1 /*
   2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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  23  */
  24 
  25 #ifndef SHARE_VM_RUNTIME_OSTHREAD_HPP
  26 #define SHARE_VM_RUNTIME_OSTHREAD_HPP
  27 
  28 #include "runtime/frame.hpp"
  29 #include "runtime/handles.hpp"
  30 #include "runtime/javaFrameAnchor.hpp"
  31 #include "runtime/objectMonitor.hpp"
  32 #include "utilities/top.hpp"
  33 
  34 // The OSThread class holds OS-specific thread information.  It is equivalent
  35 // to the sys_thread_t structure of the classic JVM implementation.
  36 
  37 // The thread states represented by the ThreadState values are platform-specific
  38 // and are likely to be only approximate, because most OSes don't give you access
  39 // to precise thread state information.
  40 
  41 // Note: the ThreadState is legacy code and is not correctly implemented.
  42 // Uses of ThreadState need to be replaced by the state in the JavaThread.
  43 
  44 enum ThreadState {
  45   ALLOCATED,                    // Memory has been allocated but not initialized
  46   INITIALIZED,                  // The thread has been initialized but yet started
  47   RUNNABLE,                     // Has been started and is runnable, but not necessarily running
  48   MONITOR_WAIT,                 // Waiting on a contended monitor lock
  49   CONDVAR_WAIT,                 // Waiting on a condition variable
  50   OBJECT_WAIT,                  // Waiting on an Object.wait() call
  51   BREAKPOINTED,                 // Suspended at breakpoint
  52   SLEEPING,                     // Thread.sleep()
  53   ZOMBIE                        // All done, but not reclaimed yet
  54 };
  55 
  56 // I'd make OSThread a ValueObj embedded in Thread to avoid an indirection, but
  57 // the assembler test in java.cpp expects that it can install the OSThread of
  58 // the main thread into its own Thread at will.
  59 
  60 
  61 class OSThread: public CHeapObj {
  62   friend class VMStructs;
  63  private:
  64   //void* _start_proc;            // Thread start routine
  65   OSThreadStartFunc _start_proc;  // Thread start routine
  66   void* _start_parm;              // Thread start routine parameter
  67   volatile ThreadState _state;    // Thread state *hint*
  68   volatile jint _interrupted;     // Thread.isInterrupted state
  69 
  70   // Note:  _interrupted must be jint, so that Java intrinsics can access it.
  71   // The value stored there must be either 0 or 1.  It must be possible
  72   // for Java to emulate Thread.currentThread().isInterrupted() by performing
  73   // the double indirection Thread::current()->_osthread->_interrupted.
  74 
  75   // Methods
  76  public:
  77   void set_state(ThreadState state)                { _state = state; }
  78   ThreadState get_state()                          { return _state; }
  79 
  80   // Constructor
  81   OSThread(OSThreadStartFunc start_proc, void* start_parm);
  82 
  83   // Destructor
  84   ~OSThread();
  85 
  86   // Accessors
  87   OSThreadStartFunc start_proc() const              { return _start_proc; }
  88   void set_start_proc(OSThreadStartFunc start_proc) { _start_proc = start_proc; }
  89   void* start_parm() const                          { return _start_parm; }
  90   void set_start_parm(void* start_parm)             { _start_parm = start_parm; }
  91 
  92   volatile bool interrupted() const                 { return _interrupted != 0; }
  93   void set_interrupted(bool z)                      { _interrupted = z ? 1 : 0; }
  94 
  95   // Printing
  96   void print_on(outputStream* st) const;
  97   void print() const                                { print_on(tty); }
  98 
  99   // For java intrinsics:
 100   static ByteSize interrupted_offset()            { return byte_offset_of(OSThread, _interrupted); }
 101 
 102   // Platform dependent stuff
 103 #ifdef TARGET_OS_FAMILY_linux
 104 # include "osThread_linux.hpp"
 105 #endif
 106 #ifdef TARGET_OS_FAMILY_solaris
 107 # include "osThread_solaris.hpp"
 108 #endif
 109 #ifdef TARGET_OS_FAMILY_windows
 110 # include "osThread_windows.hpp"
 111 #endif
 112 #ifdef TARGET_OS_FAMILY_bsd
 113 # include "osThread_bsd.hpp"
 114 #endif
 115 
 116 };
 117 
 118 
 119 // Utility class for use with condition variables:
 120 class OSThreadWaitState : public StackObj {
 121   OSThread*   _osthread;
 122   ThreadState _old_state;
 123  public:
 124   OSThreadWaitState(OSThread* osthread, bool is_object_wait) {
 125     _osthread  = osthread;
 126     _old_state = osthread->get_state();
 127     if (is_object_wait) {
 128       osthread->set_state(OBJECT_WAIT);
 129     } else {
 130       osthread->set_state(CONDVAR_WAIT);
 131     }
 132   }
 133   ~OSThreadWaitState() {
 134     _osthread->set_state(_old_state);
 135   }
 136 };
 137 
 138 
 139 // Utility class for use with contended monitors:
 140 class OSThreadContendState : public StackObj {
 141   OSThread*   _osthread;
 142   ThreadState _old_state;
 143  public:
 144   OSThreadContendState(OSThread* osthread) {
 145     _osthread  = osthread;
 146     _old_state = osthread->get_state();
 147     osthread->set_state(MONITOR_WAIT);
 148   }
 149   ~OSThreadContendState() {
 150     _osthread->set_state(_old_state);
 151   }
 152 };
 153 
 154 #endif // SHARE_VM_RUNTIME_OSTHREAD_HPP