1 /*
2 * Copyright (C) 2008 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_MONITOR_INL_H_
18 #define ART_RUNTIME_MONITOR_INL_H_
19
20 #include "monitor.h"
21
22 #include "gc_root-inl.h"
23 #include "obj_ptr-inl.h"
24
25 namespace art {
26
27 template<ReadBarrierOption kReadBarrierOption>
GetObject()28 inline ObjPtr<mirror::Object> Monitor::GetObject() REQUIRES_SHARED(Locks::mutator_lock_) {
29 return obj_.Read<kReadBarrierOption>();
30 }
31
32 // Check for request to set lock owner info.
CheckLockOwnerRequest(Thread * self)33 void Monitor::CheckLockOwnerRequest(Thread* self) {
34 DCHECK(self != nullptr);
35 Thread* request_thread = lock_owner_request_.load(std::memory_order_relaxed);
36 if (request_thread == self) {
37 SetLockingMethod(self);
38 // Only do this the first time after a request.
39 lock_owner_request_.store(nullptr, std::memory_order_relaxed);
40 }
41 }
42
LockOwnerInfoChecksum(ArtMethod * m,uint32_t dex_pc,Thread * t)43 uintptr_t Monitor::LockOwnerInfoChecksum(ArtMethod* m, uint32_t dex_pc, Thread* t) {
44 uintptr_t dpc_and_thread = static_cast<uintptr_t>(dex_pc << 8) ^ reinterpret_cast<uintptr_t>(t);
45 return reinterpret_cast<uintptr_t>(m) ^ dpc_and_thread
46 ^ (dpc_and_thread << (/* ptr_size / 2 */ (sizeof m) << 2));
47 }
48
SetLockOwnerInfo(ArtMethod * method,uint32_t dex_pc,Thread * t)49 void Monitor::SetLockOwnerInfo(ArtMethod* method, uint32_t dex_pc, Thread* t) {
50 lock_owner_method_.store(method, std::memory_order_relaxed);
51 lock_owner_dex_pc_.store(dex_pc, std::memory_order_relaxed);
52 lock_owner_.store(t, std::memory_order_relaxed);
53 uintptr_t sum = LockOwnerInfoChecksum(method, dex_pc, t);
54 lock_owner_sum_.store(sum, std::memory_order_relaxed);
55 }
56
GetLockOwnerInfo(ArtMethod ** method,uint32_t * dex_pc,Thread * t)57 void Monitor::GetLockOwnerInfo(/*out*/ArtMethod** method, /*out*/uint32_t* dex_pc,
58 Thread* t) {
59 ArtMethod* owners_method;
60 uint32_t owners_dex_pc;
61 Thread* owner;
62 uintptr_t owners_sum;
63 DCHECK(t != nullptr);
64 do {
65 owner = lock_owner_.load(std::memory_order_relaxed);
66 if (owner == nullptr) {
67 break;
68 }
69 owners_method = lock_owner_method_.load(std::memory_order_relaxed);
70 owners_dex_pc = lock_owner_dex_pc_.load(std::memory_order_relaxed);
71 owners_sum = lock_owner_sum_.load(std::memory_order_relaxed);
72 } while (owners_sum != LockOwnerInfoChecksum(owners_method, owners_dex_pc, owner));
73 if (owner == t) {
74 *method = owners_method;
75 *dex_pc = owners_dex_pc;
76 } else {
77 *method = nullptr;
78 *dex_pc = 0;
79 }
80 }
81
82
83 } // namespace art
84
85 #endif // ART_RUNTIME_MONITOR_INL_H_
86