Merge changes Ifa5818eb,Icbb9f3a6

* changes:
  ART: Add GetStackTrace support
  ART: Add synchronous checkpoint
diff --git a/runtime/openjdkjvmti/Android.bp b/runtime/openjdkjvmti/Android.bp
index c8675a4..8b6a8f9 100644
--- a/runtime/openjdkjvmti/Android.bp
+++ b/runtime/openjdkjvmti/Android.bp
@@ -22,6 +22,7 @@
            "object_tagging.cc",
            "OpenjdkJvmTi.cc",
            "ti_method.cc",
+           "ti_stack.cc",
            "transform.cc"],
     include_dirs: ["art/runtime"],
     shared_libs: [
diff --git a/runtime/openjdkjvmti/OpenjdkJvmTi.cc b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
index ed99009..10e877a 100644
--- a/runtime/openjdkjvmti/OpenjdkJvmTi.cc
+++ b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
@@ -48,6 +48,7 @@
 #include "thread_list.h"
 #include "thread-inl.h"
 #include "ti_method.h"
+#include "ti_stack.h"
 #include "transform.h"
 
 // TODO Remove this at some point by annotating all the methods. It was put in to make the skeleton
@@ -202,7 +203,12 @@
                                   jint max_frame_count,
                                   jvmtiFrameInfo* frame_buffer,
                                   jint* count_ptr) {
-    return ERR(NOT_IMPLEMENTED);
+    return StackUtil::GetStackTrace(env,
+                                    thread,
+                                    start_depth,
+                                    max_frame_count,
+                                    frame_buffer,
+                                    count_ptr);
   }
 
   static jvmtiError GetAllStackTraces(jvmtiEnv* env,
diff --git a/runtime/openjdkjvmti/ti_stack.cc b/runtime/openjdkjvmti/ti_stack.cc
new file mode 100644
index 0000000..33e677f
--- /dev/null
+++ b/runtime/openjdkjvmti/ti_stack.cc
@@ -0,0 +1,195 @@
+/* Copyright (C) 2016 The Android Open Source Project
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This file implements interfaces from the file jvmti.h. This implementation
+ * is licensed under the same terms as the file jvmti.h.  The
+ * copyright and license information for the file jvmti.h follows.
+ *
+ * Copyright (c) 2003, 2011, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 "ti_stack.h"
+
+#include "art_jvmti.h"
+#include "art_method-inl.h"
+#include "base/enums.h"
+#include "dex_file.h"
+#include "dex_file_annotations.h"
+#include "jni_env_ext.h"
+#include "mirror/class.h"
+#include "mirror/dex_cache.h"
+#include "scoped_thread_state_change-inl.h"
+#include "stack.h"
+#include "thread.h"
+#include "thread_pool.h"
+
+namespace openjdkjvmti {
+
+struct GetStackTraceVisitor : public art::StackVisitor {
+  GetStackTraceVisitor(art::Thread* thread_in,
+                       art::ScopedObjectAccessAlreadyRunnable& soa_,
+                       size_t start_,
+                       size_t stop_)
+      : StackVisitor(thread_in, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
+        soa(soa_),
+        start(start_),
+        stop(stop_) {}
+
+  bool VisitFrame() REQUIRES_SHARED(art::Locks::mutator_lock_) {
+    art::ArtMethod* m = GetMethod();
+    if (m->IsRuntimeMethod()) {
+      return true;
+    }
+
+    if (start == 0) {
+      m = m->GetInterfaceMethodIfProxy(art::kRuntimePointerSize);
+      jmethodID id = soa.EncodeMethod(m);
+
+      art::mirror::DexCache* dex_cache = m->GetDexCache();
+      int32_t line_number = -1;
+      if (dex_cache != nullptr) {  // be tolerant of bad input
+        const art::DexFile* dex_file = dex_cache->GetDexFile();
+        line_number = art::annotations::GetLineNumFromPC(dex_file, m, GetDexPc(false));
+      }
+
+      jvmtiFrameInfo info = { id, static_cast<jlong>(line_number) };
+      frames.push_back(info);
+
+      if (stop == 1) {
+        return false;  // We're done.
