Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 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 | |
Brian Carlstrom | fc0e321 | 2013-07-17 14:40:12 -0700 | [diff] [blame] | 17 | #ifndef ART_RUNTIME_MONITOR_H_ |
| 18 | #define ART_RUNTIME_MONITOR_H_ |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 19 | |
| 20 | #include <pthread.h> |
| 21 | #include <stdint.h> |
Brian Carlstrom | c57ad20 | 2015-03-03 21:21:29 -0800 | [diff] [blame] | 22 | #include <stdlib.h> |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 23 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 24 | #include <atomic> |
Elliott Hughes | 8e4aac5 | 2011-09-26 17:03:36 -0700 | [diff] [blame] | 25 | #include <iosfwd> |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 26 | #include <list> |
Elliott Hughes | f327e07 | 2013-01-09 16:01:26 -0800 | [diff] [blame] | 27 | #include <vector> |
Elliott Hughes | 8e4aac5 | 2011-09-26 17:03:36 -0700 | [diff] [blame] | 28 | |
Mathieu Chartier | bad0267 | 2014-08-25 13:08:22 -0700 | [diff] [blame] | 29 | #include "base/allocator.h" |
David Sehr | c431b9d | 2018-03-02 12:01:51 -0800 | [diff] [blame] | 30 | #include "base/atomic.h" |
Elliott Hughes | 76b6167 | 2012-12-12 17:47:30 -0800 | [diff] [blame] | 31 | #include "base/mutex.h" |
Hiroshi Yamauchi | 94f7b49 | 2014-07-22 18:08:23 -0700 | [diff] [blame] | 32 | #include "gc_root.h" |
Hiroshi Yamauchi | e15ea08 | 2015-02-09 17:11:42 -0800 | [diff] [blame] | 33 | #include "lock_word.h" |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 34 | #include "obj_ptr.h" |
Hiroshi Yamauchi | 94f7b49 | 2014-07-22 18:08:23 -0700 | [diff] [blame] | 35 | #include "read_barrier_option.h" |
Alex Light | 77fee87 | 2017-09-05 14:51:49 -0700 | [diff] [blame] | 36 | #include "runtime_callbacks.h" |
Ian Rogers | 2dd0e2c | 2013-01-24 12:42:14 -0800 | [diff] [blame] | 37 | #include "thread_state.h" |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 38 | |
| 39 | namespace art { |
| 40 | |
Mathieu Chartier | e401d14 | 2015-04-22 13:56:20 -0700 | [diff] [blame] | 41 | class ArtMethod; |
Andreas Gampe | 5d08fcc | 2017-06-05 17:56:46 -0700 | [diff] [blame] | 42 | class IsMarkedVisitor; |
Ian Rogers | b0fa5dc | 2014-04-28 16:47:08 -0700 | [diff] [blame] | 43 | class LockWord; |
Mathieu Chartier | eb8167a | 2014-05-07 15:43:14 -0700 | [diff] [blame] | 44 | template<class T> class Handle; |
Ian Rogers | b0fa5dc | 2014-04-28 16:47:08 -0700 | [diff] [blame] | 45 | class StackVisitor; |
Mathieu Chartier | e401d14 | 2015-04-22 13:56:20 -0700 | [diff] [blame] | 46 | class Thread; |
Ian Rogers | b0fa5dc | 2014-04-28 16:47:08 -0700 | [diff] [blame] | 47 | typedef uint32_t MonitorId; |
Mathieu Chartier | c645f1d | 2014-03-06 18:11:53 -0800 | [diff] [blame] | 48 | |
Ian Rogers | 2dd0e2c | 2013-01-24 12:42:14 -0800 | [diff] [blame] | 49 | namespace mirror { |
Igor Murashkin | 2ffb703 | 2017-11-08 13:35:21 -0800 | [diff] [blame] | 50 | class Object; |
Ian Rogers | 2dd0e2c | 2013-01-24 12:42:14 -0800 | [diff] [blame] | 51 | } // namespace mirror |
Ian Rogers | ef7d42f | 2014-01-06 12:55:46 -0800 | [diff] [blame] | 52 | |
Alex Light | 77fee87 | 2017-09-05 14:51:49 -0700 | [diff] [blame] | 53 | enum class LockReason { |
| 54 | kForWait, |
| 55 | kForLock, |
| 56 | }; |
| 57 | |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 58 | class Monitor { |
| 59 | public: |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 60 | // The default number of spins that are done before thread suspension is used to forcibly inflate |
| 61 | // a lock word. See Runtime::max_spins_before_thin_lock_inflation_. |
| 62 | constexpr static size_t kDefaultMaxSpinsBeforeThinLockInflation = 50; |
| 63 | |
wangguibo | e1484e9 | 2021-04-24 11:27:06 +0800 | [diff] [blame^] | 64 | static constexpr int kDefaultMonitorTimeoutMs = 500; |
| 65 | |
| 66 | static constexpr int kMonitorTimeoutMinMs = 200; |
| 67 | |
| 68 | static constexpr int kMonitorTimeoutMaxMs = 1000; // 1 second |
| 69 | |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 70 | ~Monitor(); |
| 71 | |
Andreas Gampe | d0210e5 | 2017-06-23 13:38:09 -0700 | [diff] [blame] | 72 | static void Init(uint32_t lock_profiling_threshold, uint32_t stack_dump_lock_profiling_threshold); |
Elliott Hughes | 32d6e1e | 2011-10-11 14:47:44 -0700 | [diff] [blame] | 73 | |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 74 | // Return the thread id of the lock owner or 0 when there is no owner. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 75 | static uint32_t GetLockOwnerThreadId(ObjPtr<mirror::Object> obj) |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 76 | NO_THREAD_SAFETY_ANALYSIS; // TODO: Reading lock owner without holding lock is racy. |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 77 | |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 78 | // NO_THREAD_SAFETY_ANALYSIS for mon->Lock. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 79 | static ObjPtr<mirror::Object> MonitorEnter(Thread* thread, |
