• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
27 namespace art {
28 class Closure;
29 class Thread;
30 class TimingLogger;
31 
32 class 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   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.
GetList()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