1 /*
   2  * Copyright (c) 1997, 2018, 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(G1CollectForAllocation)                \
  71   template(G1CollectFull)                         \
  72   template(ZOperation)                            \
  73   template(HandshakeOneThread)                    \
  74   template(HandshakeAllThreads)                   \
  75   template(HandshakeFallback)                     \
  76   template(EnableBiasedLocking)                   \
  77   template(RevokeBias)                            \
  78   template(BulkRevokeBias)                        \
  79   template(PopulateDumpSharedSpace)               \
  80   template(JNIFunctionTableCopier)                \
  81   template(RedefineClasses)                       \
  82   template(UpdateForPopTopFrame)                  \
  83   template(SetFramePop)                           \
  84   template(GetOwnedMonitorInfo)                   \
  85   template(GetObjectMonitorUsage)                 \
  86   template(GetCurrentContendedMonitor)            \
  87   template(GetStackTrace)                         \
  88   template(GetMultipleStackTraces)                \
  89   template(GetAllStackTraces)                     \
  90   template(GetThreadListStackTraces)              \
  91   template(GetFrameCount)                         \
  92   template(GetFrameLocation)                      \
  93   template(ChangeBreakpoints)                     \
  94   template(GetOrSetLocal)                         \
  95   template(GetCurrentLocation)                    \
  96   template(EnterInterpOnlyMode)                   \
  97   template(ChangeSingleStep)                      \
  98   template(HeapWalkOperation)                     \
  99   template(HeapIterateOperation)                  \
 100   template(ReportJavaOutOfMemory)                 \
 101   template(JFRCheckpoint)                         \
 102   template(Exit)                                  \
 103   template(LinuxDllLoad)                          \
 104   template(RotateGCLog)                           \
 105   template(WhiteBoxOperation)                     \
 106   template(ClassLoaderStatsOperation)             \
 107   template(ClassLoaderHierarchyOperation)         \
 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   template(GTestExecuteAtSafepoint)               \
 120   template(JFROldObject)                          \
 121 
 122 class VM_Operation: public CHeapObj<mtInternal> {
 123  public:
 124   enum Mode {
 125     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated
 126     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated
 127     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated
 128     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated
 129   };
 130 
 131   enum VMOp_Type {
 132     VM_OPS_DO(VM_OP_ENUM)
 133     VMOp_Terminating
 134   };
 135 
 136  private:
 137   Thread*         _calling_thread;
 138   ThreadPriority  _priority;
 139   long            _timestamp;
 140   VM_Operation*   _next;
 141   VM_Operation*   _prev;
 142 
 143   // The VM operation name array
 144   static const char* _names[];
 145 
 146  public:
 147   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }
 148   virtual ~VM_Operation() {}
 149 
 150   // VM operation support (used by VM thread)
 151   Thread* calling_thread() const                 { return _calling_thread; }
 152   ThreadPriority priority()                      { return _priority; }
 153   void set_calling_thread(Thread* thread, ThreadPriority priority);
 154 
 155   long timestamp() const              { return _timestamp; }
 156   void set_timestamp(long timestamp)  { _timestamp = timestamp; }
 157 
 158   // Called by VM thread - does in turn invoke doit(). Do not override this
 159   void evaluate();
 160 
 161   // evaluate() is called by the VMThread and in turn calls doit().
 162   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,
 163   // doit_prologue() is called in that thread before transferring control to
 164   // the VMThread.
 165   // If doit_prologue() returns true the VM operation will proceed, and
 166   // doit_epilogue() will be called by the JavaThread once the VM operation
 167   // completes. If doit_prologue() returns false the VM operation is cancelled.
 168   virtual void doit()                            = 0;
 169   virtual bool doit_prologue()                   { return true; };
 170   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent
 171 
 172   // Type test
 173   virtual bool is_methodCompiler() const         { return false; }
 174 
 175   // Linking
 176   VM_Operation *next() const                     { return _next; }
 177   VM_Operation *prev() const                     { return _prev; }
 178   void set_next(VM_Operation *next)              { _next = next; }
 179   void set_prev(VM_Operation *prev)              { _prev = prev; }
 180 
 181   // Configuration. Override these appropriately in subclasses.