| 80 | ObjPtr<mirror::Object> obj, |
| 81 | bool trylock) |
| 82 | EXCLUSIVE_LOCK_FUNCTION(obj.Ptr()) |
Mathieu Chartier | 2d096c9 | 2015-10-12 16:18:20 -0700 | [diff] [blame] | 83 | NO_THREAD_SAFETY_ANALYSIS |
| 84 | REQUIRES(!Roles::uninterruptible_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 85 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 86 | |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 87 | // NO_THREAD_SAFETY_ANALYSIS for mon->Unlock. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 88 | static bool MonitorExit(Thread* thread, ObjPtr<mirror::Object> obj) |
Mathieu Chartier | 2d096c9 | 2015-10-12 16:18:20 -0700 | [diff] [blame] | 89 | NO_THREAD_SAFETY_ANALYSIS |
| 90 | REQUIRES(!Roles::uninterruptible_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 91 | REQUIRES_SHARED(Locks::mutator_lock_) |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 92 | UNLOCK_FUNCTION(obj.Ptr()); |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 93 | |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 94 | static void Notify(Thread* self, ObjPtr<mirror::Object> obj) |
| 95 | REQUIRES_SHARED(Locks::mutator_lock_) { |
Ian Rogers | 13c479e | 2013-10-11 07:59:01 -0700 | [diff] [blame] | 96 | DoNotify(self, obj, false); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 97 | } |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 98 | static void NotifyAll(Thread* self, ObjPtr<mirror::Object> obj) |
| 99 | REQUIRES_SHARED(Locks::mutator_lock_) { |
Ian Rogers | 13c479e | 2013-10-11 07:59:01 -0700 | [diff] [blame] | 100 | DoNotify(self, obj, true); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 101 | } |
Ian Rogers | 0ef3bd2 | 2014-08-15 13:39:34 -0700 | [diff] [blame] | 102 | |
| 103 | // Object.wait(). Also called for class init. |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 104 | // NO_THREAD_SAFETY_ANALYSIS for mon->Wait. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 105 | static void Wait(Thread* self, |
| 106 | ObjPtr<mirror::Object> obj, |
| 107 | int64_t ms, |
| 108 | int32_t ns, |
Ian Rogers | 2dd0e2c | 2013-01-24 12:42:14 -0800 | [diff] [blame] | 109 | bool interruptShouldThrow, ThreadState why) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 110 | REQUIRES_SHARED(Locks::mutator_lock_) NO_THREAD_SAFETY_ANALYSIS; |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 111 | |
Andreas Gampe | f3ebcce | 2017-12-11 20:40:23 -0800 | [diff] [blame] | 112 | static ThreadState FetchState(const Thread* thread, |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 113 | /* out */ ObjPtr<mirror::Object>* monitor_object, |
Andreas Gampe | f3ebcce | 2017-12-11 20:40:23 -0800 | [diff] [blame] | 114 | /* out */ uint32_t* lock_owner_tid) |
| 115 | REQUIRES(!Locks::thread_suspend_count_lock_) |
| 116 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 4993bbc | 2013-01-10 15:41:25 -0800 | [diff] [blame] | 117 | |
Elliott Hughes | f950170 | 2013-01-11 11:22:27 -0800 | [diff] [blame] | 118 | // Used to implement JDWP's ThreadReference.CurrentContendedMonitor. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 119 | static ObjPtr<mirror::Object> GetContendedMonitor(Thread* thread) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 120 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | f950170 | 2013-01-11 11:22:27 -0800 | [diff] [blame] | 121 | |
Elliott Hughes | 4993bbc | 2013-01-10 15:41:25 -0800 | [diff] [blame] | 122 | // Calls 'callback' once for each lock held in the single stack frame represented by |
| 123 | // the current state of 'stack_visitor'. |
Andreas Gampe | 956a522 | 2014-08-16 13:41:10 -0700 | [diff] [blame] | 124 | // The abort_on_failure flag allows to not die when the state of the runtime is unorderly. This |
| 125 | // is necessary when we have already aborted but want to dump the stack as much as we can. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 126 | static void VisitLocks(StackVisitor* stack_visitor, |
| 127 | void (*callback)(ObjPtr<mirror::Object>, void*), |
| 128 | void* callback_context, |
| 129 | bool abort_on_failure = true) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 130 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 8e4aac5 | 2011-09-26 17:03:36 -0700 | [diff] [blame] | 131 | |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 132 | static bool IsValidLockWord(LockWord lock_word); |
Ian Rogers | 7dfb28c | 2013-08-22 08:18:36 -0700 | [diff] [blame] | 133 | |
