thread_list.h revision 59952167697d3b7e6655cb76d087a809c4f615d8 
1/*
2 * Copyright (C) 2011 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_THREAD_LIST_H_
18#define ART_RUNTIME_THREAD_LIST_H_
19
20#include "base/mutex.h"
21#include "jni.h"
22#include "object_callbacks.h"
23
24#include <bitset>
25#include <list>
26
27namespace art {
28class Closure;
29class Thread;
30class TimingLogger;
31
32class ThreadList {
33 public:
34  static const uint32_t kMaxThreadId = 0xFFFF;
35  static const uint32_t kInvalidThreadId = 0;
36  static const uint32_t kMainThreadId = 1;
37
38  explicit ThreadList();
39  ~ThreadList();
40
41  void DumpForSigQuit(std::ostream& os)
42      LOCKS_EXCLUDED(Locks::thread_list_lock_)
43      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
44  void DumpLocked(std::ostream& os)  // For thread suspend timeout dumps.
45      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_)
46      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
47  pid_t GetLockOwner();  // For SignalCatcher.
48
49  // Thread suspension support.
50  void ResumeAll()
51      UNLOCK_FUNCTION(Locks::mutator_lock_)
52      LOCKS_EXCLUDED(Locks::thread_list_lock_,
53                     Locks::thread_suspend_count_lock_);
54  void Resume(Thread* thread, bool for_debugger = false)
55      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_);
56
57  // Suspends all threads and gets exclusive access to the mutator_lock_.
58  void SuspendAll()
59      EXCLUSIVE_LOCK_FUNCTION(Locks::mutator_lock_)
60      LOCKS_EXCLUDED(Locks::thread_list_lock_,
61                     Locks::thread_suspend_count_lock_);
62
63
64  // Suspend a thread using a peer, typically used by the debugger. Returns the thread on success,
65  // else NULL. The peer is used to identify the thread to avoid races with the thread terminating.
66  // If the thread should be suspended then value of request_suspension should be true otherwise
67  // the routine will wait for a previous suspend request. If the suspension times out then *timeout
68  // is set to true.
69  static Thread* SuspendThreadByPeer(jobject peer, bool request_suspension, bool debug_suspension,
70                                     bool* timed_out)
71      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_suspend_thread_lock_)
72      LOCKS_EXCLUDED(Locks::mutator_lock_,
73                     Locks::thread_list_lock_,
74                     Locks::thread_suspend_count_lock_);
75
76  // Suspend a thread using its thread id, typically used by lock/monitor inflation. Returns the
77  // thread on success else NULL. The thread id is used to identify the thread to avoid races with
78  // the thread terminating. Note that as thread ids are recycled this may not suspend the expected
79  // thread, that may be terminating. If the suspension times out then *timeout is set to true.
80  Thread* SuspendThreadByThreadId(uint32_t thread_id, bool debug_suspension, bool* timed_out)
81      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_suspend_thread_lock_)
82      LOCKS_EXCLUDED(Locks::mutator_lock_,
83                     Locks::thread_list_lock_,
84                     Locks::thread_suspend_count_lock_);
85
86  // Find an already suspended thread (or self) by its id.
87  Thread* FindThreadByThreadId(uint32_t thin_lock_id);
88
89  // Run a checkpoint on threads, running threads are not suspended but run the checkpoint inside
90  // of the suspend check. Returns how many checkpoints we should expect to run.
91  size_t RunCheckpoint(Closure* checkpoint_function)
92      LOCKS_EXCLUDED(Locks::thread_list_lock_,
93                     Locks::thread_suspend_count_lock_);
94
95  size_t RunCheckpointOnRunnableThreads(Closure* checkpoint_function)
96      LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_);
97
98  // Suspends all threads
99  void SuspendAllForDebugger()
100      LOCKS_EXCLUDED(Locks::mutator_lock_,
101                     Locks::thread_list_lock_,
102                     Locks::thread_suspend_count_lock_);
103
104  void SuspendSelfForDebugger()
105      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_);
106
107  void UndoDebuggerSuspensions()
108      LOCKS_EXCLUDED(Locks::thread_list_lock_,
109                     Locks::thread_suspend_count_lock_);
110
111  // Iterates over all the threads.
112  void ForEach(void (*callback)(Thread*, void*), void* context)
113      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
114
115  // Add/remove current thread from list.
116  void Register(Thread* self)
117      EXCLUSIVE_LOCKS_REQUIRED(Locks::runtime_shutdown_lock_)
118      LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_);
119  void Unregister(Thread* self) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_);
120
121  void VisitRoots(RootCallback* callback, void* arg) const
122      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
123
124  void VerifyRoots(VerifyRootCallback* callback, void* arg) const
125      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
126
127  // Return a copy of the thread list.
128  std::list<Thread*> GetList() EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_) {
129    return list_;
130  }
131
132  void DumpNativeStacks(std::ostream& os)
133      LOCKS_EXCLUDED(Locks::thread_list_lock_);
134
135 private:
136  uint32_t AllocThreadId(Thread* self);
137  void ReleaseThreadId(Thread* self, uint32_t id) LOCKS_EXCLUDED(Locks::allocated_thread_ids_lock_);
138
139  bool Contains(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
140  bool Contains(pid_t tid) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
141
142  void DumpUnattachedThreads(std::ostream& os)
143      LOCKS_EXCLUDED(Locks::thread_list_lock_);
144
145  void SuspendAllDaemonThreads()
146      LOCKS_EXCLUDED(Locks::thread_list_lock_,
147                     Locks::thread_suspend_count_lock_);
148  void WaitForOtherNonDaemonThreadsToExit()
149      LOCKS_EXCLUDED(Locks::thread_list_lock_,
150                     Locks::thread_suspend_count_lock_);
151
152  void AssertThreadsAreSuspended(Thread* self, Thread* ignore1, Thread* ignore2 = NULL)
153      LOCKS_EXCLUDED(Locks::thread_list_lock_,
154                     Locks::thread_suspend_count_lock_);
155
156  std::bitset<kMaxThreadId> allocated_ids_ GUARDED_BY(Locks::allocated_thread_ids_lock_);
157
158  // The actual list of all threads.
159  std::list<Thread*> list_ GUARDED_BY(Locks::thread_list_lock_);
160
161  // Ongoing suspend all requests, used to ensure threads added to list_ respect SuspendAll.
162  int suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
163  int debug_suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
164
165  // Signaled when threads terminate. Used to determine when all non-daemons have terminated.
166  ConditionVariable thread_exit_cond_ GUARDED_BY(Locks::thread_list_lock_);
167
168  friend class Thread;
169
170  DISALLOW_COPY_AND_ASSIGN(ThreadList);
171};
172
173}  // namespace art
174
175#endif  // ART_RUNTIME_THREAD_LIST_H_
176