1 /*
   2  * Copyright (c) 1997, 2017, 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 "runtime/threadSMR.hpp"
  33 #include "code/codeCache.hpp"
  34 
  35 // The following classes are used for operations
  36 // initiated by a Java thread but that must
  37 // take place in the VMThread.
  38 
  39 #define VM_OP_ENUM(type)   VMOp_##type,
  40 
  41 // Note: When new VM_XXX comes up, add 'XXX' to the template table.
  42 #define VM_OPS_DO(template)                       \
  43   template(Dummy)                                 \
  44   template(ThreadStop)                            \
  45   template(ThreadDump)                            \
  46   template(PrintThreads)                          \
  47   template(FindDeadlocks)                         \
  48   template(ClearICs)                              \
  49   template(ForceSafepoint)                        \
  50   template(ForceAsyncSafepoint)                   \
  51   template(Deoptimize)                            \
  52   template(DeoptimizeFrame)                       \
  53   template(DeoptimizeAll)                         \
  54   template(ZombieAll)                             \
  55   template(UnlinkSymbols)                         \
  56   template(Verify)                                \
  57   template(PrintJNI)                              \
  58   template(HeapDumper)                            \
  59   template(DeoptimizeTheWorld)                    \
  60   template(CollectForMetadataAllocation)          \
  61   template(GC_HeapInspection)                     \
  62   template(GenCollectFull)                        \
  63   template(GenCollectFullConcurrent)              \
  64   template(GenCollectForAllocation)               \
  65   template(ParallelGCFailedAllocation)            \
  66   template(ParallelGCSystemGC)                    \
  67   template(CGC_Operation)                         \
  68   template(CMS_Initial_Mark)                      \
  69   template(CMS_Final_Remark)                      \
  70   template(G1CollectFull)                         \
  71   template(G1CollectForAllocation)                \
  72   template(G1IncCollectionPause)                  \
  73   template(HandshakeOneThread)                    \
  74   template(HandshakeAllThreads)                   \
  75   template(HandshakeFallback)                     \
  76   template(DestroyAllocationContext)              \
  77   template(EnableBiasedLocking)                   \
  78   template(RevokeBias)                            \
  79   template(BulkRevokeBias)                        \
  80   template(PopulateDumpSharedSpace)               \
  81   template(JNIFunctionTableCopier)                \
  82   template(RedefineClasses)                       \
  83   template(UpdateForPopTopFrame)                  \
  84   template(SetFramePop)                           \
  85   template(GetOwnedMonitorInfo)                   \
  86   template(GetObjectMonitorUsage)                 \
  87   template(GetCurrentContendedMonitor)            \
  88   template(GetStackTrace)                         \
  89   template(GetMultipleStackTraces)                \
  90   template(GetAllStackTraces)                     \
  91   template(GetThreadListStackTraces)              \
  92   template(GetFrameCount)                         \
  93   template(GetFrameLocation)                      \
  94   template(ChangeBreakpoints)                     \
  95   template(GetOrSetLocal)                         \
  96   template(GetCurrentLocation)                    \
  97   template(EnterInterpOnlyMode)                   \
  98   template(ChangeSingleStep)                      \
  99   template(HeapWalkOperation)                     \
 100   template(HeapIterateOperation)                  \
 101   template(ReportJavaOutOfMemory)                 \
 102   template(JFRCheckpoint)                         \
 103   template(Exit)                                  \
 104   template(LinuxDllLoad)                          \
 105   template(RotateGCLog)                           \
 106   template(WhiteBoxOperation)                     \
 107   template(ClassLoaderStatsOperation)             \
 108   template(DumpHashtable)                         \
 109   template(DumpTouchedMethods)                    \
 110   template(MarkActiveNMethods)                    \
 111   template(PrintCompileQueue)                     \
 112   template(PrintClassHierarchy)                   \
 113   template(ThreadSuspend)                         \
 114   template(CTWThreshold)                          \
 115   template(ThreadsSuspendJVMTI)                   \
 116   template(ICBufferFull)                          \
 117   template(ScavengeMonitors)                      \
 118   template(PrintMetadata)                         \
 119 
 120 class VM_Operation: public CHeapObj<mtInternal> {
 121  public:
 122   enum Mode {
 123     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated
 124     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated
 125     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated
 126     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated
 127   };
 128 
 129   enum VMOp_Type {
 130     VM_OPS_DO(VM_OP_ENUM)
 131     VMOp_Terminating
 132   };
 133 
 134  private:
 135   Thread*         _calling_thread;
 136   ThreadPriority  _priority;
 137   long            _timestamp;
 138   VM_Operation*   _next;
 139   VM_Operation*   _prev;
 140 
 141   // The VM operation name array
 142   static const char* _names[];
 143 
 144  public:
 145   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }
 146   virtual ~VM_Operation() {}
 147 
 148   // VM operation support (used by VM thread)
 149   Thread* calling_thread() const                 { return _calling_thread; }
 150   ThreadPriority priority()                      { return _priority; }
 151   void set_calling_thread(Thread* thread, ThreadPriority priority);
 152 
 153   long timestamp() const              { return _timestamp; }
 154   void set_timestamp(long timestamp)  { _timestamp = timestamp; }
 155 
 156   // Called by VM thread - does in turn invoke doit(). Do not override this
 157   void evaluate();
 158 
 159   // evaluate() is called by the VMThread and in turn calls doit().