 182   virtual VMOp_Type type() const = 0;
 183   virtual Mode evaluation_mode() const            { return _safepoint; }
 184   virtual bool allow_nested_vm_operations() const { return false; }
 185   virtual bool is_cheap_allocated() const         { return false; }
 186   virtual void oops_do(OopClosure* f)              { /* do nothing */ };
 187 
 188   // CAUTION: <don't hang yourself with following rope>
 189   // If you override these methods, make sure that the evaluation
 190   // of these methods is race-free and non-blocking, since these
 191   // methods may be evaluated either by the mutators or by the
 192   // vm thread, either concurrently with mutators or with the mutators
 193   // stopped. In other words, taking locks is verboten, and if there
 194   // are any races in evaluating the conditions, they'd better be benign.
 195   virtual bool evaluate_at_safepoint() const {
 196     return evaluation_mode() == _safepoint  ||
 197            evaluation_mode() == _async_safepoint;
 198   }
 199   virtual bool evaluate_concurrently() const {
 200     return evaluation_mode() == _concurrent ||
 201            evaluation_mode() == _async_safepoint;
 202   }
 203 
 204   static const char* mode_to_string(Mode mode);
 205 
 206   // Debugging
 207   virtual void print_on_error(outputStream* st) const;
 208   const char* name() const { return _names[type()]; }
 209   static const char* name(int type) {
 210     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");
 211     return _names[type];
 212   }
 213 #ifndef PRODUCT
 214   void print_on(outputStream* st) const { print_on_error(st); }
 215 #endif
 216 };
 217 
 218 class VM_ThreadStop: public VM_Operation {
 219  private:
 220   oop     _thread;        // The Thread that the Throwable is thrown against
 221   oop     _throwable;     // The Throwable thrown at the target Thread
 222  public:
 223   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the
 224   // VM operation is executed.
 225   VM_ThreadStop(oop thread, oop throwable) {
 226     _thread    = thread;
 227     _throwable = throwable;
 228   }
 229   VMOp_Type type() const                         { return VMOp_ThreadStop; }
 230   oop target_thread() const                      { return _thread; }
 231   oop throwable() const                          { return _throwable;}
 232   void doit();
 233   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated
 234   bool allow_nested_vm_operations() const        { return true; }
 235   Mode evaluation_mode() const                   { return _async_safepoint; }
 236   bool is_cheap_allocated() const                { return true; }
 237 
 238   // GC support
 239   void oops_do(OopClosure* f) {
 240     f->do_oop(&_thread); f->do_oop(&_throwable);
 241   }
 242 };
 243 
 244 class VM_ClearICs: public VM_Operation {
 245  private:
 246   bool _preserve_static_stubs;
 247  public:
 248   VM_ClearICs(bool preserve_static_stubs) { _preserve_static_stubs = preserve_static_stubs; }
 249   void doit();
 250   VMOp_Type type() const { return VMOp_ClearICs; }
 251 };
 252 
 253 // empty vm op, evaluated just to force a safepoint
 254 class VM_ForceSafepoint: public VM_Operation {
 255  public:
 256   void doit()         {}
 257   VMOp_Type type() const { return VMOp_ForceSafepoint; }
 258 };
 259 
 260 // empty vm op, when forcing a safepoint to suspend a thread
 261 class VM_ThreadSuspend: public VM_ForceSafepoint {
 262  public:
 263   VMOp_Type type() const { return VMOp_ThreadSuspend; }
 264 };
 265 
 266 // empty vm op, when forcing a safepoint due to ctw threshold is reached for the sweeper
 267 class VM_CTWThreshold: public VM_ForceSafepoint {
 268  public:
 269   VMOp_Type type() const { return VMOp_CTWThreshold; }
 270 };
 271 
 272 // empty vm op, when forcing a safepoint to suspend threads from jvmti
 273 class VM_ThreadsSuspendJVMTI: public VM_ForceSafepoint {
 274  public:
 275   VMOp_Type type() const { return VMOp_ThreadsSuspendJVMTI; }
 276 };
 277 
 278 // empty vm op, when forcing a safepoint due to inline cache buffers being full
 279 class VM_ICBufferFull: public VM_ForceSafepoint {
 280  public:
 281   VMOp_Type type() const { return VMOp_ICBufferFull; }
 282 };
 283 
 284 // empty asynchronous vm op, when forcing a safepoint to scavenge monitors
 285 class VM_ScavengeMonitors: public VM_ForceSafepoint {
 286  public:
 287   VMOp_Type type() const                         { return VMOp_ScavengeMonitors; }
 288   Mode evaluation_mode() const                   { return _async_safepoint; }
 289   bool is_cheap_allocated() const                { return true; }
 290 };
 291 
 292 // Base class for invoking parts of a gtest in a safepoint.