Hiroshi Yamauchi | 4cba0d9 | 2014-05-21 21:10:23 -0700 | [diff] [blame] | 134 | template<ReadBarrierOption kReadBarrierOption = kWithReadBarrier> |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 135 | ObjPtr<mirror::Object> GetObject() REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 136 | |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 137 | void SetObject(ObjPtr<mirror::Object> object); |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 138 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 139 | // Provides no memory ordering guarantees. |
| 140 | Thread* GetOwner() const { |
| 141 | return owner_.load(std::memory_order_relaxed); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 142 | } |
| 143 | |
Mathieu Chartier | 4e6a31e | 2013-10-31 10:35:05 -0700 | [diff] [blame] | 144 | int32_t GetHashCode(); |
Mathieu Chartier | ad2541a | 2013-10-25 10:05:23 -0700 | [diff] [blame] | 145 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 146 | // Is the monitor currently locked? Debug only, provides no memory ordering guarantees. |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 147 | bool IsLocked() REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!monitor_lock_); |
Mathieu Chartier | ad2541a | 2013-10-25 10:05:23 -0700 | [diff] [blame] | 148 | |
Mathieu Chartier | 4e6a31e | 2013-10-31 10:35:05 -0700 | [diff] [blame] | 149 | bool HasHashCode() const { |
Orion Hodson | 88591fe | 2018-03-06 13:35:43 +0000 | [diff] [blame] | 150 | return hash_code_.load(std::memory_order_relaxed) != 0; |
Mathieu Chartier | 4e6a31e | 2013-10-31 10:35:05 -0700 | [diff] [blame] | 151 | } |
| 152 | |
Ian Rogers | ef7d42f | 2014-01-06 12:55:46 -0800 | [diff] [blame] | 153 | MonitorId GetMonitorId() const { |
| 154 | return monitor_id_; |
| 155 | } |
| 156 | |
Ian Rogers | 43c69cc | 2014-08-15 11:09:28 -0700 | [diff] [blame] | 157 | // Inflate the lock on obj. May fail to inflate for spurious reasons, always re-check. |
Mathieu Chartier | 0cd8135 | 2014-05-22 16:48:55 -0700 | [diff] [blame] | 158 | static void InflateThinLocked(Thread* self, Handle<mirror::Object> obj, LockWord lock_word, |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 159 | uint32_t hash_code) REQUIRES_SHARED(Locks::mutator_lock_); |
Mathieu Chartier | ad2541a | 2013-10-25 10:05:23 -0700 | [diff] [blame] | 160 | |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 161 | // Not exclusive because ImageWriter calls this during a Heap::VisitObjects() that |
| 162 | // does not allow a thread suspension in the middle. TODO: maybe make this exclusive. |
| 163 | // NO_THREAD_SAFETY_ANALYSIS for monitor->monitor_lock_. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 164 | static bool Deflate(Thread* self, ObjPtr<mirror::Object> obj) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 165 | REQUIRES_SHARED(Locks::mutator_lock_) NO_THREAD_SAFETY_ANALYSIS; |
Mathieu Chartier | 590fee9 | 2013-09-13 13:46:47 -0700 | [diff] [blame] | 166 | |
Hiroshi Yamauchi | e15ea08 | 2015-02-09 17:11:42 -0800 | [diff] [blame] | 167 | #ifndef __LP64__ |
| 168 | void* operator new(size_t size) { |
| 169 | // Align Monitor* as per the monitor ID field size in the lock word. |
Brian Carlstrom | c57ad20 | 2015-03-03 21:21:29 -0800 | [diff] [blame] | 170 | void* result; |
| 171 | int error = posix_memalign(&result, LockWord::kMonitorIdAlignment, size); |
| 172 | CHECK_EQ(error, 0) << strerror(error); |
| 173 | return result; |
Hiroshi Yamauchi | e15ea08 | 2015-02-09 17:11:42 -0800 | [diff] [blame] | 174 | } |
Christopher Ferris | 8a35405 | 2015-04-24 17:23:53 -0700 | [diff] [blame] | 175 | |
| 176 | void operator delete(void* ptr) { |
| 177 | free(ptr); |
| 178 | } |
Hiroshi Yamauchi | e15ea08 | 2015-02-09 17:11:42 -0800 | [diff] [blame] | 179 | #endif |
| 180 | |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 181 | private: |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 182 | Monitor(Thread* self, Thread* owner, ObjPtr<mirror::Object> obj, int32_t hash_code) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 183 | REQUIRES_SHARED(Locks::mutator_lock_); |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 184 | Monitor(Thread* self, Thread* owner, ObjPtr<mirror::Object> obj, int32_t hash_code, MonitorId id) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 185 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 186 | |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 187 | // Install the monitor into its object, may fail if another thread installs a different monitor |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 188 | // first. Monitor remains in the same logical state as before, i.e. held the same # of times. |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 189 | bool Install(Thread* self) |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 190 | REQUIRES(!monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 191 | REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 192 | |