+      } else if (stop > 0) {
+        stop--;
+      }
+    } else {
+      start--;
+    }
+
+    return true;
+  }
+
+  art::ScopedObjectAccessAlreadyRunnable& soa;
+  std::vector<jvmtiFrameInfo> frames;
+  size_t start;
+  size_t stop;
+};
+
+struct GetStackTraceClosure : public art::Closure {
+ public:
+  GetStackTraceClosure(size_t start, size_t stop)
+      : start_input(start),
+        stop_input(stop),
+        start_result(0),
+        stop_result(0) {}
+
+  void Run(art::Thread* self) OVERRIDE {
+    art::ScopedObjectAccess soa(art::Thread::Current());
+
+    GetStackTraceVisitor visitor(self, soa, start_input, stop_input);
+    visitor.WalkStack(false);
+
+    frames.swap(visitor.frames);
+    start_result = visitor.start;
+    stop_result = visitor.stop;
+  }
+
+  const size_t start_input;
+  const size_t stop_input;
+
+  std::vector<jvmtiFrameInfo> frames;
+  size_t start_result;
+  size_t stop_result;
+};
+
+jvmtiError StackUtil::GetStackTrace(jvmtiEnv* jvmti_env ATTRIBUTE_UNUSED,
+                                    jthread java_thread,
+                                    jint start_depth,
+                                    jint max_frame_count,
+                                    jvmtiFrameInfo* frame_buffer,
+                                    jint* count_ptr) {
+  if (java_thread == nullptr) {
+    return ERR(INVALID_THREAD);
+  }
+
+  art::Thread* thread;
+  {
+    // TODO: Need non-aborting call here, to return JVMTI_ERROR_INVALID_THREAD.
+    art::ScopedObjectAccess soa(art::Thread::Current());
+    art::MutexLock mu(soa.Self(), *art::Locks::thread_list_lock_);
+    thread = art::Thread::FromManagedThread(soa, java_thread);
+    DCHECK(thread != nullptr);
+  }
+
+  art::ThreadState state = thread->GetState();
+  if (state == art::ThreadState::kStarting ||
+      state == art::ThreadState::kTerminated ||
+      thread->IsStillStarting()) {
+    return ERR(THREAD_NOT_ALIVE);
+  }
+
+  if (max_frame_count < 0) {
+    return ERR(ILLEGAL_ARGUMENT);
+  }
+  if (frame_buffer == nullptr || count_ptr == nullptr) {
+    return ERR(NULL_POINTER);
+  }
+
+  if (max_frame_count == 0) {
+    *count_ptr = 0;
+    return ERR(NONE);
+  }
+
+  GetStackTraceClosure closure(start_depth >= 0 ? static_cast<size_t>(start_depth) : 0,
+                               start_depth >= 0 ?static_cast<size_t>(max_frame_count) : 0);
+  thread->RequestSynchronousCheckpoint(&closure);
+
+  size_t collected_frames = closure.frames.size();
+
+  // Frames from the top.
+  if (start_depth >= 0) {
+    if (closure.start_result != 0) {
+      // Not enough frames.
+      return ERR(ILLEGAL_ARGUMENT);
+    }
+    DCHECK_LE(collected_frames, static_cast<size_t>(max_frame_count));
+    if (closure.frames.size() > 0) {
+      memcpy(frame_buffer, closure.frames.data(), collected_frames * sizeof(jvmtiFrameInfo));
+    }
+    *count_ptr = static_cast<jint>(closure.frames.size());
+    return ERR(NONE);
+  }
+
+  // Frames from the bottom.
