1 /*
   2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc/shared/ptrQueue.hpp"
  27 #include "runtime/mutex.hpp"
  28 #include "unittest.hpp"
  29 
  30 // Some basic testing of BufferNode::Allocator.
  31 TEST_VM(PtrQueueBufferAllocatorTest, test) {
  32   Mutex m(Mutex::leaf, "PtrQueueBufferAllocatorTest",
  33           false, Mutex::_safepoint_check_never);
  34   BufferNode::Allocator allocator(256, &m);
  35 
  36   // Allocate some new nodes for use in testing.
  37   BufferNode* nodes[10] = {};
  38   const size_t node_count = ARRAY_SIZE(nodes);
  39   for (size_t i = 0; i < node_count; ++i) {
  40     ASSERT_EQ(0u, allocator.free_count());
  41     nodes[i] = allocator.allocate();
  42     ASSERT_EQ((BufferNode*)NULL, nodes[i]->next());
  43   }
  44 
  45   // Release the nodes, adding them to the allocator's free list.
  46   for (size_t i = 0; i < node_count; ++i) {
  47     ASSERT_EQ(i, allocator.free_count());
  48     allocator.release(nodes[i]);
  49     if (i == 0) {
  50       ASSERT_EQ((BufferNode*)NULL, nodes[i]->next());
  51     } else {
  52       ASSERT_EQ(nodes[i - 1], nodes[i]->next());
  53     }
  54   }
  55 
  56   // Allocate nodes from the free list.
  57   for (size_t i = 0; i < node_count; ++i) {
  58     size_t j = node_count - i;
  59     ASSERT_EQ(j, allocator.free_count());
  60     ASSERT_EQ(nodes[j - 1], allocator.allocate());
  61   }
  62   ASSERT_EQ(0u, allocator.free_count());
  63 
  64   // Release nodes back to the free list.
  65   for (size_t i = 0; i < node_count; ++i) {
  66     allocator.release(nodes[i]);
  67   }
  68   ASSERT_EQ(node_count, allocator.free_count());
  69 
  70   // Destroy some nodes in the free list.
  71   // We don't have a way to verify destruction, but we can at
  72   // leat verify we don't crash along the way.
  73   allocator.reduce_free_list();
  74   // destroy allocator.
  75 }