Ian Rogers | 0ef3bd2 | 2014-08-15 13:39:34 -0700 | [diff] [blame] | 193 | // Links a thread into a monitor's wait set. The monitor lock must be held by the caller of this |
| 194 | // routine. |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 195 | void AppendToWaitSet(Thread* thread) REQUIRES(monitor_lock_); |
Ian Rogers | 0ef3bd2 | 2014-08-15 13:39:34 -0700 | [diff] [blame] | 196 | |
| 197 | // Unlinks a thread from a monitor's wait set. The monitor lock must be held by the caller of |
| 198 | // this routine. |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 199 | void RemoveFromWaitSet(Thread* thread) REQUIRES(monitor_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 200 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 201 | // Release the monitor lock and signal a waiting thread that has been notified and now needs the |
| 202 | // lock. Assumes the monitor lock is held exactly once, and the owner_ field has been reset to |
| 203 | // null. Caller may be suspended (Wait) or runnable (MonitorExit). |
| 204 | void SignalWaiterAndReleaseMonitorLock(Thread* self) RELEASE(monitor_lock_); |
Charles Munger | c665d63 | 2018-11-06 16:20:13 +0000 | [diff] [blame] | 205 | |
Ian Rogers | 0ef3bd2 | 2014-08-15 13:39:34 -0700 | [diff] [blame] | 206 | // Changes the shape of a monitor from thin to fat, preserving the internal lock state. The |
| 207 | // calling thread must own the lock or the owner must be suspended. There's a race with other |
| 208 | // threads inflating the lock, installing hash codes and spurious failures. The caller should |
| 209 | // re-read the lock word following the call. |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 210 | static void Inflate(Thread* self, Thread* owner, ObjPtr<mirror::Object> obj, int32_t hash_code) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 211 | REQUIRES_SHARED(Locks::mutator_lock_) |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 212 | NO_THREAD_SAFETY_ANALYSIS; // For m->Install(self) |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 213 | |
Andreas Gampe | 39b9811 | 2017-06-01 16:28:27 -0700 | [diff] [blame] | 214 | void LogContentionEvent(Thread* self, |
| 215 | uint32_t wait_ms, |
| 216 | uint32_t sample_percent, |
| 217 | ArtMethod* owner_method, |
| 218 | uint32_t owner_dex_pc) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 219 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | fc86162 | 2011-10-17 17:57:47 -0700 | [diff] [blame] | 220 | |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 221 | static void FailedUnlock(ObjPtr<mirror::Object> obj, |
Mathieu Chartier | 61b3cd4 | 2016-04-18 11:43:29 -0700 | [diff] [blame] | 222 | uint32_t expected_owner_thread_id, |
| 223 | uint32_t found_owner_thread_id, |
Brian Carlstrom | c57ad20 | 2015-03-03 21:21:29 -0800 | [diff] [blame] | 224 | Monitor* mon) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 225 | REQUIRES(!Locks::thread_list_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 226 | REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | 6d0b13e | 2012-02-07 09:25:29 -0800 | [diff] [blame] | 227 | |
Mathieu Chartier | 4b0ef1c | 2016-07-29 16:26:01 -0700 | [diff] [blame] | 228 | // Try to lock without blocking, returns true if we acquired the lock. |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 229 | // If spin is true, then we spin for a short period before failing. |
| 230 | bool TryLock(Thread* self, bool spin = false) |
| 231 | TRY_ACQUIRE(true, monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 232 | REQUIRES_SHARED(Locks::mutator_lock_); |
Mathieu Chartier | 4b0ef1c | 2016-07-29 16:26:01 -0700 | [diff] [blame] | 233 | |
Alex Light | 77fee87 | 2017-09-05 14:51:49 -0700 | [diff] [blame] | 234 | template<LockReason reason = LockReason::kForLock> |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 235 | void Lock(Thread* self) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 236 | ACQUIRE(monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 237 | REQUIRES_SHARED(Locks::mutator_lock_); |
Alex Light | 77fee87 | 2017-09-05 14:51:49 -0700 | [diff] [blame] | 238 | |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 239 | bool Unlock(Thread* thread) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 240 | RELEASE(monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 241 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 242 | |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 243 | static void DoNotify(Thread* self, ObjPtr<mirror::Object> obj, bool notify_all) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 244 | REQUIRES_SHARED(Locks::mutator_lock_) NO_THREAD_SAFETY_ANALYSIS; // For mon->Notify. |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 245 | |
