Line data    Source code

       1             : // Copyright 2012 the V8 project authors. All rights reserved.
       2             : // Use of this source code is governed by a BSD-style license that can be
       3             : // found in the LICENSE file.
       4             : 
       5             : #ifndef V8_V8THREADS_H_
       6             : #define V8_V8THREADS_H_
       7             : 
       8             : #include "src/isolate.h"
       9             : 
      10             : namespace v8 {
      11             : namespace internal {
      12             : 
      13             : class RootVisitor;
      14             : class ThreadLocalTop;
      15             : 
      16             : class ThreadState {
      17             :  public:
      18             :   // Returns nullptr after the last one.
      19             :   ThreadState* Next();
      20             : 
      21             :   enum List {FREE_LIST, IN_USE_LIST};
      22             : 
      23             :   void LinkInto(List list);
      24             :   void Unlink();
      25             : 
      26             :   // Id of thread.
      27       50644 :   void set_id(ThreadId id) { id_ = id; }
      28             :   ThreadId id() { return id_; }
      29             : 
      30             :   // Should the thread be terminated when it is restored?
      31             :   bool terminate_on_restore() { return terminate_on_restore_; }
      32             :   void set_terminate_on_restore(bool terminate_on_restore) {
      33           0 :     terminate_on_restore_ = terminate_on_restore;
      34             :   }
      35             : 
      36             :   // Get data area for archiving a thread.
      37             :   char* data() { return data_; }
      38             : 
      39             :  private:
      40             :   explicit ThreadState(ThreadManager* thread_manager);
      41             :   ~ThreadState();
      42             : 
      43             :   void AllocateSpace();
      44             : 
      45             :   ThreadId id_;
      46             :   bool terminate_on_restore_;
      47             :   char* data_;
      48             :   ThreadState* next_;
      49             :   ThreadState* previous_;
      50             : 
      51             :   ThreadManager* thread_manager_;
      52             : 
      53             :   friend class ThreadManager;
      54             : };
      55             : 
      56       76351 : class ThreadVisitor {
      57             :  public:
      58             :   // ThreadLocalTop may be only available during this call.
      59             :   virtual void VisitThread(Isolate* isolate, ThreadLocalTop* top) = 0;
      60             : 
      61             :  protected:
      62       76351 :   virtual ~ThreadVisitor() = default;
      63             : };
      64             : 
      65             : class ThreadManager {
      66             :  public:
      67             :   void Lock();
      68             :   void Unlock();
      69             : 
      70             :   void InitThread(const ExecutionAccess&);
      71             :   void ArchiveThread();
      72             :   bool RestoreThread();
      73             :   void FreeThreadResources();
      74             :   bool IsArchived();
      75             : 
      76             :   void Iterate(RootVisitor* v);
      77             :   void IterateArchivedThreads(ThreadVisitor* v);
      78       70620 :   bool IsLockedByCurrentThread() {
      79      141241 :     return mutex_owner_.Equals(ThreadId::Current());
      80             :   }
      81             : 
      82             :   ThreadId CurrentId();
      83             : 
      84             :   void TerminateExecution(ThreadId thread_id);
      85             : 
      86             :   // Iterate over in-use states.
      87             :   ThreadState* FirstThreadStateInUse();
      88             :   ThreadState* GetFreeThreadState();
      89             : 
      90             :  private:
      91             :   explicit ThreadManager(Isolate* isolate);
      92             :   ~ThreadManager();
      93             : 
      94             :   void DeleteThreadStateList(ThreadState* anchor);
      95             : 
      96             :   void EagerlyArchiveThread();
      97             : 
      98             :   base::Mutex mutex_;
      99             :   ThreadId mutex_owner_;
     100             :   ThreadId lazily_archived_thread_;
     101             :   ThreadState* lazily_archived_thread_state_;
     102             : 
     103             :   // In the following two lists there is always at least one object on the list.
     104             :   // The first object is a flying anchor that is only there to simplify linking
     105             :   // and unlinking.
     106             :   // Head of linked list of free states.
     107             :   ThreadState* free_anchor_;
     108             :   // Head of linked list of states in use.
     109             :   ThreadState* in_use_anchor_;
     110             : 
     111             :   Isolate* isolate_;
     112             : 
     113             :   friend class Isolate;
     114             :   friend class ThreadState;
     115             : };
     116             : 
     117             : 
     118             : }  // namespace internal
     119             : }  // namespace v8
     120             : 
     121             : #endif  // V8_V8THREADS_H_