# HG changeset patch
# User stefank
# Date 1404979606 -7200
#      Thu Jul 10 10:06:46 2014 +0200
# Node ID 3fbad72da41755b3948dcac0f8527899bcfed8d1
# Parent  7fdf4173cde4025503ebe97abb36461886e3c2c4
8049831: Metadata Full GCs are not triggered when CMSClassUnloadingEnabled is turned off

diff --git a/src/share/vm/gc_implementation/shared/vmGCOperations.cpp b/src/share/vm/gc_implementation/shared/vmGCOperations.cpp
--- a/src/share/vm/gc_implementation/shared/vmGCOperations.cpp
+++ b/src/share/vm/gc_implementation/shared/vmGCOperations.cpp
@@ -197,28 +197,29 @@
 
 bool VM_CollectForMetadataAllocation::initiate_concurrent_GC() {
 #if INCLUDE_ALL_GCS
-  if (UseConcMarkSweepGC || UseG1GC) {
-    if (UseConcMarkSweepGC && CMSClassUnloadingEnabled) {
-      MetaspaceGC::set_should_concurrent_collect(true);
-    } else if (UseG1GC) {
-      G1CollectedHeap* g1h = G1CollectedHeap::heap();
-      g1h->g1_policy()->set_initiate_conc_mark_if_possible();
+  if (UseConcMarkSweepGC && CMSClassUnloadingEnabled) {
+    MetaspaceGC::set_should_concurrent_collect(true);
+    return true;
+  }
 
-      GCCauseSetter x(g1h, _gc_cause);
+  if (UseG1GC) {
+    G1CollectedHeap* g1h = G1CollectedHeap::heap();
+    g1h->g1_policy()->set_initiate_conc_mark_if_possible();
 
-      // At this point we are supposed to start a concurrent cycle. We
-      // will do so if one is not already in progress.
-      bool should_start = g1h->g1_policy()->force_initial_mark_if_outside_cycle(_gc_cause);
+    GCCauseSetter x(g1h, _gc_cause);
 
-      if (should_start) {
-        double pause_target = g1h->g1_policy()->max_pause_time_ms();
-        g1h->do_collection_pause_at_safepoint(pause_target);
-      }
+    // At this point we are supposed to start a concurrent cycle. We
+    // will do so if one is not already in progress.
+    bool should_start = g1h->g1_policy()->force_initial_mark_if_outside_cycle(_gc_cause);
+
+    if (should_start) {
+      double pause_target = g1h->g1_policy()->max_pause_time_ms();
+      g1h->do_collection_pause_at_safepoint(pause_target);
     }
-
     return true;
   }
 #endif
+
   return false;
 }
 
diff --git a/test/gc/class_unloading/TestCMSClassUnloadingDisabledHWM.java b/test/gc/class_unloading/TestCMSClassUnloadingDisabledHWM.java
new file mode 100644
--- /dev/null
+++ b/test/gc/class_unloading/TestCMSClassUnloadingDisabledHWM.java
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2014, 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.
+ */
+
+/*
+ * @test
+ * @key gc
+ * @bug 8049831
+ * @library /testlibrary /testlibrary/whitebox
+ * @build TestCMSClassUnloadingDisabledHWM
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main TestCMSClassUnloadingDisabledHWM
+ * @summary Test that -XX:-CMSClassUnloadingEnabled will trigger a Full GC when more than MetaspaceSize metadata is allocated.
+ */
+
+import com.oracle.java.testlibrary.*;
+import sun.hotspot.WhiteBox;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+public class TestCMSClassUnloadingDisabledHWM {
+
+  private static OutputAnalyzer run(long metaspaceSize, long youngGenSize) throws Exception {
+      ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
+        "-Xbootclasspath/a:.",
+        "-XX:+WhiteBoxAPI",
+        "-XX:MetaspaceSize=" + metaspaceSize,
+        "-Xmn" + youngGenSize,
+        "-XX:+UseConcMarkSweepGC",
+        "-XX:-CMSClassUnloadingEnabled",
+        "-XX:+PrintHeapAtGC",
+        "-XX:+PrintGCDetails",
+        "AllocateBeyondMetaspaceSize",
+        "" + metaspaceSize,
+        "" + youngGenSize);
+    return new OutputAnalyzer(pb.start());
+  }
+
+  public static void main(String args[]) throws Exception {
+    long metaspaceSize = 32 * 1024 * 1024;
+    long youngGenSize = 32 * 1024 * 1024;
+
+    OutputAnalyzer out = run(metaspaceSize, youngGenSize);
+
+    // -XX:-CMSClassUnloadingEnabled is used, so we expect a full GC instead of a concurrent cycle.
+    out.shouldMatch(".*Full GC.*");
+    out.shouldNotMatch(".*CMS Initial Mark.*");
+  }
+}
+
+class AllocateBeyondMetaspaceSize {
+  public static Object dummy;
+
+  public static void main(String [] args) {
+    if (args.length != 2) {
+      throw new IllegalArgumentException("Usage: <MetaspaceSize> <YoungGenSize>");
+    }
+
+    long metaspaceSize = Long.parseLong(args[0]);
+    long youngGenSize = Long.parseLong(args[1]);
+
+    run(metaspaceSize, youngGenSize);
+  }
+
+  private static void run(long metaspaceSize, long youngGenSize) {
+    WhiteBox wb = WhiteBox.getWhiteBox();
+
+    long allocationBeyondMetaspaceSize  = metaspaceSize * 2;
+    long metaspace = wb.allocateMetaspace(null, allocationBeyondMetaspaceSize);
+
+    triggerYoungGC(youngGenSize);
+
+    wb.freeMetaspace(null, metaspace, metaspace);
+  }
+
+  private static void triggerYoungGC(long youngGenSize) {
+    long approxAllocSize = 32 * 1024;
+    long numAllocations  = 2 * youngGenSize / approxAllocSize;
+
+    for (long i = 0; i < numAllocations; i++) {
+      dummy = new byte[(int)approxAllocSize];
+    }
+  }
+}