| 246 | void Notify(Thread* self) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 247 | REQUIRES(monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 248 | REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 249 | |
| 250 | void NotifyAll(Thread* self) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 251 | REQUIRES(monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 252 | REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 253 | |
Mathieu Chartier | 0ffdc9c | 2016-04-19 13:46:03 -0700 | [diff] [blame] | 254 | static std::string PrettyContentionInfo(const std::string& owner_name, |
| 255 | pid_t owner_tid, |
Mathieu Chartier | 74b3c8f | 2016-04-15 19:11:45 -0700 | [diff] [blame] | 256 | ArtMethod* owners_method, |
| 257 | uint32_t owners_dex_pc, |
| 258 | size_t num_waiters) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 259 | REQUIRES_SHARED(Locks::mutator_lock_); |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 260 | |
Ian Rogers | 0ef3bd2 | 2014-08-15 13:39:34 -0700 | [diff] [blame] | 261 | // Wait on a monitor until timeout, interrupt, or notification. Used for Object.wait() and |
| 262 | // (somewhat indirectly) Thread.sleep() and Thread.join(). |
| 263 | // |
| 264 | // If another thread calls Thread.interrupt(), we throw InterruptedException and return |
| 265 | // immediately if one of the following are true: |
| 266 | // - blocked in wait(), wait(long), or wait(long, int) methods of Object |
| 267 | // - blocked in join(), join(long), or join(long, int) methods of Thread |
| 268 | // - blocked in sleep(long), or sleep(long, int) methods of Thread |
| 269 | // Otherwise, we set the "interrupted" flag. |
| 270 | // |
| 271 | // Checks to make sure that "ns" is in the range 0-999999 (i.e. fractions of a millisecond) and |
| 272 | // throws the appropriate exception if it isn't. |
| 273 | // |
| 274 | // The spec allows "spurious wakeups", and recommends that all code using Object.wait() do so in |
| 275 | // a loop. This appears to derive from concerns about pthread_cond_wait() on multiprocessor |
| 276 | // systems. Some commentary on the web casts doubt on whether these can/should occur. |
| 277 | // |
| 278 | // Since we're allowed to wake up "early", we clamp extremely long durations to return at the end |
| 279 | // of the 32-bit time epoch. |
Elliott Hughes | 4cd121e | 2013-01-07 17:35:41 -0800 | [diff] [blame] | 280 | void Wait(Thread* self, int64_t msec, int32_t nsec, bool interruptShouldThrow, ThreadState why) |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 281 | REQUIRES(monitor_lock_) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 282 | REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 283 | |
jeffhao | 33dc771 | 2011-11-09 17:54:24 -0800 | [diff] [blame] | 284 | // Translates the provided method and pc into its declaring class' source file and line number. |
Mathieu Chartier | 74b3c8f | 2016-04-15 19:11:45 -0700 | [diff] [blame] | 285 | static void TranslateLocation(ArtMethod* method, uint32_t pc, |
| 286 | const char** source_file, |
| 287 | int32_t* line_number) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 288 | REQUIRES_SHARED(Locks::mutator_lock_); |
jeffhao | 33dc771 | 2011-11-09 17:54:24 -0800 | [diff] [blame] | 289 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 290 | // Provides no memory ordering guarantees. |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 291 | uint32_t GetOwnerThreadId() REQUIRES(!monitor_lock_); |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 292 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 293 | // Set locking_method_ and locking_dex_pc_ corresponding to owner's current stack. |
| 294 | // owner is either self or suspended. |
| 295 | void SetLockingMethod(Thread* owner) REQUIRES(monitor_lock_) |
| 296 | REQUIRES_SHARED(Locks::mutator_lock_); |
| 297 | |
| 298 | // The same, but without checking for a proxy method. Currently requires owner == self. |
| 299 | void SetLockingMethodNoProxy(Thread* owner) REQUIRES(monitor_lock_) |
| 300 | REQUIRES_SHARED(Locks::mutator_lock_); |
| 301 | |
Andreas Gampe | c7ed09b | 2016-04-25 20:08:55 -0700 | [diff] [blame] | 302 | // Support for systrace output of monitor operations. |
| 303 | ALWAYS_INLINE static void AtraceMonitorLock(Thread* self, |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 304 | ObjPtr<mirror::Object> obj, |
Andreas Gampe | c7ed09b | 2016-04-25 20:08:55 -0700 | [diff] [blame] | 305 | bool is_wait) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 306 | REQUIRES_SHARED(Locks::mutator_lock_); |
Andreas Gampe | c7ed09b | 2016-04-25 20:08:55 -0700 | [diff] [blame] | 307 | static void AtraceMonitorLockImpl(Thread* self, |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 308 | ObjPtr<mirror::Object> obj, |