 293 // Derived classes provide the doit method.
 294 // Typically also need to transition the gtest thread from native to VM.
 295 class VM_GTestExecuteAtSafepoint: public VM_Operation {
 296  public:
 297   VMOp_Type type() const                         { return VMOp_GTestExecuteAtSafepoint; }
 298 
 299  protected:
 300   VM_GTestExecuteAtSafepoint() {}
 301 };
 302 
 303 class VM_Deoptimize: public VM_Operation {
 304  public:
 305   VM_Deoptimize() {}
 306   VMOp_Type type() const                        { return VMOp_Deoptimize; }
 307   void doit();
 308   bool allow_nested_vm_operations() const        { return true; }
 309 };
 310 
 311 class VM_MarkActiveNMethods: public VM_Operation {
 312  public:
 313   VM_MarkActiveNMethods() {}
 314   VMOp_Type type() const                         { return VMOp_MarkActiveNMethods; }
 315   void doit();
 316   bool allow_nested_vm_operations() const        { return true; }
 317 };
 318 
 319 // Deopt helper that can deoptimize frames in threads other than the
 320 // current thread.  Only used through Deoptimization::deoptimize_frame.
 321 class VM_DeoptimizeFrame: public VM_Operation {
 322   friend class Deoptimization;
 323 
 324  private:
 325   JavaThread* _thread;
 326   intptr_t*   _id;
 327   int _reason;
 328   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id, int reason);
 329 
 330  public:
 331   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }
 332   void doit();
 333   bool allow_nested_vm_operations() const        { return true;  }
 334 };
 335 
 336 #ifndef PRODUCT
 337 class VM_DeoptimizeAll: public VM_Operation {
 338  private:
 339   Klass* _dependee;
 340  public:
 341   VM_DeoptimizeAll() {}
 342   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }
 343   void doit();
 344   bool allow_nested_vm_operations() const        { return true; }
 345 };
 346 
 347 
 348 class VM_ZombieAll: public VM_Operation {
 349  public:
 350   VM_ZombieAll() {}
 351   VMOp_Type type() const                         { return VMOp_ZombieAll; }
 352   void doit();
 353   bool allow_nested_vm_operations() const        { return true; }
 354 };
 355 #endif // PRODUCT
 356 
 357 class VM_UnlinkSymbols: public VM_Operation {
 358  public:
 359   VM_UnlinkSymbols() {}
 360   VMOp_Type type() const                         { return VMOp_UnlinkSymbols; }
 361   void doit();
 362   bool allow_nested_vm_operations() const        { return true; }
 363 };
 364 
 365 class VM_Verify: public VM_Operation {
 366  public:
 367   VMOp_Type type() const { return VMOp_Verify; }
 368   void doit();
 369 };
 370 
 371 
 372 class VM_PrintThreads: public VM_Operation {
 373  private:
 374   outputStream* _out;
 375   bool _print_concurrent_locks;
 376   bool _print_extended_info;
 377  public:
 378   VM_PrintThreads()
 379     : _out(tty), _print_concurrent_locks(PrintConcurrentLocks), _print_extended_info(false)
 380   {}
 381   VM_PrintThreads(outputStream* out, bool print_concurrent_locks, bool print_extended_info)
 382     : _out(out), _print_concurrent_locks(print_concurrent_locks), _print_extended_info(print_extended_info)
 383   {}
 384   VMOp_Type type() const {
 385     return VMOp_PrintThreads;
 386   }
 387   void doit();
 388   bool doit_prologue();
 389   void doit_epilogue();
 390 };
 391 
 392 class VM_PrintJNI: public VM_Operation {
 393  private:
 394   outputStream* _out;
 395  public:
 396   VM_PrintJNI()                         { _out = tty; }
 397   VM_PrintJNI(outputStream* out)        { _out = out; }
 398   VMOp_Type type() const                { return VMOp_PrintJNI; }
 399   void doit();
 400 };
 401 
 402 class VM_PrintMetadata : public VM_Operation {
 403  private:
 404   outputStream* const _out;
 405   const size_t        _scale;
 406   const int           _flags;
 407 
 408  public:
 409   VM_PrintMetadata(outputStream* out, size_t scale, int flags)
 410     : _out(out), _scale(scale), _flags(flags)
 411   {};
 412 
 413   VMOp_Type type() const  { return VMOp_PrintMetadata; }
 414   void doit();
 415 };
 416 
 417 class DeadlockCycle;
 418 class VM_FindDeadlocks: public VM_Operation {
 419  private:
 420   bool              _concurrent_locks;
 421   DeadlockCycle*    _deadlocks;
 422   outputStream*     _out;
 423   ThreadsListSetter _setter;  // Helper to set hazard ptr in the originating thread
 424                               // which protects the JavaThreads in _deadlocks.
