/* Copyright (C) 2017 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
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*/
#include "ti_threadgroup.h"
#include "art_field-inl.h"
#include "art_jvmti.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/mutex.h"
#include "handle_scope-inl.h"
#include "jni/jni_internal.h"
#include "mirror/class.h"
#include "mirror/object-inl.h"
#include "mirror/string.h"
#include "obj_ptr.h"
#include "object_lock.h"
#include "runtime.h"
#include "scoped_thread_state_change-inl.h"
#include "thread-current-inl.h"
#include "thread_list.h"
#include "well_known_classes.h"
namespace openjdkjvmti {
jvmtiError ThreadGroupUtil::GetTopThreadGroups(jvmtiEnv* env,
jint* group_count_ptr,
jthreadGroup** groups_ptr) {
// We only have a single top group. So we can take the current thread and move upwards.
if (group_count_ptr == nullptr || groups_ptr == nullptr) {
return ERR(NULL_POINTER);
}
art::Runtime* runtime = art::Runtime::Current();
if (runtime == nullptr) {
// Must be starting the runtime, or dying.
return ERR(WRONG_PHASE);
}
jobject sys_thread_group = runtime->GetSystemThreadGroup();
if (sys_thread_group == nullptr) {
// Seems we're still starting up.
return ERR(WRONG_PHASE);
}
unsigned char* data;
jvmtiError result = env->Allocate(sizeof(jthreadGroup), &data);
if (result != ERR(NONE)) {
return result;
}
jthreadGroup* groups = reinterpret_cast<jthreadGroup*>(data);
*groups =
reinterpret_cast<JNIEnv*>(art::Thread::Current()->GetJniEnv())->NewLocalRef(sys_thread_group);
*groups_ptr = groups;
*group_count_ptr = 1;
return ERR(NONE);
}
jvmtiError ThreadGroupUtil::GetThreadGroupInfo(jvmtiEnv* env,
jthreadGroup group,
jvmtiThreadGroupInfo* info_ptr) {
if (group == nullptr) {
return ERR(INVALID_THREAD_GROUP);
}
art::ScopedObjectAccess soa(art::Thread::Current());
if (soa.Env()->IsInstanceOf(group, art::WellKnownClasses::java_lang_ThreadGroup) == JNI_FALSE) {
return ERR(INVALID_THREAD_GROUP);
}
art::ObjPtr<art::mirror::Object> obj = soa.Decode<art::mirror::Object>(group);
// Do the name first. It's the only thing that can fail.
{
art::ArtField* name_field =
art::jni::DecodeArtField(art::WellKnownClasses::java_lang_ThreadGroup_name);
CHECK(name_field != nullptr);
art::ObjPtr<art::mirror::String> name_obj =
art::ObjPtr<art::mirror::String>::DownCast(name_field->GetObject(obj));
std::string tmp_str;
const char* tmp_cstr;
if (name_obj == nullptr) {
tmp_cstr = "";
} else {
tmp_str = name_obj->ToModifiedUtf8();
tmp_cstr = tmp_str.c_str();
}
jvmtiError result;
JvmtiUniquePtr<char[]> copy = CopyString(env, tmp_cstr, &result);
if (copy == nullptr) {
return result;
}
info_ptr->name = copy.release();
}
// Parent.
{
art::ArtField* parent_field =
art::jni::DecodeArtField(art::WellKnownClasses::java_lang_ThreadGroup_parent);
CHECK(parent_field != nullptr);
art::ObjPtr<art::mirror::Object> parent_group = parent_field->GetObject(obj);
info_ptr->parent = parent_group == nullptr
? nullptr
: soa.AddLocalReference<jthreadGroup>(parent_group);
}
// Max priority.
{
art::ArtField* prio_field = obj->GetClass()->FindDeclaredInstanceField("maxPriority", "I");
CHECK(prio_field != nullptr);
info_ptr->max_priority = static_cast<jint>(prio_field->GetInt(obj));
}
// Daemon.