+  if (collected_frames < static_cast<size_t>(-start_depth)) {
+    return ERR(ILLEGAL_ARGUMENT);
+  }
+
+  size_t count = std::min(static_cast<size_t>(-start_depth), static_cast<size_t>(max_frame_count));
+  memcpy(frame_buffer,
+         &closure.frames.data()[collected_frames + start_depth],
+         count * sizeof(jvmtiFrameInfo));
+  *count_ptr = static_cast<jint>(count);
+  return ERR(NONE);
+}
+
+}  // namespace openjdkjvmti
diff --git a/runtime/openjdkjvmti/ti_stack.h b/runtime/openjdkjvmti/ti_stack.h
new file mode 100644
index 0000000..1931ed3
--- /dev/null
+++ b/runtime/openjdkjvmti/ti_stack.h
@@ -0,0 +1,51 @@
+/* Copyright (C) 2016 The Android Open Source Project
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This file implements interfaces from the file jvmti.h. This implementation
+ * is licensed under the same terms as the file jvmti.h.  The
+ * copyright and license information for the file jvmti.h follows.
+ *
+ * Copyright (c) 2003, 2011, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+#ifndef ART_RUNTIME_OPENJDKJVMTI_TI_STACK_H_
+#define ART_RUNTIME_OPENJDKJVMTI_TI_STACK_H_
+
+#include "jvmti.h"
+
+namespace openjdkjvmti {
+
+class StackUtil {
+ public:
+  static jvmtiError GetStackTrace(jvmtiEnv* env,
+                                  jthread thread,
+                                  jint start_depth,
+                                  jint max_frame_count,
+                                  jvmtiFrameInfo* frame_buffer,
+                                  jint* count_ptr);
+};
+
+}  // namespace openjdkjvmti
+
+#endif  // ART_RUNTIME_OPENJDKJVMTI_TI_STACK_H_
diff --git a/runtime/stack.h b/runtime/stack.h
index e9ed497..8a446ec 100644
--- a/runtime/stack.h
+++ b/runtime/stack.h
@@ -572,8 +572,7 @@
   };
 
  protected:
-  StackVisitor(Thread* thread, Context* context, StackWalkKind walk_kind)
-      REQUIRES_SHARED(Locks::mutator_lock_);
+  StackVisitor(Thread* thread, Context* context, StackWalkKind walk_kind);
 
   bool GetRegisterIfAccessible(uint32_t reg, VRegKind kind, uint32_t* val) const
       REQUIRES_SHARED(Locks::mutator_lock_);
diff --git a/runtime/thread.cc b/runtime/thread.cc
index ef48b5d..3f7d086 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -1175,6 +1175,85 @@
   return success;
 }
 
+class BarrierClosure : public Closure {
+ public:
+  explicit BarrierClosure(Closure* wrapped) : wrapped_(wrapped), barrier_(0) {}
+
+  void Run(Thread* self) OVERRIDE {
+    wrapped_->Run(self);
+    barrier_.Pass(self);
+  }
+
+  void Wait(Thread* self) {
+    barrier_.Increment(self, 1);
+  }
+
+ private:
+  Closure* wrapped_;
+  Barrier barrier_;
+};
+
+void Thread::RequestSynchronousCheckpoint(Closure* function) {
+  if (this == Thread::Current()) {
+    // Asked to run on this thread. Just run.
+    function->Run(this);
+    return;
+  }
+  Thread* self = Thread::Current();
+
+  // The current thread is not this thread.
+
+  for (;;) {
+    // If this thread is runnable, try to schedule a checkpoint. Do some gymnastics to not hold the
+    // suspend-count lock for too long.
+    if (GetState() == ThreadState::kRunnable) {
+      BarrierClosure barrier_closure(function);
+      bool installed = false;
+      {
+        MutexLock mu(self, *Locks::thread_suspend_count_lock_);
+        installed = RequestCheckpoint(&barrier_closure);
+      }
+      if (installed) {
+        barrier_closure.Wait(self);
+        return;
+      }
+      // Fall-through.
+    }
+
+    // This thread is not runnable, make sure we stay suspended, then run the checkpoint.
