Add explicit monitor inflation run test.

This tests some of the same code as the monitor_pool_test
gtest. But it tests a larger pool size with the code needed to
invoke it from the Java level.  Larger pool sizes have gotten
more interesting with the new monitor pool layout.

Add a function to return the size of the current MonitorList.
Currently this is only used by this test, but it is likely to
have debugging or performance analysis uses as well.

Test: Passed on host and on angler.

Change-Id: I4f3f150044a0d8c800eb60635e074119598cfdd1

7 files changed, 133 insertions, 0 deletions

diff --git a/runtime/monitor.cc b/runtime/monitor.cc
index 9c0927584e..071b0e2c75 100644
--- a/runtime/monitor.cc
+++ b/runtime/monitor.cc
@@ -1394,6 +1394,12 @@ void MonitorList::SweepMonitorList(IsMarkedVisitor* visitor) {
   }
 }
 
+size_t MonitorList::Size() {
+  Thread* self = Thread::Current();
+  MutexLock mu(self, monitor_list_lock_);
+  return list_.size();
+}
+
 class MonitorDeflateVisitor : public IsMarkedVisitor {
  public:
   MonitorDeflateVisitor() : self_(Thread::Current()), deflate_count_(0) {}
diff --git a/runtime/monitor.h b/runtime/monitor.h
index c3da5636ad..1fa46826eb 100644
--- a/runtime/monitor.h
+++ b/runtime/monitor.h
@@ -331,6 +331,7 @@ class MonitorList {
   void BroadcastForNewMonitors() REQUIRES(!monitor_list_lock_);
   // Returns how many monitors were deflated.
   size_t DeflateMonitors() REQUIRES(!monitor_list_lock_) REQUIRES(Locks::mutator_lock_);
+  size_t Size() REQUIRES(!monitor_list_lock_);
 
   typedef std::list<Monitor*, TrackingAllocator<Monitor*, kAllocatorTagMonitorList>> Monitors;
 
diff --git a/test/596-monitor-inflation/expected.txt b/test/596-monitor-inflation/expected.txt
new file mode 100644
index 0000000000..2add6966a0
--- /dev/null
+++ b/test/596-monitor-inflation/expected.txt
@@ -0,0 +1,6 @@
+JNI_OnLoad called
+Monitor list grew by at least 4000 monitors
+Monitor list shrank correctly
+Finished first check
+Finished second check
+Total checks: 10000
diff --git a/test/596-monitor-inflation/info.txt b/test/596-monitor-inflation/info.txt
new file mode 100644
index 0000000000..81dedb60aa
--- /dev/null
+++ b/test/596-monitor-inflation/info.txt
@@ -0,0 +1,5 @@
+A simple test that forces many monitors to be inflated, while checking
+that hashcodes are consistently maintained.
+
+This allocates more monitors and hence may exercise the monitor pool
+differently, and with more context, than the monitor_pool_test gtest.
diff --git a/test/596-monitor-inflation/monitor_inflation.cc b/test/596-monitor-inflation/monitor_inflation.cc
new file mode 100644
index 0000000000..fb4275b711
--- /dev/null
+++ b/test/596-monitor-inflation/monitor_inflation.cc
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "gc/heap.h"
+#include "jni.h"
+#include "monitor.h"
+#include "runtime.h"
+#include "thread-inl.h"
+
+namespace art {
+namespace {
+
+extern "C" JNIEXPORT void JNICALL Java_Main_trim(JNIEnv*, jclass) {
+  Runtime::Current()->GetHeap()->Trim(Thread::Current());
+}
+
+extern "C" JNIEXPORT jint JNICALL Java_Main_monitorListSize(JNIEnv*, jclass) {
+  return Runtime::Current()->GetMonitorList()->Size();
+}
+
+}  // namespace
+}  // namespace art
diff --git a/test/596-monitor-inflation/src/Main.java b/test/596-monitor-inflation/src/Main.java
new file mode 100644
index 0000000000..d97c7667e9
--- /dev/null
+++ b/test/596-monitor-inflation/src/Main.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.util.IdentityHashMap;
+import dalvik.system.VMRuntime;
+
+public class Main {
+  public static void main(String[] args) {
+    System.loadLibrary(args[0]);
+    int initialSize = monitorListSize();
+    IdentityHashMap<Object, Integer> all = new IdentityHashMap();
+    for (int i = 0; i < 5000; ++i) {
+      Object obj = new Object();
+      synchronized(obj) {
+        // Should force inflation.
+        all.put(obj, obj.hashCode());
+      }
+    }
+    // Since monitor deflation is delayed significantly, we believe that even with an intervening
+    // GC, monitors should remain inflated.  We allow some slop for unrelated concurrent runtime
+    // actions.
+    int inflatedSize = monitorListSize();
+    if (inflatedSize >= initialSize + 4000) {
+        System.out.println("Monitor list grew by at least 4000 monitors");
+    } else {
+        System.out.println("Monitor list did not grow as expected");
+    }
+    // Encourage monitor deflation.
+    // trim() (Heap::Trim()) deflates only in JANK_IMPERCEPTIBLE state.
+    // Some of this mirrors code in ActivityThread.java.
+    final int DALVIK_PROCESS_STATE_JANK_PERCEPTIBLE = 0;
+    final int DALVIK_PROCESS_STATE_JANK_IMPERCEPTIBLE = 1;
+    VMRuntime.getRuntime().updateProcessState(DALVIK_PROCESS_STATE_JANK_IMPERCEPTIBLE);
+    System.gc();
+    System.runFinalization();
+    trim();
+    VMRuntime.getRuntime().updateProcessState(DALVIK_PROCESS_STATE_JANK_PERCEPTIBLE);
+    int finalSize = monitorListSize();
+    if (finalSize > initialSize + 1000) {
+        System.out.println("Monitor list failed to shrink properly");
+    } else {
+        System.out.println("Monitor list shrank correctly");
+    }
+    int j = 0;
+    for (Object obj: all.keySet()) {
+      ++j;
+      if (obj.hashCode() != all.get(obj)) {
+        throw new AssertionError("Failed hashcode test!");
+      }
+    }
+    System.out.println("Finished first check");
+    for (Object obj: all.keySet()) {
+      ++j;
+      synchronized(obj) {
+        if (obj.hashCode() != all.get(obj)) {
+          throw new AssertionError("Failed hashcode test!");
+        }
+      }
+    }
+    System.out.println("Finished second check");
+    System.out.println("Total checks: " + j);
+  }
+
+  private static native void trim();
+
+  private static native int monitorListSize();
+}
diff --git a/test/Android.bp b/test/Android.bp
index 965d07aa43..e820d28fa1 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -325,6 +325,7 @@ cc_defaults {
         "570-checker-osr/osr.cc",
         "595-profile-saving/profile-saving.cc",
         "596-app-images/app_images.cc",
+        "596-monitor-inflation/monitor_inflation.cc",
         "597-deopt-new-string/deopt.cc",
         "626-const-class-linking/clear_dex_cache_types.cc",
     ],