1 /*
   2  * Copyright (c) 1997, 2013, 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
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_RUNTIME_VM_OPERATIONS_HPP
  26 #define SHARE_VM_RUNTIME_VM_OPERATIONS_HPP
  27 
  28 #include "classfile/javaClasses.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "oops/oop.hpp"
  31 #include "runtime/thread.hpp"
  32 #include "utilities/top.hpp"
  33 
  34 // The following classes are used for operations
  35 // initiated by a Java thread but that must
  36 // take place in the VMThread.
  37 
  38 #define VM_OP_ENUM(type)   VMOp_##type,
  39 
  40 // Note: When new VM_XXX comes up, add 'XXX' to the template table.
  41 #define VM_OPS_DO(template)                       \
  42   template(Dummy)                                 \
  43   template(ThreadStop)                            \
  44   template(ThreadDump)                            \
  45   template(PrintThreads)                          \
  46   template(FindDeadlocks)                         \
  47   template(ForceSafepoint)                        \
  48   template(ForceAsyncSafepoint)                   \
  49   template(Deoptimize)                            \
  50   template(DeoptimizeFrame)                       \
  51   template(DeoptimizeAll)                         \
  52   template(ZombieAll)                             \
  53   template(UnlinkSymbols)                         \
  54   template(Verify)                                \
  55   template(PrintJNI)                              \
  56   template(HeapDumper)                            \
  57   template(DeoptimizeTheWorld)                    \
  58   template(CollectForMetadataAllocation)          \
  59   template(GC_HeapInspection)                     \
  60   template(GenCollectFull)                        \
  61   template(GenCollectFullConcurrent)              \
  62   template(GenCollectForAllocation)               \
  63   template(ParallelGCFailedAllocation)            \
  64   template(ParallelGCSystemGC)                    \
  65   template(CGC_Operation)                         \
  66   template(CMS_Initial_Mark)                      \
  67   template(CMS_Final_Remark)                      \
  68   template(G1CollectFull)                         \
  69   template(G1CollectForAllocation)                \
  70   template(G1IncCollectionPause)                  \
  71   template(EnableBiasedLocking)                   \
  72   template(RevokeBias)                            \
  73   template(BulkRevokeBias)                        \
  74   template(PopulateDumpSharedSpace)               \
  75   template(JNIFunctionTableCopier)                \
  76   template(RedefineClasses)                       \
  77   template(GetOwnedMonitorInfo)                   \
  78   template(GetObjectMonitorUsage)                 \
  79   template(GetCurrentContendedMonitor)            \
  80   template(GetStackTrace)                         \
  81   template(GetMultipleStackTraces)                \
  82   template(GetAllStackTraces)                     \
  83   template(GetThreadListStackTraces)              \
  84   template(GetFrameCount)                         \
  85   template(GetFrameLocation)                      \
  86   template(ChangeBreakpoints)                     \
  87   template(GetOrSetLocal)                         \
  88   template(GetCurrentLocation)                    \
  89   template(EnterInterpOnlyMode)                   \
  90   template(ChangeSingleStep)                      \
  91   template(HeapWalkOperation)                     \
  92   template(HeapIterateOperation)                  \
  93   template(ReportJavaOutOfMemory)                 \
  94   template(JFRCheckpoint)                         \
  95   template(Exit)                                  \
  96   template(LinuxDllLoad)                          \
  97 
  98 class VM_Operation: public CHeapObj<mtInternal> {
  99  public:
 100   enum Mode {
 101     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated
 102     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated
 103     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated
 104     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated
 105   };
 106 
 107   enum VMOp_Type {
 108     VM_OPS_DO(VM_OP_ENUM)
 109     VMOp_Terminating
 110   };
 111 
 112  private:
 113   Thread*         _calling_thread;
 114   ThreadPriority  _priority;
 115   long            _timestamp;
 116   VM_Operation*   _next;
 117   VM_Operation*   _prev;
 118 
 119   // The VM operation name array
 120   static const char* _names[];
 121 
 122  public:
 123   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }
 124   virtual ~VM_Operation() {}
 125 
 126   // VM operation support (used by VM thread)
 127   Thread* calling_thread() const                 { return _calling_thread; }
 128   ThreadPriority priority()                      { return _priority; }
 129   void set_calling_thread(Thread* thread, ThreadPriority priority);
 130 
 131   long timestamp() const              { return _timestamp; }
 132   void set_timestamp(long timestamp)  { _timestamp = timestamp; }
 133 
 134   // Called by VM thread - does in turn invoke doit(). Do not override this
 135   void evaluate();
 136 
 137   // evaluate() is called by the VMThread and in turn calls doit().
 138   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,
 139   // doit_prologue() is called in that thread before transferring control to
 140   // the VMThread.
 141   // If doit_prologue() returns true the VM operation will proceed, and
 142   // doit_epilogue() will be called by the JavaThread once the VM operation
 143   // completes. If doit_prologue() returns false the VM operation is cancelled.