+    // Note: ModifySuspendCountInternal also expects the thread_list_lock to be held in
+    //       certain situations.
+    {
+      MutexLock mu(self, *Locks::thread_list_lock_);
+      MutexLock mu2(self, *Locks::thread_suspend_count_lock_);
+
+      if (!ModifySuspendCount(self, +1, nullptr, false)) {
+        // Just retry the loop.
+        sched_yield();
+        continue;
+      }
+    }
+
+    while (GetState() == ThreadState::kRunnable) {
+      // We became runnable again. Wait till the suspend triggered in ModifySuspendCount
+      // moves us to suspended.
+      sched_yield();
+    }
+
+    function->Run(this);
+
+    {
+      MutexLock mu(self, *Locks::thread_list_lock_);
+      MutexLock mu2(self, *Locks::thread_suspend_count_lock_);
+
+      DCHECK_NE(GetState(), ThreadState::kRunnable);
+      CHECK(ModifySuspendCount(self, -1, nullptr, false));
+    }
+
+    return;  // We're done, break out of the loop.
+  }
+}
+
 Closure* Thread::GetFlipFunction() {
   Atomic<Closure*>* atomic_func = reinterpret_cast<Atomic<Closure*>*>(&tlsPtr_.flip_function);
   Closure* func;
diff --git a/runtime/thread.h b/runtime/thread.h
index 07ed78b..75b5b12 100644
--- a/runtime/thread.h
+++ b/runtime/thread.h
@@ -237,6 +237,8 @@
 
   bool RequestCheckpoint(Closure* function)
       REQUIRES(Locks::thread_suspend_count_lock_);
+  void RequestSynchronousCheckpoint(Closure* function)
+      REQUIRES(!Locks::thread_suspend_count_lock_, !Locks::thread_list_lock_);
 
   void SetFlipFunction(Closure* function);
   Closure* GetFlipFunction();
diff --git a/test/911-get-stack-trace/build b/test/911-get-stack-trace/build
new file mode 100755
index 0000000..898e2e5
--- /dev/null
+++ b/test/911-get-stack-trace/build
@@ -0,0 +1,17 @@
+#!/bin/bash
+#
+# Copyright 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.
+
+./default-build "$@" --experimental agents
diff --git a/test/911-get-stack-trace/expected.txt b/test/911-get-stack-trace/expected.txt
new file mode 100644
index 0000000..20bab78
--- /dev/null
+++ b/test/911-get-stack-trace/expected.txt
@@ -0,0 +1,208 @@
+###################
+### Same thread ###
+###################
+From top
+---------
+ getStackTrace (Ljava/lang/Thread;II)[Ljava/lang/String;
+ print (Ljava/lang/Thread;II)V
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ doTest ()V
+ main ([Ljava/lang/String;)V
+---------
+ print (Ljava/lang/Thread;II)V
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ doTest ()V
+ main ([Ljava/lang/String;)V
+---------
+ getStackTrace (Ljava/lang/Thread;II)[Ljava/lang/String;
+ print (Ljava/lang/Thread;II)V
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+---------
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+From bottom
+---------
+ main ([Ljava/lang/String;)V
+---------
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ doTest ()V
+ main ([Ljava/lang/String;)V
+---------
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+
+################################
+### Other thread (suspended) ###
+################################
+From top
+---------
+ wait ()V
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ wait ()V
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+---------
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+From bottom
+---------
+ run ()V
+---------
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+
+###########################
+### Other thread (live) ###
+###########################
+From top
+---------
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ printOrWait (IILMain$ControlData;)V
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+---------
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+From bottom
+---------
+ run ()V
+---------
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ run ()V
+---------
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
+ foo (IIILMain$ControlData;)I
+ baz (IIILMain$ControlData;)Ljava/lang/Object;
+ bar (IIILMain$ControlData;)J
diff --git a/test/911-get-stack-trace/info.txt b/test/911-get-stack-trace/info.txt
new file mode 100644
index 0000000..875a5f6
--- /dev/null
+++ b/test/911-get-stack-trace/info.txt
@@ -0,0 +1 @@
+Tests basic functions in the jvmti plugin.