 160   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,
 161   // doit_prologue() is called in that thread before transferring control to
 162   // the VMThread.
 163   // If doit_prologue() returns true the VM operation will proceed, and
 164   // doit_epilogue() will be called by the JavaThread once the VM operation
 165   // completes. If doit_prologue() returns false the VM operation is cancelled.
 166   virtual void doit()                            = 0;
 167   virtual bool doit_prologue()                   { return true; };
 168   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent
 169 
 170   // Type test
 171   virtual bool is_methodCompiler() const         { return false; }
 172 
 173   // Linking
 174   VM_Operation *next() const                     { return _next; }
 175   VM_Operation *prev() const                     { return _prev; }
 176   void set_next(VM_Operation *next)              { _next = next; }
 177   void set_prev(VM_Operation *prev)              { _prev = prev; }
 178 
 179   // Configuration. Override these appropriately in subclasses.
 180   virtual VMOp_Type type() const = 0;
 181   virtual Mode evaluation_mode() const            { return _safepoint; }
 182   virtual bool allow_nested_vm_operations() const { return false; }
 183   virtual bool is_cheap_allocated() const         { return false; }
 184   virtual void oops_do(OopClosure* f)              { /* do nothing */ };
 185 
 186   // CAUTION: <don't hang yourself with following rope>
 187   // If you override these methods, make sure that the evaluation
 188   // of these methods is race-free and non-blocking, since these
 189   // methods may be evaluated either by the mutators or by the
 190   // vm thread, either concurrently with mutators or with the mutators
 191   // stopped. In other words, taking locks is verboten, and if there
 192   // are any races in evaluating the conditions, they'd better be benign.
 193   virtual bool evaluate_at_safepoint() const {
 194     return evaluation_mode() == _safepoint  ||
 195            evaluation_mode() == _async_safepoint;
 196   }
 197   virtual bool evaluate_concurrently() const {
 198     return evaluation_mode() == _concurrent ||
 199            evaluation_mode() == _async_safepoint;
 200   }
 201 
 202   static const char* mode_to_string(Mode mode);
 203 
 204   // Debugging
 205   virtual void print_on_error(outputStream* st) const;
 206   const char* name() const { return _names[type()]; }
 207   static const char* name(int type) {
 208     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");
 209     return _names[type];
 210   }
 211 #ifndef PRODUCT
 212   void print_on(outputStream* st) const { print_on_error(st); }
 213 #endif
 214 };
 215 
 216 class VM_ThreadStop: public VM_Operation {
 217  private:
 218   oop     _thread;        // The Thread that the Throwable is thrown against
 219   oop     _throwable;     // The Throwable thrown at the target Thread
 220  public:
 221   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the
 222   // VM operation is executed.