Andreas Gampe | c7ed09b | 2016-04-25 20:08:55 -0700 | [diff] [blame] | 309 | bool is_wait) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 310 | REQUIRES_SHARED(Locks::mutator_lock_); |
Andreas Gampe | c7ed09b | 2016-04-25 20:08:55 -0700 | [diff] [blame] | 311 | ALWAYS_INLINE static void AtraceMonitorUnlock(); |
| 312 | |
Elliott Hughes | fc86162 | 2011-10-17 17:57:47 -0700 | [diff] [blame] | 313 | static uint32_t lock_profiling_threshold_; |
Andreas Gampe | d0210e5 | 2017-06-23 13:38:09 -0700 | [diff] [blame] | 314 | static uint32_t stack_dump_lock_profiling_threshold_; |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 315 | static bool capture_method_eagerly_; |
Elliott Hughes | 32d6e1e | 2011-10-11 14:47:44 -0700 | [diff] [blame] | 316 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 317 | // Holding the monitor N times is represented by holding monitor_lock_ N times. |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 318 | Mutex monitor_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; |
Ian Rogers | 719d1a3 | 2014-03-06 12:13:39 -0800 | [diff] [blame] | 319 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 320 | // Pretend to unlock monitor lock. |
| 321 | void FakeUnlockMonitorLock() RELEASE(monitor_lock_) NO_THREAD_SAFETY_ANALYSIS {} |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 322 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 323 | // Number of threads either waiting on the condition or waiting on a contended |
| 324 | // monitor acquisition. Prevents deflation. |
| 325 | std::atomic<size_t> num_waiters_; |
Mathieu Chartier | 46bc778 | 2013-11-12 17:03:02 -0800 | [diff] [blame] | 326 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 327 | // Which thread currently owns the lock? monitor_lock_ only keeps the tid. |
| 328 | // Only set while holding monitor_lock_. Non-locking readers only use it to |
| 329 | // compare to self or for debugging. |
| 330 | std::atomic<Thread*> owner_; |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 331 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 332 | // Owner's recursive lock depth. Owner_ non-null, and lock_count_ == 0 ==> held once. |
| 333 | unsigned int lock_count_ GUARDED_BY(monitor_lock_); |
| 334 | |
| 335 | // Owner's recursive lock depth is given by monitor_lock_.GetDepth(). |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 336 | |
Hiroshi Yamauchi | 4cba0d9 | 2014-05-21 21:10:23 -0700 | [diff] [blame] | 337 | // What object are we part of. This is a weak root. Do not access |
| 338 | // this directly, use GetObject() to read it so it will be guarded |
| 339 | // by a read barrier. |
Hiroshi Yamauchi | 94f7b49 | 2014-07-22 18:08:23 -0700 | [diff] [blame] | 340 | GcRoot<mirror::Object> obj_; |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 341 | |
Brian Carlstrom | 4514d3c | 2011-10-21 17:01:31 -0700 | [diff] [blame] | 342 | // Threads currently waiting on this monitor. |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 343 | Thread* wait_set_ GUARDED_BY(monitor_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 344 | |
Charles Munger | c665d63 | 2018-11-06 16:20:13 +0000 | [diff] [blame] | 345 | // Threads that were waiting on this monitor, but are now contending on it. |
| 346 | Thread* wake_set_ GUARDED_BY(monitor_lock_); |
| 347 | |
Mathieu Chartier | 4e6a31e | 2013-10-31 10:35:05 -0700 | [diff] [blame] | 348 | // Stored object hash code, generated lazily by GetHashCode. |
| 349 | AtomicInteger hash_code_; |
Mathieu Chartier | ad2541a | 2013-10-25 10:05:23 -0700 | [diff] [blame] | 350 | |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 351 | // Data structure used to remember the method and dex pc of a recent holder of the |
| 352 | // lock. Used for tracing and contention reporting. Setting these is expensive, since it |
| 353 | // involves a partial stack walk. We set them only as follows, to minimize the cost: |
| 354 | // - If tracing is enabled, they are needed immediately when we first notice contention, so we |
| 355 | // set them unconditionally when a monitor is acquired. |
| 356 | // - If contention reporting is enabled, we use the lock_owner_request_ field to have the |
| 357 | // contending thread request them. The current owner then sets them when releasing the monitor, |
| 358 | // making them available when the contending thread acquires the monitor. |
Orion Hodson | d1fab54 | 2020-07-27 15:07:41 +0100 | [diff] [blame] | 359 | // - If tracing and contention reporting are enabled, we do both. This usually prevents us from |
| 360 | // switching between reporting the end and beginning of critical sections for contention logging |
| 361 | // when tracing is enabled. We expect that tracing overhead is normally much higher than for |