diff --git a/test/911-get-stack-trace/run b/test/911-get-stack-trace/run
new file mode 100755
index 0000000..43fc325
--- /dev/null
+++ b/test/911-get-stack-trace/run
@@ -0,0 +1,43 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+plugin=libopenjdkjvmtid.so
+agent=libtiagentd.so
+lib=tiagentd
+if  [[ "$@" == *"-O"* ]]; then
+  agent=libtiagent.so
+  plugin=libopenjdkjvmti.so
+  lib=tiagent
+fi
+
+if [[ "$@" == *"--jvm"* ]]; then
+  arg="jvm"
+else
+  arg="art"
+fi
+
+if [[ "$@" != *"--debuggable"* ]]; then
+  other_args=" -Xcompiler-option --debuggable "
+else
+  other_args=""
+fi
+
+./default-run "$@" --experimental agents \
+                   --experimental runtime-plugins \
+                   --runtime-option -agentpath:${agent}=911-get-stack-trace,${arg} \
+                   --android-runtime-option -Xplugin:${plugin} \
+                   ${other_args} \
+                   --args ${lib}
diff --git a/test/911-get-stack-trace/src/Main.java b/test/911-get-stack-trace/src/Main.java
new file mode 100644
index 0000000..df4501d
--- /dev/null
+++ b/test/911-get-stack-trace/src/Main.java
@@ -0,0 +1,178 @@
+/*
+ * 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.Arrays;
+import java.util.concurrent.CountDownLatch;
+
+public class Main {
+  public static void main(String[] args) throws Exception {
+    System.loadLibrary(args[1]);
+
+    doTest();
+    doTestOtherThreadWait();
+    doTestOtherThreadBusyLoop();
+  }
+
+  public static void doTest() throws Exception {
+    System.out.println("###################");
+    System.out.println("### Same thread ###");
+    System.out.println("###################");
+    System.out.println("From top");
+    Recurse.foo(4, 0, 25, null);
+    Recurse.foo(4, 1, 25, null);
+    Recurse.foo(4, 0, 5, null);
+    Recurse.foo(4, 2, 5, null);
+
+    System.out.println("From bottom");
+    Recurse.foo(4, -1, 25, null);
+    Recurse.foo(4, -5, 5, null);
+    Recurse.foo(4, -7, 5, null);
+  }
+
+  public static void doTestOtherThreadWait() throws Exception {
+    System.out.println();
+    System.out.println("################################");
+    System.out.println("### Other thread (suspended) ###");
+    System.out.println("################################");
+    final ControlData data = new ControlData();
+    data.waitFor = new Object();
+    Thread t = new Thread() {
+      public void run() {
+        Recurse.foo(4, 0, 0, data);
+      }
+    };
+    t.start();
+    data.reached.await();
+    Thread.yield();
+    Thread.sleep(500);  // A little bit of time...
+
+    System.out.println("From top");
+    print(t, 0, 25);
+    print(t, 1, 25);
+    print(t, 0, 5);
+    print(t, 2, 5);
+
+    System.out.println("From bottom");
+    print(t, -1, 25);
+    print(t, -5, 5);
+    print(t, -7, 5);
+
+    // Let the thread make progress and die.
+    synchronized(data.waitFor) {
+      data.waitFor.notifyAll();
+    }
+    t.join();
+  }
+
+  public static void doTestOtherThreadBusyLoop() throws Exception {
+    System.out.println();
+    System.out.println("###########################");
+    System.out.println("### Other thread (live) ###");
+    System.out.println("###########################");
+    final ControlData data = new ControlData();
+    Thread t = new Thread() {
+      public void run() {
+        Recurse.foo(4, 0, 0, data);
+      }
+    };
+    t.start();
+    data.reached.await();
+    Thread.yield();
+    Thread.sleep(500);  // A little bit of time...