 144   virtual void doit()                            = 0;
 145   virtual bool doit_prologue()                   { return true; };
 146   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent
 147 
 148   // Type test
 149   virtual bool is_methodCompiler() const         { return false; }
 150 
 151   // Linking
 152   VM_Operation *next() const                     { return _next; }
 153   VM_Operation *prev() const                     { return _prev; }
 154   void set_next(VM_Operation *next)              { _next = next; }
 155   void set_prev(VM_Operation *prev)              { _prev = prev; }
 156 
 157   // Configuration. Override these appropriately in subclasses.
 158   virtual VMOp_Type type() const = 0;
 159   virtual Mode evaluation_mode() const            { return _safepoint; }
 160   virtual bool allow_nested_vm_operations() const { return false; }
 161   virtual bool is_cheap_allocated() const         { return false; }
 162   virtual void oops_do(OopClosure* f)              { /* do nothing */ };
 163 
 164   // CAUTION: <don't hang yourself with following rope>
 165   // If you override these methods, make sure that the evaluation
 166   // of these methods is race-free and non-blocking, since these
 167   // methods may be evaluated either by the mutators or by the
 168   // vm thread, either concurrently with mutators or with the mutators
 169   // stopped. In other words, taking locks is verboten, and if there
 170   // are any races in evaluating the conditions, they'd better be benign.
 171   virtual bool evaluate_at_safepoint() const {
 172     return evaluation_mode() == _safepoint  ||
 173            evaluation_mode() == _async_safepoint;
 174   }
 175   virtual bool evaluate_concurrently() const {
 176     return evaluation_mode() == _concurrent ||
 177            evaluation_mode() == _async_safepoint;
 178   }
 179 
 180   static const char* mode_to_string(Mode mode);
 181 
 182   // Debugging
 183   void print_on_error(outputStream* st) const;
 184   const char* name() const { return _names[type()]; }
 185   static const char* name(int type) {
 186     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");
 187     return _names[type];
 188   }
 189 #ifndef PRODUCT
 190   void print_on(outputStream* st) const { print_on_error(st); }
 191 #endif
 192 };
 193 
 194 class VM_ThreadStop: public VM_Operation {
 195  private:
 196   oop     _thread;        // The Thread that the Throwable is thrown against
 197   oop     _throwable;     // The Throwable thrown at the target Thread
 198  public:
 199   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the
 200   // VM operation is executed.
 201   VM_ThreadStop(oop thread, oop throwable) {
 202     _thread    = thread;
 203     _throwable = throwable;
 204   }
 205   VMOp_Type type() const                         { return VMOp_ThreadStop; }
 206   oop target_thread() const                      { return _thread; }
 207   oop throwable() const                          { return _throwable;}
 208   void doit();
 209   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated
 210   bool allow_nested_vm_operations() const        { return true; }
 211   Mode evaluation_mode() const                   { return _async_safepoint; }
 212   bool is_cheap_allocated() const                { return true; }
 213 
 214   // GC support
 215   void oops_do(OopClosure* f) {
 216     f->do_oop(&_thread); f->do_oop(&_throwable);
 217   }
 218 };
 219 
 220 // dummy vm op, evaluated just to force a safepoint
 221 class VM_ForceSafepoint: public VM_Operation {
 222  public:
 223   VM_ForceSafepoint() {}
 224   void doit()         {}
 225   VMOp_Type type() const { return VMOp_ForceSafepoint; }
 226 };
 227 
 228 // dummy vm op, evaluated just to force a safepoint
 229 class VM_ForceAsyncSafepoint: public VM_Operation {
 230  public:
 231   VM_ForceAsyncSafepoint() {}
 232   void doit()              {}
 233   VMOp_Type type() const                         { return VMOp_ForceAsyncSafepoint; }
 234   Mode evaluation_mode() const                   { return _async_safepoint; }
 235   bool is_cheap_allocated() const                { return true; }
 236 };
 237 
 238 class VM_Deoptimize: public VM_Operation {
 239  public:
 240   VM_Deoptimize() {}
 241   VMOp_Type type() const                        { return VMOp_Deoptimize; }
 242   void doit();
 243   bool allow_nested_vm_operations() const        { return true; }
 244 };
 245 
 246 
 247 // Deopt helper that can deoptimize frames in threads other than the
 248 // current thread.  Only used through Deoptimization::deoptimize_frame.