| 362 | // contention logging, so the added cost should be small. It also minimizes glitches when |
| 363 | // enabling and disabling traces. |
Hans Boehm | 65c18a2 | 2020-01-03 23:37:13 +0000 | [diff] [blame] | 364 | // We're tolerant of missing information. E.g. when tracing is initially turned on, we may |
| 365 | // not have the lock holder information if the holder acquired the lock with tracing off. |
| 366 | // |
| 367 | // We make this data unconditionally atomic; for contention logging all accesses are in fact |
| 368 | // protected by the monitor, but for tracing, reads are not. Writes are always |
| 369 | // protected by the monitor. |
| 370 | // |
| 371 | // The fields are always accessed without memory ordering. We store a checksum, and reread if |
| 372 | // the checksum doesn't correspond to the values. This results in values that are correct with |
| 373 | // very high probability, but not certainty. |
| 374 | // |
| 375 | // If we need lock_owner information for a certain thread for contenion logging, we store its |
| 376 | // tid in lock_owner_request_. To satisfy the request, we store lock_owner_tid_, |
| 377 | // lock_owner_method_, and lock_owner_dex_pc_ and the corresponding checksum while holding the |
| 378 | // monitor. |
| 379 | // |
| 380 | // At all times, either lock_owner_ is zero, the checksum is valid, or a thread is actively |
| 381 | // in the process of establishing one of those states. Only one thread at a time can be actively |
| 382 | // establishing such a state, since writes are protected by the monitor. |
| 383 | std::atomic<Thread*> lock_owner_; // *lock_owner_ may no longer exist! |
| 384 | std::atomic<ArtMethod*> lock_owner_method_; |
| 385 | std::atomic<uint32_t> lock_owner_dex_pc_; |
| 386 | std::atomic<uintptr_t> lock_owner_sum_; |
| 387 | |
| 388 | // Request lock owner save method and dex_pc. Written asynchronously. |
| 389 | std::atomic<Thread*> lock_owner_request_; |
| 390 | |
| 391 | // Compute method, dex pc, and tid "checksum". |
| 392 | uintptr_t LockOwnerInfoChecksum(ArtMethod* m, uint32_t dex_pc, Thread* t); |
| 393 | |
| 394 | // Set owning method, dex pc, and tid. owner_ field is set and points to current thread. |
| 395 | void SetLockOwnerInfo(ArtMethod* method, uint32_t dex_pc, Thread* t) |
| 396 | REQUIRES(monitor_lock_); |
| 397 | |
| 398 | // Get owning method and dex pc for the given thread, if available. |
| 399 | void GetLockOwnerInfo(/*out*/ArtMethod** method, /*out*/uint32_t* dex_pc, Thread* t); |
| 400 | |
| 401 | // Do the same, while holding the monitor. There are no concurrent updates. |
| 402 | void GetLockOwnerInfoLocked(/*out*/ArtMethod** method, /*out*/uint32_t* dex_pc, |
| 403 | uint32_t thread_id) |
| 404 | REQUIRES(monitor_lock_); |
| 405 | |
| 406 | // We never clear lock_owner method and dex pc. Since it often reflects |
| 407 | // ownership when we last detected contention, it may be inconsistent with owner_ |
| 408 | // and not 100% reliable. For lock contention monitoring, in the absence of tracing, |
| 409 | // there is a small risk that the current owner may finish before noticing the request, |
| 410 | // or the information will be overwritten by another intervening request and monitor |
| 411 | // release, so it's also not 100% reliable. But if we report information at all, it |
| 412 | // should generally (modulo accidental checksum matches) pertain to to an acquisition of the |
| 413 | // right monitor by the right thread, so it's extremely unlikely to be seriously misleading. |
| 414 | // Since we track threads by a pointer to the Thread structure, there is a small chance we may |
| 415 | // confuse threads allocated at the same exact address, if a contending thread dies before |
| 416 | // we inquire about it. |
| 417 | |
| 418 | // Check for and act on a pending lock_owner_request_ |
| 419 | void CheckLockOwnerRequest(Thread* self) |
| 420 | REQUIRES(monitor_lock_) REQUIRES_SHARED(Locks::mutator_lock_); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 421 | |
wangguibo | e1484e9 | 2021-04-24 11:27:06 +0800 | [diff] [blame^] | 422 | void MaybeEnableTimeout() REQUIRES(Locks::mutator_lock_); |
| 423 | |
Ian Rogers | ef7d42f | 2014-01-06 12:55:46 -0800 | [diff] [blame] | 424 | // The denser encoded version of this monitor as stored in the lock word. |
| 425 | MonitorId monitor_id_; |
| 426 | |
Andreas Gampe | 7424081 | 2014-04-17 10:35:09 -0700 | [diff] [blame] | 427 | #ifdef __LP64__ |
| 428 | // Free list for monitor pool. |
| 429 | Monitor* next_free_ GUARDED_BY(Locks::allocated_monitor_ids_lock_); |
| 430 | #endif |
| 431 | |
Elliott Hughes | f327e07 | 2013-01-09 16:01:26 -0800 | [diff] [blame] | 432 | friend class MonitorInfo; |