{
art::ArtField* daemon_field = obj->GetClass()->FindDeclaredInstanceField("daemon", "Z");
CHECK(daemon_field != nullptr);
info_ptr->is_daemon = daemon_field->GetBoolean(obj) == 0 ? JNI_FALSE : JNI_TRUE;
}
return ERR(NONE);
}
static bool IsInDesiredThreadGroup(art::Handle<art::mirror::Object> desired_thread_group,
art::ObjPtr<art::mirror::Object> peer)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
CHECK(desired_thread_group != nullptr);
art::ArtField* thread_group_field =
art::jni::DecodeArtField(art::WellKnownClasses::java_lang_Thread_group);
DCHECK(thread_group_field != nullptr);
art::ObjPtr<art::mirror::Object> group = thread_group_field->GetObject(peer);
return (group == desired_thread_group.Get());
}
static void GetThreads(art::Handle<art::mirror::Object> thread_group,
std::vector<art::ObjPtr<art::mirror::Object>>* thread_peers)
REQUIRES_SHARED(art::Locks::mutator_lock_) REQUIRES(!art::Locks::thread_list_lock_) {
CHECK(thread_group != nullptr);
art::MutexLock mu(art::Thread::Current(), *art::Locks::thread_list_lock_);
for (art::Thread* t : art::Runtime::Current()->GetThreadList()->GetList()) {
if (t->IsStillStarting()) {
continue;
}
art::ObjPtr<art::mirror::Object> peer = t->GetPeerFromOtherThread();
if (peer == nullptr) {
continue;
}
if (IsInDesiredThreadGroup(thread_group, peer)) {
thread_peers->push_back(peer);
}
}
}
static void GetChildThreadGroups(art::Handle<art::mirror::Object> thread_group,
std::vector<art::ObjPtr<art::mirror::Object>>* thread_groups)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
CHECK(thread_group != nullptr);
// Get the ThreadGroup[] "groups" out of this thread group...
art::ArtField* groups_field =
art::jni::DecodeArtField(art::WellKnownClasses::java_lang_ThreadGroup_groups);
art::ObjPtr<art::mirror::Object> groups_array = groups_field->GetObject(thread_group.Get());
if (groups_array == nullptr) {
return;
}
CHECK(groups_array->IsObjectArray());
art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> groups_array_as_array =
groups_array->AsObjectArray<art::mirror::Object>();
// Copy all non-null elements.
for (int32_t i = 0; i < groups_array_as_array->GetLength(); ++i) {
art::ObjPtr<art::mirror::Object> entry = groups_array_as_array->Get(i);
if (entry != nullptr) {
thread_groups->push_back(entry);
}
}
}
jvmtiError ThreadGroupUtil::GetThreadGroupChildren(jvmtiEnv* env,
jthreadGroup group,
jint* thread_count_ptr,
jthread** threads_ptr,
jint* group_count_ptr,
jthreadGroup** groups_ptr) {
if (group == nullptr) {
return ERR(INVALID_THREAD_GROUP);
}
art::ScopedObjectAccess soa(art::Thread::Current());
if (!soa.Env()->IsInstanceOf(group, art::WellKnownClasses::java_lang_ThreadGroup)) {
return ERR(INVALID_THREAD_GROUP);
}
art::StackHandleScope<1> hs(soa.Self());
art::Handle<art::mirror::Object> thread_group = hs.NewHandle(
soa.Decode<art::mirror::Object>(group));
art::ObjectLock<art::mirror::Object> thread_group_lock(soa.Self(), thread_group);
std::vector<art::ObjPtr<art::mirror::Object>> thread_peers;
GetThreads(thread_group, &thread_peers);
std::vector<art::ObjPtr<art::mirror::Object>> thread_groups;
GetChildThreadGroups(thread_group, &thread_groups);
JvmtiUniquePtr<jthread[]> peers_uptr;
if (!thread_peers.empty()) {
jvmtiError res;
peers_uptr = AllocJvmtiUniquePtr<jthread[]>(env, thread_peers.size(), &res);
if (peers_uptr == nullptr) {
return res;
}
}
JvmtiUniquePtr<jthreadGroup[]> group_uptr;
if (!thread_groups.empty()) {
jvmtiError res;
group_uptr = AllocJvmtiUniquePtr<jthreadGroup[]>(env, thread_groups.size(), &res);
if (group_uptr == nullptr) {
return res;
}
}
// Can't fail anymore from here on.
// Copy data into out buffers.
for (size_t i = 0; i != thread_peers.size(); ++i) {
peers_uptr[i] = soa.AddLocalReference<jthread>(thread_peers[i]);
}
for (size_t i = 0; i != thread_groups.size(); ++i) {
group_uptr[i] = soa.AddLocalReference<jthreadGroup>(thread_groups[i]);
}
*thread_count_ptr = static_cast<jint>(thread_peers.size());
*threads_ptr = peers_uptr.release();
*group_count_ptr = static_cast<jint>(thread_groups.size());
*groups_ptr = group_uptr.release();
return ERR(NONE);
}
} // namespace openjdkjvmti