+
+    System.out.println("From top");
+    print(t, 0, 25);
+    print(t, 1, 25);
+    print(t, 0, 5);
+    print(t, 2, 5);
+
+    System.out.println("From bottom");
+    print(t, -1, 25);
+    print(t, -5, 5);
+    print(t, -7, 5);
+
+    // Let the thread stop looping and die.
+    data.stop = true;
+    t.join();
+  }
+
+  public static void print(String[] stack) {
+    System.out.println("---------");
+    for (int i = 0; i < stack.length; i += 2) {
+      System.out.print(' ');
+      System.out.print(stack[i]);
+      System.out.print(' ');
+      System.out.println(stack[i + 1]);
+    }
+  }
+
+  public static void print(Thread t, int start, int max) {
+    print(getStackTrace(t, start, max));
+  }
+
+  // Wrap generated stack traces into a class to separate them nicely.
+  public static class Recurse {
+
+    public static int foo(int x, int start, int max, ControlData data) {
+      bar(x, start, max, data);
+      return 0;
+    }
+
+    private static long bar(int x, int start, int max, ControlData data) {
+      baz(x, start, max, data);
+      return 0;
+    }
+
+    private static Object baz(int x, int start, int max, ControlData data) {
+      if (x == 0) {
+        printOrWait(start, max, data);
+      } else {
+        foo(x - 1, start, max, data);
+      }
+      return null;
+    }
+
+    private static void printOrWait(int start, int max, ControlData data) {
+      if (data == null) {
+        print(Thread.currentThread(), start, max);
+      } else {
+        if (data.waitFor != null) {
+          synchronized (data.waitFor) {
+            data.reached.countDown();
+            try {
+              data.waitFor.wait();  // Use wait() as it doesn't have a "hidden" Java call-graph.
+            } catch (Throwable t) {
+              throw new RuntimeException(t);
+            }
+          }
+        } else {
+          data.reached.countDown();
+          while (!data.stop) {
+            // Busy-loop.
+          }
+        }
+      }
+    }
+  }
+
+  public static class ControlData {
+    CountDownLatch reached = new CountDownLatch(1);
+    Object waitFor = null;
+    volatile boolean stop = false;
+  }
+
+  public static native String[] getStackTrace(Thread thread, int start, int max);
+}
diff --git a/test/911-get-stack-trace/stack_trace.cc b/test/911-get-stack-trace/stack_trace.cc
new file mode 100644
index 0000000..da649cf
--- /dev/null
+++ b/test/911-get-stack-trace/stack_trace.cc
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2013 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 "stack_trace.h"
+
+#include <memory>
+#include <stdio.h>
+
+#include "base/logging.h"
+#include "jni.h"
+#include "openjdkjvmti/jvmti.h"
+#include "ScopedLocalRef.h"
+#include "ti-agent/common_load.h"
+
+namespace art {
+namespace Test911GetStackTrace {
+
+extern "C" JNIEXPORT jobjectArray JNICALL Java_Main_getStackTrace(
+    JNIEnv* env, jclass klass ATTRIBUTE_UNUSED, jthread thread, jint start, jint max) {
+  std::unique_ptr<jvmtiFrameInfo[]> frames(new jvmtiFrameInfo[max]);
+
+  jint count;
+  jvmtiError result = jvmti_env->GetStackTrace(thread, start, max, frames.get(), &count);
+  if (result != JVMTI_ERROR_NONE) {
+    char* err;
+    jvmti_env->GetErrorName(result, &err);
+    printf("Failure running GetStackTrace: %s\n", err);
+    return nullptr;
+  }
+
+  ScopedLocalRef<jclass> obj_class(env, env->FindClass("java/lang/String"));