 249 class VM_DeoptimizeFrame: public VM_Operation {
 250   friend class Deoptimization;
 251 
 252  private:
 253   JavaThread* _thread;
 254   intptr_t*   _id;
 255   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id);
 256 
 257  public:
 258   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }
 259   void doit();
 260   bool allow_nested_vm_operations() const        { return true;  }
 261 };
 262 
 263 #ifndef PRODUCT
 264 class VM_DeoptimizeAll: public VM_Operation {
 265  private:
 266   KlassHandle _dependee;
 267  public:
 268   VM_DeoptimizeAll() {}
 269   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }
 270   void doit();
 271   bool allow_nested_vm_operations() const        { return true; }
 272 };
 273 
 274 
 275 class VM_ZombieAll: public VM_Operation {
 276  public:
 277   VM_ZombieAll() {}
 278   VMOp_Type type() const                         { return VMOp_ZombieAll; }
 279   void doit();
 280   bool allow_nested_vm_operations() const        { return true; }
 281 };
 282 #endif // PRODUCT
 283 
 284 class VM_UnlinkSymbols: public VM_Operation {
 285  public:
 286   VM_UnlinkSymbols() {}
 287   VMOp_Type type() const                         { return VMOp_UnlinkSymbols; }
 288   void doit();
 289   bool allow_nested_vm_operations() const        { return true; }
 290 };
 291 
 292 class VM_Verify: public VM_Operation {
 293  private:
 294   bool _silent;
 295  public:
 296   VM_Verify(bool silent = VerifySilently) : _silent(silent) {}
 297   VMOp_Type type() const { return VMOp_Verify; }
 298   void doit();
 299 };
 300 
 301 
 302 class VM_PrintThreads: public VM_Operation {
 303  private:
 304   outputStream* _out;
 305   bool _print_concurrent_locks;
 306  public:
 307   VM_PrintThreads()                                                { _out = tty; _print_concurrent_locks = PrintConcurrentLocks; }
 308   VM_PrintThreads(outputStream* out, bool print_concurrent_locks)  { _out = out; _print_concurrent_locks = print_concurrent_locks; }
 309   VMOp_Type type() const                                           {  return VMOp_PrintThreads; }
 310   void doit();
 311   bool doit_prologue();
 312   void doit_epilogue();
 313 };
 314 
 315 class VM_PrintJNI: public VM_Operation {
 316  private:
 317   outputStream* _out;
 318  public:
 319   VM_PrintJNI()                         { _out = tty; }
 320   VM_PrintJNI(outputStream* out)        { _out = out; }
 321   VMOp_Type type() const                { return VMOp_PrintJNI; }
 322   void doit();
 323 };
 324 
 325 class DeadlockCycle;
 326 class VM_FindDeadlocks: public VM_Operation {
 327  private:
 328   bool           _concurrent_locks;
 329   DeadlockCycle* _deadlocks;
 330   outputStream*  _out;
 331 
 332  public:
 333   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _out(NULL), _deadlocks(NULL) {};
 334   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _out(st), _deadlocks(NULL) {};
 335   ~VM_FindDeadlocks();
 336 
 337   DeadlockCycle* result()      { return _deadlocks; };
 338   VMOp_Type type() const       { return VMOp_FindDeadlocks; }
 339   void doit();
 340   bool doit_prologue();
 341 };
 342 
 343 class ThreadDumpResult;
 344 class ThreadSnapshot;
 345 class ThreadConcurrentLocks;
 346 
 347 class VM_ThreadDump : public VM_Operation {
 348  private:
 349   ThreadDumpResult*              _result;
 350   int                            _num_threads;
 351   GrowableArray<instanceHandle>* _threads;
 352   int                            _max_depth;
 353   bool                           _with_locked_monitors;
 354   bool                           _with_locked_synchronizers;
 355 
 356   ThreadSnapshot* snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl);
 357 
 358  public:
 359   VM_ThreadDump(ThreadDumpResult* result,
 360                 int max_depth,  // -1 indicates entire stack
 361                 bool with_locked_monitors,
 362                 bool with_locked_synchronizers);
 363 
 364   VM_ThreadDump(ThreadDumpResult* result,
 365                 GrowableArray<instanceHandle>* threads,
 366                 int num_threads, // -1 indicates entire stack
 367                 int max_depth,
 368                 bool with_locked_monitors,
 369                 bool with_locked_synchronizers);
 370 
 371   VMOp_Type type() const { return VMOp_ThreadDump; }
 372   void doit();
 373   bool doit_prologue();
 374   void doit_epilogue();
 375 };
 376 
 377 
 378 class VM_Exit: public VM_Operation {
 379  private:
 380   int  _exit_code;
 381   static volatile bool _vm_exited;
 382   static Thread * _shutdown_thread;
 383   static void wait_if_vm_exited();
 384  public:
 385   VM_Exit(int exit_code) {
 386     _exit_code = exit_code;
 387   }
 388   static int wait_for_threads_in_native_to_block();
 389   static int set_vm_exited();
 390   static bool vm_exited()                      { return _vm_exited; }
 391   static void block_if_vm_exited() {
 392     if (_vm_exited) {
 393       wait_if_vm_exited();
 394     }
 395   }
 396   VMOp_Type type() const { return VMOp_Exit; }
 397   void doit();
 398 };
 399 
 400 #endif // SHARE_VM_RUNTIME_VM_OPERATIONS_HPP