# HG changeset patch
# User jwilhelm
# Date 1508623829 -7200
# Node ID 50aa24ce898c27d4ca276c54a7982af475176273
# Parent  4dd1715f647fa9225126e8747750e8e90b157178# Parent  80267ddfdcfaf52e14655ce1bff0cc95e91987b7
Merge

diff -r 4dd1715f647f -r 50aa24ce898c src/hotspot/share/runtime/perfMemory.cpp
--- a/src/hotspot/share/runtime/perfMemory.cpp	Sat Oct 21 01:23:52 2017 +0200
+++ b/src/hotspot/share/runtime/perfMemory.cpp	Sun Oct 22 00:10:29 2017 +0200
@@ -53,6 +53,7 @@
 size_t                   PerfMemory::_capacity = 0;
 jint                     PerfMemory::_initialized = false;
 PerfDataPrologue*        PerfMemory::_prologue = NULL;
+bool                     PerfMemory::_destroyed = false;
 
 void perfMemory_init() {
 
@@ -64,7 +65,7 @@
 void perfMemory_exit() {
 
   if (!UsePerfData) return;
-  if (!PerfMemory::is_initialized()) return;
+  if (!PerfMemory::is_usable()) return;
 
   // Only destroy PerfData objects if we're at a safepoint and the
   // StatSampler is not active. Otherwise, we risk removing PerfData
@@ -88,7 +89,7 @@
 
 void PerfMemory::initialize() {
 
-  if (_prologue != NULL)
+  if (is_initialized())
     // initialization already performed
     return;
 
@@ -160,7 +161,7 @@
 
 void PerfMemory::destroy() {
 
-  if (_prologue == NULL) return;
+  if (!is_usable()) return;
 
   if (_start != NULL && _prologue->overflow != 0) {
 
@@ -196,11 +197,7 @@
     delete_memory_region();
   }
 
-  _start = NULL;
-  _end = NULL;
-  _top = NULL;
-  _prologue = NULL;
-  _capacity = 0;
+  _destroyed = true;
 }
 
 // allocate an aligned block of memory from the PerfData memory
@@ -213,7 +210,7 @@
 
   MutexLocker ml(PerfDataMemAlloc_lock);
 
-  assert(_prologue != NULL, "called before initialization");
+  assert(is_usable(), "called before init or after destroy");
 
   // check that there is enough memory for this request
   if ((_top + size) >= _end) {
@@ -238,6 +235,8 @@
 void PerfMemory::mark_updated() {
   if (!UsePerfData) return;
 
+  assert(is_usable(), "called before init or after destroy");
+
   _prologue->mod_time_stamp = os::elapsed_counter();
 }
 
@@ -268,3 +267,7 @@
 
   return dest_file;
 }
+
+bool PerfMemory::is_initialized() {
+  return OrderAccess::load_acquire(&_initialized) != 0;
+}
diff -r 4dd1715f647f -r 50aa24ce898c src/hotspot/share/runtime/perfMemory.hpp
--- a/src/hotspot/share/runtime/perfMemory.hpp	Sat Oct 21 01:23:52 2017 +0200
+++ b/src/hotspot/share/runtime/perfMemory.hpp	Sun Oct 22 00:10:29 2017 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2017, 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
@@ -113,6 +113,7 @@
  */
 class PerfMemory : AllStatic {
     friend class VMStructs;
+    friend class PerfMemoryTest;
   private:
     static char*  _start;
     static char*  _end;
@@ -120,6 +121,7 @@
     static size_t _capacity;
     static PerfDataPrologue*  _prologue;
     static jint   _initialized;
+    static bool   _destroyed;
 
     static void create_memory_region(size_t sizep);
     static void delete_memory_region();
@@ -135,7 +137,9 @@
     static char* end() { return _end; }
     static size_t used() { return (size_t) (_top - _start); }
     static size_t capacity() { return _capacity; }
-    static bool is_initialized() { return _initialized != 0; }
+    static bool is_initialized();
+    static bool is_destroyed() { return _destroyed; }
+    static bool is_usable() { return is_initialized() && !is_destroyed(); }
     static bool contains(char* addr) {
       return ((_start != NULL) && (addr >= _start) && (addr < _end));
     }
diff -r 4dd1715f647f -r 50aa24ce898c test/hotspot/gtest/runtime/test_perfdata.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/gtest/runtime/test_perfdata.cpp	Sun Oct 22 00:10:29 2017 +0200
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2017, 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"
+#include "runtime/perfMemory.hpp"
+#include "unittest.hpp"
+
+class PerfMemoryTest : public ::testing::Test {
+  public:
+    static char* top() { return PerfMemory::_top; }
+    static PerfDataPrologue* prologue() { return PerfMemory::_prologue; }
+};
+
+TEST_VM_F(PerfMemoryTest, destroy) {
+  PerfMemory::destroy();
+
+  ASSERT_NE(PerfMemory::start(), (char*)NULL) << "PerfMemory::_start should not be NULL";
+  ASSERT_NE(PerfMemory::end(), (char*)NULL) << "PerfMemory::_end should not be NULL";
+  ASSERT_NE(PerfMemoryTest::top(), (char*)NULL) << "PerfMemory::_top should not be NULL";
+  ASSERT_NE(PerfMemoryTest::prologue(), (PerfDataPrologue*)NULL) << "PerfMemory::_prologue should not be NULL";
+  ASSERT_NE(PerfMemory::capacity(), (size_t)0) << "PerfMemory::_capacity should not be 0";
+}
+