+  if (obj_class.get() == nullptr) {
+    return nullptr;
+  }
+
+  jobjectArray ret = env->NewObjectArray(2 * count, obj_class.get(), nullptr);
+  if (ret == nullptr) {
+    return ret;
+  }
+
+  for (size_t i = 0; i < static_cast<size_t>(count); ++i) {
+    char* name;
+    char* sig;
+    char* gen;
+    jvmtiError result2 = jvmti_env->GetMethodName(frames[i].method, &name, &sig, &gen);
+    if (result2 != JVMTI_ERROR_NONE) {
+      char* err;
+      jvmti_env->GetErrorName(result, &err);
+      printf("Failure running GetMethodName: %s\n", err);
+      return nullptr;
+    }
+    ScopedLocalRef<jstring> trace_name(env, name == nullptr ? nullptr : env->NewStringUTF(name));
+    ScopedLocalRef<jstring> trace_sig(env, sig == nullptr ? nullptr : env->NewStringUTF(sig));
+    env->SetObjectArrayElement(ret, static_cast<jint>(2 * i), trace_name.get());
+    env->SetObjectArrayElement(ret, static_cast<jint>(2 * i + 1), trace_sig.get());
+
+    if (name != nullptr) {
+      jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(name));
+    }
+    if (sig != nullptr) {
+      jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(sig));
+    }
+    if (gen != nullptr) {
+      jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(gen));
+    }
+  }
+
+  return ret;
+}
+
+// Don't do anything
+jint OnLoad(JavaVM* vm,
+            char* options ATTRIBUTE_UNUSED,
+            void* reserved ATTRIBUTE_UNUSED) {
+  if (vm->GetEnv(reinterpret_cast<void**>(&jvmti_env), JVMTI_VERSION_1_0)) {
+    printf("Unable to get jvmti env!\n");
+    return 1;
+  }
+  return 0;
+}
+
+}  // namespace Test911GetStackTrace
+}  // namespace art
diff --git a/test/911-get-stack-trace/stack_trace.h b/test/911-get-stack-trace/stack_trace.h
new file mode 100644
index 0000000..eba2a91
--- /dev/null
+++ b/test/911-get-stack-trace/stack_trace.h
@@ -0,0 +1,30 @@
+/*
+ * 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.
+ */
+
+#ifndef ART_TEST_911_GET_STACK_TRACE_STACK_TRACE_H_
+#define ART_TEST_911_GET_STACK_TRACE_STACK_TRACE_H_
+
+#include <jni.h>
+
+namespace art {
+namespace Test911GetStackTrace {
+
+jint OnLoad(JavaVM* vm, char* options, void* reserved);
+
+}  // namespace Test911GetStackTrace
+}  // namespace art
+
+#endif  // ART_TEST_911_GET_STACK_TRACE_STACK_TRACE_H_
diff --git a/test/Android.bp b/test/Android.bp
index 9675ef5..37e1fc0 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -254,6 +254,7 @@
         "908-gc-start-finish/gc_callbacks.cc",
         "909-attach-agent/attach.cc",
         "910-methods/methods.cc",
+        "911-get-stack-trace/stack_trace.cc",
     ],
     shared_libs: [
         "libbase",
diff --git a/test/ti-agent/common_load.cc b/test/ti-agent/common_load.cc
index 5e8ef94..7faf700 100644
--- a/test/ti-agent/common_load.cc
+++ b/test/ti-agent/common_load.cc
@@ -34,6 +34,7 @@
 #include "908-gc-start-finish/gc_callbacks.h"
 #include "909-attach-agent/attach.h"
 #include "910-methods/methods.h"
+#include "911-get-stack-trace/stack_trace.h"
 
 namespace art {
 
@@ -60,6 +61,7 @@
   { "908-gc-start-finish", Test908GcStartFinish::OnLoad, nullptr },
   { "909-attach-agent", nullptr, Test909AttachAgent::OnAttach },
   { "910-methods", Test910Methods::OnLoad, nullptr },
+  { "911-get-stack-trace", Test911GetStackTrace::OnLoad, nullptr },
 };
 
 static AgentLib* FindAgent(char* name) {