 425 
 426  public:
 427   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _out(NULL), _deadlocks(NULL), _setter() {};
 428   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _out(st), _deadlocks(NULL) {};
 429   ~VM_FindDeadlocks();
 430 
 431   DeadlockCycle* result()      { return _deadlocks; };
 432   VMOp_Type type() const       { return VMOp_FindDeadlocks; }
 433   void doit();
 434 };
 435 
 436 class ThreadDumpResult;
 437 class ThreadSnapshot;
 438 class ThreadConcurrentLocks;
 439 
 440 class VM_ThreadDump : public VM_Operation {
 441  private:
 442   ThreadDumpResult*              _result;
 443   int                            _num_threads;
 444   GrowableArray<instanceHandle>* _threads;
 445   int                            _max_depth;
 446   bool                           _with_locked_monitors;
 447   bool                           _with_locked_synchronizers;
 448 
 449   ThreadSnapshot* snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl);
 450 
 451  public:
 452   VM_ThreadDump(ThreadDumpResult* result,
 453                 int max_depth,  // -1 indicates entire stack
 454                 bool with_locked_monitors,
 455                 bool with_locked_synchronizers);
 456 
 457   VM_ThreadDump(ThreadDumpResult* result,
 458                 GrowableArray<instanceHandle>* threads,
 459                 int num_threads, // -1 indicates entire stack
 460                 int max_depth,
 461                 bool with_locked_monitors,
 462                 bool with_locked_synchronizers);
 463 
 464   VMOp_Type type() const { return VMOp_ThreadDump; }
 465   void doit();
 466   bool doit_prologue();
 467   void doit_epilogue();
 468 };
 469 
 470 
 471 class VM_Exit: public VM_Operation {
 472  private:
 473   int  _exit_code;
 474   static volatile bool _vm_exited;
 475   static Thread * volatile _shutdown_thread;
 476   static void wait_if_vm_exited();
 477  public:
 478   VM_Exit(int exit_code) {
 479     _exit_code = exit_code;
 480   }
 481   static int wait_for_threads_in_native_to_block();
 482   static int set_vm_exited();
 483   static bool vm_exited()                      { return _vm_exited; }
 484   static Thread * shutdown_thread()            { return _shutdown_thread; }
 485   static void block_if_vm_exited() {
 486     if (_vm_exited) {
 487       wait_if_vm_exited();
 488     }
 489   }
 490   VMOp_Type type() const { return VMOp_Exit; }
 491   void doit();
 492 };
 493 
 494 class VM_PrintCompileQueue: public VM_Operation {
 495  private:
 496   outputStream* _out;
 497 
 498  public:
 499   VM_PrintCompileQueue(outputStream* st) : _out(st) {}
 500   VMOp_Type type() const { return VMOp_PrintCompileQueue; }
 501   Mode evaluation_mode() const { return _safepoint; }
 502   void doit();
 503 };
 504 
 505 #if INCLUDE_SERVICES
 506 class VM_PrintClassHierarchy: public VM_Operation {
 507  private:
 508   outputStream* _out;
 509   bool _print_interfaces;
 510   bool _print_subclasses;
 511   char* _classname;
 512 
 513  public:
 514   VM_PrintClassHierarchy(outputStream* st, bool print_interfaces, bool print_subclasses, char* classname) :
 515     _out(st), _print_interfaces(print_interfaces), _print_subclasses(print_subclasses),
 516     _classname(classname) {}
 517   VMOp_Type type() const { return VMOp_PrintClassHierarchy; }
 518   void doit();
 519 };
 520 #endif // INCLUDE_SERVICES
 521 
 522 #endif // SHARE_VM_RUNTIME_VM_OPERATIONS_HPP