/* * Copyright (C) 2011 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef ART_RUNTIME_THREAD_LIST_H_ #define ART_RUNTIME_THREAD_LIST_H_ #include "base/histogram.h" #include "base/mutex.h" #include "gc_root.h" #include "jni.h" #include "object_callbacks.h" #include #include namespace art { namespace gc { namespace collector { class GarbageCollector; } // namespac collector } // namespace gc class Closure; class Thread; class TimingLogger; class ThreadList { public: static const uint32_t kMaxThreadId = 0xFFFF; static const uint32_t kInvalidThreadId = 0; static const uint32_t kMainThreadId = 1; explicit ThreadList(); ~ThreadList(); void DumpForSigQuit(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::mutator_lock_); // For thread suspend timeout dumps. void Dump(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); pid_t GetLockOwner(); // For SignalCatcher. // Thread suspension support. void ResumeAll() UNLOCK_FUNCTION(Locks::mutator_lock_) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); void Resume(Thread* thread, bool for_debugger = false) LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_); // Suspends all threads and gets exclusive access to the mutator_lock_. // If long suspend is true, then other people who try to suspend will never timeout. Long suspend // is currenly used for hprof since large heaps take a long time. void SuspendAll(const char* cause, bool long_suspend = false) EXCLUSIVE_LOCK_FUNCTION(Locks::mutator_lock_) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Suspend a thread using a peer, typically used by the debugger. Returns the thread on success, // else null. The peer is used to identify the thread to avoid races with the thread terminating. // If the thread should be suspended then value of request_suspension should be true otherwise // the routine will wait for a previous suspend request. If the suspension times out then *timeout // is set to true. Thread* SuspendThreadByPeer(jobject peer, bool request_suspension, bool debug_suspension, bool* timed_out) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Suspend a thread using its thread id, typically used by lock/monitor inflation. Returns the // thread on success else null. The thread id is used to identify the thread to avoid races with // the thread terminating. Note that as thread ids are recycled this may not suspend the expected // thread, that may be terminating. If the suspension times out then *timeout is set to true. Thread* SuspendThreadByThreadId(uint32_t thread_id, bool debug_suspension, bool* timed_out) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Find an already suspended thread (or self) by its id. Thread* FindThreadByThreadId(uint32_t thin_lock_id); // Run a checkpoint on threads, running threads are not suspended but run the checkpoint inside // of the suspend check. Returns how many checkpoints we should expect to run. size_t RunCheckpoint(Closure* checkpoint_function) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); size_t RunCheckpointOnRunnableThreads(Closure* checkpoint_function) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Flip thread roots from from-space refs to to-space refs. Used by // the concurrent copying collector. size_t FlipThreadRoots(Closure* thread_flip_visitor, Closure* flip_callback, gc::collector::GarbageCollector* collector) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Suspends all threads void SuspendAllForDebugger() LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); void SuspendSelfForDebugger() LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_); // Resume all threads void ResumeAllForDebugger() LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); void UndoDebuggerSuspensions() LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); // Iterates over all the threads. void ForEach(void (*callback)(Thread*, void*), void* context) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_); // Add/remove current thread from list. void Register(Thread* self) EXCLUSIVE_LOCKS_REQUIRED(Locks::runtime_shutdown_lock_) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_); void Unregister(Thread* self) LOCKS_EXCLUDED(Locks::mutator_lock_, Locks::thread_list_lock_); void VisitRoots(RootVisitor* visitor) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); // Return a copy of the thread list. std::list GetList() EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_) { return list_; } void DumpNativeStacks(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_); private: uint32_t AllocThreadId(Thread* self); void ReleaseThreadId(Thread* self, uint32_t id) LOCKS_EXCLUDED(Locks::allocated_thread_ids_lock_); bool Contains(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_); bool Contains(pid_t tid) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_); void DumpUnattachedThreads(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_); void SuspendAllDaemonThreads() LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); void WaitForOtherNonDaemonThreadsToExit() LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); void AssertThreadsAreSuspended(Thread* self, Thread* ignore1, Thread* ignore2 = nullptr) LOCKS_EXCLUDED(Locks::thread_list_lock_, Locks::thread_suspend_count_lock_); std::bitset allocated_ids_ GUARDED_BY(Locks::allocated_thread_ids_lock_); // The actual list of all threads. std::list list_ GUARDED_BY(Locks::thread_list_lock_); // Ongoing suspend all requests, used to ensure threads added to list_ respect SuspendAll. int suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_); int debug_suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_); // Number of threads unregistering, ~ThreadList blocks until this hits 0. int unregistering_count_ GUARDED_BY(Locks::thread_list_lock_); // Thread suspend time histogram. Only modified when all the threads are suspended, so guarding // by mutator lock ensures no thread can read when another thread is modifying it. Histogram suspend_all_historam_ GUARDED_BY(Locks::mutator_lock_); // Whether or not the current thread suspension is long. bool long_suspend_; friend class Thread; DISALLOW_COPY_AND_ASSIGN(ThreadList); }; } // namespace art #endif // ART_RUNTIME_THREAD_LIST_H_