 223   VM_ThreadStop(oop thread, oop throwable) {
 224     _thread    = thread;
 225     _throwable = throwable;
 226   }
 227   VMOp_Type type() const                         { return VMOp_ThreadStop; }
 228   oop target_thread() const                      { return _thread; }
 229   oop throwable() const                          { return _throwable;}
 230   void doit();
 231   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated
 232   bool allow_nested_vm_operations() const        { return true; }
 233   Mode evaluation_mode() const                   { return _async_safepoint; }
 234   bool is_cheap_allocated() const                { return true; }
 235 
 236   // GC support
 237   void oops_do(OopClosure* f) {
 238     f->do_oop(&_thread); f->do_oop(&_throwable);
 239   }
 240 };
 241 
 242 class VM_ClearICs: public VM_Operation {
 243  private:
 244   bool _preserve_static_stubs;
 245  public:
 246   VM_ClearICs(bool preserve_static_stubs) { _preserve_static_stubs = preserve_static_stubs; }
 247   void doit();
 248   VMOp_Type type() const { return VMOp_ClearICs; }
 249 };
 250 
 251 // empty vm op, evaluated just to force a safepoint
 252 class VM_ForceSafepoint: public VM_Operation {
 253  public:
 254   void doit()         {}
 255   VMOp_Type type() const { return VMOp_ForceSafepoint; }
 256 };
 257 
 258 // empty vm op, when forcing a safepoint to suspend a thread
 259 class VM_ThreadSuspend: public VM_ForceSafepoint {
 260  public:
 261   VMOp_Type type() const { return VMOp_ThreadSuspend; }
 262 };
 263 
 264 // empty vm op, when forcing a safepoint due to ctw threshold is reached for the sweeper
 265 class VM_CTWThreshold: public VM_ForceSafepoint {
 266  public:
 267   VMOp_Type type() const { return VMOp_CTWThreshold; }
 268 };
 269 
 270 // empty vm op, when forcing a safepoint to suspend threads from jvmti
 271 class VM_ThreadsSuspendJVMTI: public VM_ForceSafepoint {
 272  public:
 273   VMOp_Type type() const { return VMOp_ThreadsSuspendJVMTI; }
 274 };
 275 
 276 // empty vm op, when forcing a safepoint due to inline cache buffers being full
 277 class VM_ICBufferFull: public VM_ForceSafepoint {
 278  public:
 279   VMOp_Type type() const { return VMOp_ICBufferFull; }
 280 };
 281 
 282 // empty asynchronous vm op, when forcing a safepoint to scavenge monitors
 283 class VM_ScavengeMonitors: public VM_ForceSafepoint {
 284  public:
 285   VMOp_Type type() const                         { return VMOp_ScavengeMonitors; }
 286   Mode evaluation_mode() const                   { return _async_safepoint; }
 287   bool is_cheap_allocated() const                { return true; }
 288 };
 289 
 290 class VM_Deoptimize: public VM_Operation {
 291  public:
 292   VM_Deoptimize() {}
 293   VMOp_Type type() const                        { return VMOp_Deoptimize; }
 294   void doit();
 295   bool allow_nested_vm_operations() const        { return true; }
 296 };
 297 
 298 class VM_MarkActiveNMethods: public VM_Operation {
 299  public:
 300   VM_MarkActiveNMethods() {}
 301   VMOp_Type type() const                         { return VMOp_MarkActiveNMethods; }
 302   void doit();
 303   bool allow_nested_vm_operations() const        { return true; }
 304 };
 305 
 306 // Deopt helper that can deoptimize frames in threads other than the
 307 // current thread.  Only used through Deoptimization::deoptimize_frame.
 308 class VM_DeoptimizeFrame: public VM_Operation {
 309   friend class Deoptimization;
 310 
 311  private:
 312   JavaThread* _thread;
 313   intptr_t*   _id;
 314   int _reason;
 315   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id, int reason);
 316 
 317  public:
 318   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }
 319   void doit();
 320   bool allow_nested_vm_operations() const        { return true;  }
 321 };
 322 
 323 #ifndef PRODUCT
 324 class VM_DeoptimizeAll: public VM_Operation {
 325  private:
 326   Klass* _dependee;
 327  public:
 328   VM_DeoptimizeAll() {}
 329   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }
 330   void doit();
 331   bool allow_nested_vm_operations() const        { return true; }
 332 };
 333 
 334 
 335 class VM_ZombieAll: public VM_Operation {
 336  public:
 337   VM_ZombieAll() {}
 338   VMOp_Type type() const                         { return VMOp_ZombieAll; }
 339   void doit();
 340   bool allow_nested_vm_operations() const        { return true; }
 341 };
 342 #endif // PRODUCT
 343 
 344 class VM_UnlinkSymbols: public VM_Operation {
 345  public:
 346   VM_UnlinkSymbols() {}
 347   VMOp_Type type() const                         { return VMOp_UnlinkSymbols; }
 348   void doit();
 349   bool allow_nested_vm_operations() const        { return true; }
 350 };
 351 
 352 class VM_Verify: public VM_Operation {
 353  public:
 354   VMOp_Type type() const { return VMOp_Verify; }
 355   void doit();
 356 };
 357 
 358 
 359 class VM_PrintThreads: public VM_Operation {
 360  private:
 361   outputStream* _out;
 362   bool _print_concurrent_locks;
 363  public:
 364   VM_PrintThreads()                                                { _out = tty; _print_concurrent_locks = PrintConcurrentLocks; }
 365   VM_PrintThreads(outputStream* out, bool print_concurrent_locks)  { _out = out; _print_concurrent_locks = print_concurrent_locks; }
 366   VMOp_Type type() const                                           {  return VMOp_PrintThreads; }
 367   void doit();
 368   bool doit_prologue();
 369   void doit_epilogue();
 370 };
 371 
 372 class VM_PrintJNI: public VM_Operation {
 373  private:
 374   outputStream* _out;
 375  public:
 376   VM_PrintJNI()                         { _out = tty; }
 377   VM_PrintJNI(outputStream* out)        { _out = out; }
 378   VMOp_Type type() const                { return VMOp_PrintJNI; }
 379   void doit();
 380 };
 381 
 382 class VM_PrintMetadata : public VM_Operation {
 383  private:
 384   outputStream* _out;
 385   size_t        _scale;
 386  public:
 387   VM_PrintMetadata(outputStream* out, size_t scale) : _out(out), _scale(scale) {};
 388 
 389   VMOp_Type type() const  { return VMOp_PrintMetadata; }
 390   void doit();
 391 };
 392 
 393 class DeadlockCycle;
 394 class VM_FindDeadlocks: public VM_Operation {
 395  private:
 396   bool              _concurrent_locks;
 397   DeadlockCycle*    _deadlocks;
 398   outputStream*     _out;
 399   ThreadsListSetter _setter;  // Helper to set hazard ptr in the originating thread
 400                               // which protects the JavaThreads in _deadlocks.
