1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ART_RUNTIME_SCOPED_THREAD_STATE_CHANGE_INL_H_
18#define ART_RUNTIME_SCOPED_THREAD_STATE_CHANGE_INL_H_
19
20#include "scoped_thread_state_change.h"
21
22#include "base/casts.h"
23#include "jni_env_ext-inl.h"
24#include "obj_ptr-inl.h"
25#include "thread-inl.h"
26
27namespace art {
28
29inline ScopedThreadStateChange::ScopedThreadStateChange(Thread* self, ThreadState new_thread_state)
30    : self_(self), thread_state_(new_thread_state), expected_has_no_thread_(false) {
31  if (UNLIKELY(self_ == nullptr)) {
32    // Value chosen arbitrarily and won't be used in the destructor since thread_ == null.
33    old_thread_state_ = kTerminated;
34    Runtime* runtime = Runtime::Current();
35    CHECK(runtime == nullptr || !runtime->IsStarted() || runtime->IsShuttingDown(self_));
36  } else {
37    DCHECK_EQ(self, Thread::Current());
38    // Read state without locks, ok as state is effectively thread local and we're not interested
39    // in the suspend count (this will be handled in the runnable transitions).
40    old_thread_state_ = self->GetState();
41    if (old_thread_state_ != new_thread_state) {
42      if (new_thread_state == kRunnable) {
43        self_->TransitionFromSuspendedToRunnable();
44      } else if (old_thread_state_ == kRunnable) {
45        self_->TransitionFromRunnableToSuspended(new_thread_state);
46      } else {
47        // A suspended transition to another effectively suspended transition, ok to use Unsafe.
48        self_->SetState(new_thread_state);
49      }
50    }
51  }
52}
53
54inline ScopedThreadStateChange::~ScopedThreadStateChange() {
55  if (UNLIKELY(self_ == nullptr)) {
56    if (!expected_has_no_thread_) {
57      Runtime* runtime = Runtime::Current();
58      bool shutting_down = (runtime == nullptr) || runtime->IsShuttingDown(nullptr);
59      CHECK(shutting_down);
60    }
61  } else {
62    if (old_thread_state_ != thread_state_) {
63      if (old_thread_state_ == kRunnable) {
64        self_->TransitionFromSuspendedToRunnable();
65      } else if (thread_state_ == kRunnable) {
66        self_->TransitionFromRunnableToSuspended(old_thread_state_);
67      } else {
68        // A suspended transition to another effectively suspended transition, ok to use Unsafe.
69        self_->SetState(old_thread_state_);
70      }
71    }
72  }
73}
74
75template<typename T>
76inline T ScopedObjectAccessAlreadyRunnable::AddLocalReference(ObjPtr<mirror::Object> obj) const {
77  Locks::mutator_lock_->AssertSharedHeld(Self());
78  if (kIsDebugBuild) {
79    CHECK(IsRunnable());  // Don't work with raw objects in non-runnable states.
80    DCheckObjIsNotClearedJniWeakGlobal(obj);
81  }
82  return obj == nullptr ? nullptr : Env()->AddLocalReference<T>(obj);
83}
84
85template<typename T>
86inline ObjPtr<T> ScopedObjectAccessAlreadyRunnable::Decode(jobject obj) const {
87  Locks::mutator_lock_->AssertSharedHeld(Self());
88  DCHECK(IsRunnable());  // Don't work with raw objects in non-runnable states.
89  return ObjPtr<T>::DownCast(Self()->DecodeJObject(obj));
90}
91
92inline bool ScopedObjectAccessAlreadyRunnable::IsRunnable() const {
93  return self_->GetState() == kRunnable;
94}
95
96inline ScopedObjectAccessAlreadyRunnable::ScopedObjectAccessAlreadyRunnable(JNIEnv* env)
97    : self_(ThreadForEnv(env)), env_(down_cast<JNIEnvExt*>(env)), vm_(env_->vm) {}
98
99inline ScopedObjectAccessAlreadyRunnable::ScopedObjectAccessAlreadyRunnable(Thread* self)
100    : self_(self),
101      env_(down_cast<JNIEnvExt*>(self->GetJniEnv())),
102      vm_(env_ != nullptr ? env_->vm : nullptr) {}
103
104inline ScopedObjectAccessUnchecked::ScopedObjectAccessUnchecked(JNIEnv* env)
105    : ScopedObjectAccessAlreadyRunnable(env), tsc_(Self(), kRunnable) {
106  Self()->VerifyStack();
107  Locks::mutator_lock_->AssertSharedHeld(Self());
108}
109
110inline ScopedObjectAccessUnchecked::ScopedObjectAccessUnchecked(Thread* self)
111    : ScopedObjectAccessAlreadyRunnable(self), tsc_(self, kRunnable) {
112  Self()->VerifyStack();
113  Locks::mutator_lock_->AssertSharedHeld(Self());
114}
115
116inline ScopedObjectAccess::ScopedObjectAccess(JNIEnv* env) : ScopedObjectAccessUnchecked(env) {}
117inline ScopedObjectAccess::ScopedObjectAccess(Thread* self) : ScopedObjectAccessUnchecked(self) {}
118inline ScopedObjectAccess::~ScopedObjectAccess() {}
119
120inline ScopedThreadSuspension::ScopedThreadSuspension(Thread* self, ThreadState suspended_state)
121    : self_(self), suspended_state_(suspended_state) {
122  DCHECK(self_ != nullptr);
123  self_->TransitionFromRunnableToSuspended(suspended_state);
124}
125
126inline ScopedThreadSuspension::~ScopedThreadSuspension() {
127  DCHECK_EQ(self_->GetState(), suspended_state_);
128  self_->TransitionFromSuspendedToRunnable();
129}
130
131}  // namespace art
132
133#endif  // ART_RUNTIME_SCOPED_THREAD_STATE_CHANGE_INL_H_
134