1 // Copyright 2008 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
6 // * Redistributions of source code must retain the above copyright
7 // notice, this list of conditions and the following disclaimer.
8 // * Redistributions in binary form must reproduce the above
9 // copyright notice, this list of conditions and the following
10 // disclaimer in the documentation and/or other materials provided
11 // with the distribution.
12 // * Neither the name of Google Inc. nor the names of its
13 // contributors may be used to endorse or promote products derived
14 // from this software without specific prior written permission.
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #ifndef V8_V8THREADS_H_
29 #define V8_V8THREADS_H_
37 // Returns NULL after the last one.
40 enum List {FREE_LIST, IN_USE_LIST};
42 void LinkInto(List list);
46 void set_id(ThreadId id) { id_ = id; }
47 ThreadId id() { return id_; }
49 // Should the thread be terminated when it is restored?
50 bool terminate_on_restore() { return terminate_on_restore_; }
51 void set_terminate_on_restore(bool terminate_on_restore) {
52 terminate_on_restore_ = terminate_on_restore;
55 // Get data area for archiving a thread.
56 char* data() { return data_; }
59 explicit ThreadState(ThreadManager* thread_manager);
64 bool terminate_on_restore_;
67 ThreadState* previous_;
69 ThreadManager* thread_manager_;
71 friend class ThreadManager;
75 // Defined in isolate.h.
81 // ThreadLocalTop may be only available during this call.
82 virtual void VisitThread(Isolate* isolate, ThreadLocalTop* top) = 0;
85 virtual ~ThreadVisitor() {}
96 void FreeThreadResources();
99 void Iterate(ObjectVisitor* v);
100 void IterateArchivedThreads(ThreadVisitor* v);
101 bool IsLockedByCurrentThread() {
102 return mutex_owner_.Equals(ThreadId::Current());
105 ThreadId CurrentId();
107 void TerminateExecution(ThreadId thread_id);
109 // Iterate over in-use states.
110 ThreadState* FirstThreadStateInUse();
111 ThreadState* GetFreeThreadState();
117 void EagerlyArchiveThread();
120 ThreadId mutex_owner_;
121 ThreadId lazily_archived_thread_;
122 ThreadState* lazily_archived_thread_state_;
124 // In the following two lists there is always at least one object on the list.
125 // The first object is a flying anchor that is only there to simplify linking
127 // Head of linked list of free states.
128 ThreadState* free_anchor_;
129 // Head of linked list of states in use.
130 ThreadState* in_use_anchor_;
134 friend class Isolate;
135 friend class ThreadState;
139 // The ContextSwitcher thread is used to schedule regular preemptions to
140 // multiple running V8 threads. Generally it is necessary to call
141 // StartPreemption if there is more than one thread running. If not, a single
142 // JavaScript can take full control of V8 and not allow other threads to run.
143 class ContextSwitcher: public Thread {
145 // Set the preemption interval for the ContextSwitcher thread.
146 static void StartPreemption(int every_n_ms);
148 // Stop sending preemption requests to threads.
149 static void StopPreemption();
151 // Preempted thread needs to call back to the ContextSwitcher to acknowledge
152 // the handling of a preemption request.
153 static void PreemptionReceived();
156 ContextSwitcher(Isolate* isolate, int every_n_ms);
158 Isolate* isolate() const { return isolate_; }
167 } } // namespace v8::internal
169 #endif // V8_V8THREADS_H_