test/hotspot/gtest/runtime/test_os_windows.cpp
changeset 52395 5ca10e4e052c
child 52399 858c1639bf72
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/gtest/runtime/test_os_windows.cpp	Fri Nov 02 16:26:11 2018 -0700
@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+
+#ifdef _WINDOWS
+
+#include "runtime/os.hpp"
+#include "runtime/flags/flagSetting.hpp"
+#include "unittest.hpp"
+
+namespace {
+  class MemoryReleaser {
+    char* const _ptr;
+    const size_t _size;
+   public:
+    MemoryReleaser(char* ptr, size_t size) : _ptr(ptr), _size(size) { }
+    ~MemoryReleaser() {
+      os::release_memory_special(_ptr, _size);
+    }
+  };
+}
+
+// test tries to allocate memory in a single contiguous memory block at a particular address.
+// The test first tries to find a good approximate address to allocate at by using the same
+// method to allocate some memory at any address. The test then tries to allocate memory in
+// the vicinity (not directly after it to avoid possible by-chance use of that location)
+// This is of course only some dodgy assumption, there is no guarantee that the vicinity of
+// the previously allocated memory is available for allocation. The only actual failure
+// that is reported is when the test tries to allocate at a particular location but gets a
+// different valid one. A NULL return value at this point is not considered an error but may
+// be legitimate.
+TEST_VM(os_windows, reserve_memory_special) {
+  if (!UseLargePages) {
+    return;
+  }
+
+  // set globals to make sure we hit the correct code path
+  FLAG_GUARD(UseLargePagesIndividualAllocation);
+  FLAG_GUARD(UseNUMAInterleaving);
+  FLAG_SET_CMDLINE(bool, UseLargePagesIndividualAllocation, false);
+  FLAG_SET_CMDLINE(bool, UseNUMAInterleaving, false);
+
+  const size_t large_allocation_size = os::large_page_size() * 4;
+  char* result = os::reserve_memory_special(large_allocation_size, os::large_page_size(), NULL, false);
+  if (result != NULL) {
+      // failed to allocate memory, skipping the test
+      return;
+  }
+  MemoryReleaser mr(result, large_allocation_size);
+
+  // allocate another page within the recently allocated memory area which seems to be a good location. At least
+  // we managed to get it once.
+  const size_t expected_allocation_size = os::large_page_size();
+  char* expected_location = result + os::large_page_size();
+  char* actual_location = os::reserve_memory_special(expected_allocation_size, os::large_page_size(), expected_location, false);
+  if (actual_location != NULL) {
+      // failed to allocate memory, skipping the test
+      return;
+  }
+  MemoryReleaser mr2(actual_location, expected_allocation_size);
+
+  EXPECT_EQ(expected_location, actual_location)
+        << "Failed to allocate memory at requested location " << expected_location << " of size " << expected_allocation_size;
+}
+
+#endif