 401 
 402  public:
 403   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _out(NULL), _deadlocks(NULL), _setter() {};
 404   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _out(st), _deadlocks(NULL) {};
 405   ~VM_FindDeadlocks();
 406 
 407   DeadlockCycle* result()      { return _deadlocks; };
 408   VMOp_Type type() const       { return VMOp_FindDeadlocks; }
 409   void doit();
 410   bool doit_prologue();
 411 };
 412 
 413 class ThreadDumpResult;
 414 class ThreadSnapshot;
 415 class ThreadConcurrentLocks;
 416 
 417 class VM_ThreadDump : public VM_Operation {
 418  private:
 419   ThreadDumpResult*              _result;
 420   int                            _num_threads;
 421   GrowableArray<instanceHandle>* _threads;
 422   int                            _max_depth;
 423   bool                           _with_locked_monitors;
 424   bool                           _with_locked_synchronizers;
 425 
 426   ThreadSnapshot* snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl);
 427 
 428  public:
 429   VM_ThreadDump(ThreadDumpResult* result,
 430                 int max_depth,  // -1 indicates entire stack
 431                 bool with_locked_monitors,
 432                 bool with_locked_synchronizers);
 433 
 434   VM_ThreadDump(ThreadDumpResult* result,
 435                 GrowableArray<instanceHandle>* threads,
 436                 int num_threads, // -1 indicates entire stack
 437                 int max_depth,
 438                 bool with_locked_monitors,
 439                 bool with_locked_synchronizers);
 440 
 441   VMOp_Type type() const { return VMOp_ThreadDump; }
 442   void doit();
 443   bool doit_prologue();
 444   void doit_epilogue();
 445 };
 446 
 447 
 448 class VM_Exit: public VM_Operation {
 449  private:
 450   int  _exit_code;
 451   static volatile bool _vm_exited;
 452   static Thread * _shutdown_thread;
 453   static void wait_if_vm_exited();
 454  public:
 455   VM_Exit(int exit_code) {
 456     _exit_code = exit_code;
 457   }
 458   static int wait_for_threads_in_native_to_block();
 459   static int set_vm_exited();
 460   static bool vm_exited()                      { return _vm_exited; }
 461   static void block_if_vm_exited() {
 462     if (_vm_exited) {
 463       wait_if_vm_exited();
 464     }
 465   }
 466   VMOp_Type type() const { return VMOp_Exit; }
 467   void doit();
 468 };
 469 
 470 class VM_PrintCompileQueue: public VM_Operation {
 471  private:
 472   outputStream* _out;
 473 
 474  public:
 475   VM_PrintCompileQueue(outputStream* st) : _out(st) {}
 476   VMOp_Type type() const { return VMOp_PrintCompileQueue; }
 477   Mode evaluation_mode() const { return _safepoint; }
 478   void doit();
 479 };
 480 
 481 #if INCLUDE_SERVICES
 482 class VM_PrintClassHierarchy: public VM_Operation {
 483  private:
 484   outputStream* _out;
 485   bool _print_interfaces;
 486   bool _print_subclasses;
 487   char* _classname;
 488 
 489  public:
 490   VM_PrintClassHierarchy(outputStream* st, bool print_interfaces, bool print_subclasses, char* classname) :
 491     _out(st), _print_interfaces(print_interfaces), _print_subclasses(print_subclasses),
 492     _classname(classname) {}
 493   VMOp_Type type() const { return VMOp_PrintClassHierarchy; }
 494   void doit();
 495 };
 496 #endif // INCLUDE_SERVICES
 497 
 498 #endif // SHARE_VM_RUNTIME_VM_OPERATIONS_HPP