_SZQUEUE_WAITERS(self);
     args.th      = rb_thread_current();
 
     while (queue_length(self) >= GET_SZQUEUE_ULONGMAX(self)) {

test/thread/test_queue.rb

@@ -134,6 +134,29 @@ def test_sized_queue_clear_return_value
     assert_same q, retval
   end
 
+  def test_sized_queue_throttle
+    q = SizedQueue.new(1)
+    i = 0
+    consumer = Thread.new do
+      while q.pop
+        i += 1
+        Thread.pass
+      end
+    end
+    nprod = 4
+    npush = 100
+
+    producer = nprod.times.map do
+      Thread.new do
+        npush.times { q.push(true) }
+      end
+    end
+    producer.each(&:join)
+    q.push(nil)
+    consumer.join
+    assert_equal(nprod * npush, i)
+  end
+
   def test_queue_thread_raise
     q = Queue.new
     th1 = Thread.new do