Brian Carlstrom | 4514d3c | 2011-10-21 17:01:31 -0700 | [diff] [blame] | 433 | friend class MonitorList; |
Andreas Gampe | 7424081 | 2014-04-17 10:35:09 -0700 | [diff] [blame] | 434 | friend class MonitorPool; |
Ian Rogers | 2dd0e2c | 2013-01-24 12:42:14 -0800 | [diff] [blame] | 435 | friend class mirror::Object; |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 436 | DISALLOW_COPY_AND_ASSIGN(Monitor); |
| 437 | }; |
| 438 | |
| 439 | class MonitorList { |
| 440 | public: |
| 441 | MonitorList(); |
| 442 | ~MonitorList(); |
| 443 | |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 444 | void Add(Monitor* m) REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!monitor_list_lock_); |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 445 | |
Mathieu Chartier | 9750995 | 2015-07-13 14:35:43 -0700 | [diff] [blame] | 446 | void SweepMonitorList(IsMarkedVisitor* visitor) |
Andreas Gampe | bdf7f1c | 2016-08-30 16:38:47 -0700 | [diff] [blame] | 447 | REQUIRES(!monitor_list_lock_) REQUIRES_SHARED(Locks::mutator_lock_); |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 448 | void DisallowNewMonitors() REQUIRES(!monitor_list_lock_); |
| 449 | void AllowNewMonitors() REQUIRES(!monitor_list_lock_); |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 450 | void BroadcastForNewMonitors() REQUIRES(!monitor_list_lock_); |
Mathieu Chartier | 48ab687 | 2014-06-24 11:21:59 -0700 | [diff] [blame] | 451 | // Returns how many monitors were deflated. |
Mathieu Chartier | 9044347 | 2015-07-16 20:32:27 -0700 | [diff] [blame] | 452 | size_t DeflateMonitors() REQUIRES(!monitor_list_lock_) REQUIRES(Locks::mutator_lock_); |
Hans Boehm | 6fe97e0 | 2016-05-04 18:35:57 -0700 | [diff] [blame] | 453 | size_t Size() REQUIRES(!monitor_list_lock_); |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 454 | |
Mathieu Chartier | bad0267 | 2014-08-25 13:08:22 -0700 | [diff] [blame] | 455 | typedef std::list<Monitor*, TrackingAllocator<Monitor*, kAllocatorTagMonitorList>> Monitors; |
| 456 | |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 457 | private: |
Ian Rogers | 5c597c6 | 2014-04-17 16:08:07 -0700 | [diff] [blame] | 458 | // During sweeping we may free an object and on a separate thread have an object created using |
| 459 | // the newly freed memory. That object may then have its lock-word inflated and a monitor created. |
| 460 | // If we allow new monitor registration during sweeping this monitor may be incorrectly freed as |
| 461 | // the object wasn't marked when sweeping began. |
Mathieu Chartier | c11d9b8 | 2013-09-19 10:01:59 -0700 | [diff] [blame] | 462 | bool allow_new_monitors_ GUARDED_BY(monitor_list_lock_); |
Ian Rogers | 00f7d0e | 2012-07-19 15:28:27 -0700 | [diff] [blame] | 463 | Mutex monitor_list_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; |
Mathieu Chartier | c11d9b8 | 2013-09-19 10:01:59 -0700 | [diff] [blame] | 464 | ConditionVariable monitor_add_condition_ GUARDED_BY(monitor_list_lock_); |
Mathieu Chartier | bad0267 | 2014-08-25 13:08:22 -0700 | [diff] [blame] | 465 | Monitors list_ GUARDED_BY(monitor_list_lock_); |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 466 | |
Ian Rogers | 7dfb28c | 2013-08-22 08:18:36 -0700 | [diff] [blame] | 467 | friend class Monitor; |
Elliott Hughes | c33a32b | 2011-10-11 18:18:07 -0700 | [diff] [blame] | 468 | DISALLOW_COPY_AND_ASSIGN(MonitorList); |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 469 | }; |
| 470 | |
Elliott Hughes | f327e07 | 2013-01-09 16:01:26 -0800 | [diff] [blame] | 471 | // Collects information about the current state of an object's monitor. |
| 472 | // This is very unsafe, and must only be called when all threads are suspended. |
| 473 | // For use only by the JDWP implementation. |
| 474 | class MonitorInfo { |
| 475 | public: |
Andreas Gampe | d9911ee | 2017-03-27 13:27:24 -0700 | [diff] [blame] | 476 | MonitorInfo() : owner_(nullptr), entry_count_(0) {} |
Mathieu Chartier | f1d666e | 2015-09-03 16:13:34 -0700 | [diff] [blame] | 477 | MonitorInfo(const MonitorInfo&) = default; |
| 478 | MonitorInfo& operator=(const MonitorInfo&) = default; |
Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 479 | explicit MonitorInfo(ObjPtr<mirror::Object> o) REQUIRES(Locks::mutator_lock_); |
Elliott Hughes | f327e07 | 2013-01-09 16:01:26 -0800 | [diff] [blame] | 480 | |
Ian Rogers | d9c4fc9 | 2013-10-01 19:45:43 -0700 | [diff] [blame] | 481 | Thread* owner_; |
| 482 | size_t entry_count_; |
| 483 | std::vector<Thread*> waiters_; |
Elliott Hughes | f327e07 | 2013-01-09 16:01:26 -0800 | [diff] [blame] | 484 | }; |
| 485 | |
Elliott Hughes | 5f79133 | 2011-09-15 17:45:30 -0700 | [diff] [blame] | 486 | } // namespace art |
| 487 | |
Brian Carlstrom | fc0e321 | 2013-07-17 14:40:12 -0700 | [diff] [blame] | 488 | #endif // ART_RUNTIME_MONITOR_H_ |