1 /*
   2  * Copyright (c) 1997, 2019, 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_RUNTIME_VMOPERATIONS_HPP
  26 #define SHARE_RUNTIME_VMOPERATIONS_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(None)                                  \
  44   template(Cleanup)                               \
  45   template(ThreadStop)                            \
  46   template(ThreadDump)                            \
  47   template(PrintThreads)                          \
  48   template(FindDeadlocks)                         \
  49   template(ClearICs)                              \
  50   template(ForceSafepoint)                        \
  51   template(ForceAsyncSafepoint)                   \
  52   template(Deoptimize)                            \
  53   template(DeoptimizeFrame)                       \
  54   template(DeoptimizeAll)                         \
  55   template(ZombieAll)                             \
  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(CMS_Initial_Mark)                      \
  68   template(CMS_Final_Remark)                      \
  69   template(G1CollectForAllocation)                \
  70   template(G1CollectFull)                         \
  71   template(G1Concurrent)                          \
  72   template(ZMarkStart)                            \
  73   template(ZMarkEnd)                              \
  74   template(ZRelocateStart)                        \
  75   template(ZVerify)                               \
  76   template(HandshakeOneThread)                    \
  77   template(HandshakeAllThreads)                   \
  78   template(HandshakeFallback)                     \
  79   template(EnableBiasedLocking)                   \
  80   template(RevokeBias)                            \
  81   template(BulkRevokeBias)                        \
  82   template(PopulateDumpSharedSpace)               \
  83   template(JNIFunctionTableCopier)                \
  84   template(RedefineClasses)                       \
  85   template(UpdateForPopTopFrame)                  \
  86   template(SetFramePop)                           \
  87   template(GetOwnedMonitorInfo)                   \
  88   template(GetObjectMonitorUsage)                 \
  89   template(GetCurrentContendedMonitor)            \
  90   template(GetStackTrace)                         \
  91   template(GetMultipleStackTraces)                \
  92   template(GetAllStackTraces)                     \
  93   template(GetThreadListStackTraces)              \
  94   template(GetFrameCount)                         \
  95   template(GetFrameLocation)                      \
  96   template(ChangeBreakpoints)                     \
  97   template(GetOrSetLocal)                         \
  98   template(GetCurrentLocation)                    \
  99   template(EnterInterpOnlyMode)                   \
 100   template(ChangeSingleStep)                      \
 101   template(HeapWalkOperation)                     \
 102   template(HeapIterateOperation)                  \
 103   template(ReportJavaOutOfMemory)                 \
 104   template(JFRCheckpoint)                         \
 105   template(ShenandoahFullGC)                      \
 106   template(ShenandoahInitMark)                    \
 107   template(ShenandoahFinalMarkStartEvac)          \
 108   template(ShenandoahFinalEvac)                   \
 109   template(ShenandoahInitTraversalGC)             \
 110   template(ShenandoahFinalTraversalGC)            \
 111   template(ShenandoahInitUpdateRefs)              \
 112   template(ShenandoahFinalUpdateRefs)             \
 113   template(ShenandoahDegeneratedGC)               \
 114   template(Exit)                                  \
 115   template(LinuxDllLoad)                          \
 116   template(RotateGCLog)                           \
 117   template(WhiteBoxOperation)                     \
 118   template(JVMCIResizeCounters)                   \
 119   template(ClassLoaderStatsOperation)             \
 120   template(ClassLoaderHierarchyOperation)         \
 121   template(DumpHashtable)                         \
 122   template(DumpTouchedMethods)                    \
 123   template(MarkActiveNMethods)                    \
 124   template(PrintCompileQueue)                     \
 125   template(PrintClassHierarchy)                   \
 126   template(ThreadSuspend)                         \
 127   template(ThreadsSuspendJVMTI)                   \
 128   template(ICBufferFull)                          \
 129   template(ScavengeMonitors)                      \
 130   template(PrintMetadata)                         \
 131   template(GTestExecuteAtSafepoint)               \
 132   template(JFROldObject)                          \
 133 
 134 class VM_Operation: public CHeapObj<mtInternal> {
 135  public:
 136   enum Mode {
 137     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated
 138     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated
 139     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated
 140     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated
 141   };
 142 
 143   enum VMOp_Type {
 144     VM_OPS_DO(VM_OP_ENUM)
 145     VMOp_Terminating
 146   };
 147 
 148  private:
 149   Thread*         _calling_thread;
 150   ThreadPriority  _priority;
 151   long            _timestamp;
 152   VM_Operation*   _next;
 153   VM_Operation*   _prev;
 154 
 155   // The VM operation name array
 156   static const char* _names[];
 157 
 158  public:
 159   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }
 160   virtual ~VM_Operation() {}
 161 
 162   // VM operation support (used by VM thread)
 163   Thread* calling_thread() const                 { return _calling_thread; }
 164   ThreadPriority priority()                      { return _priority; }
 165   void set_calling_thread(Thread* thread, ThreadPriority priority);
 166 
 167   long timestamp() const              { return _timestamp; }
 168   void set_timestamp(long timestamp)  { _timestamp = timestamp; }
 169 
 170   // Called by VM thread - does in turn invoke doit(). Do not override this
 171   void evaluate();
 172 
 173   // evaluate() is called by the VMThread and in turn calls doit().
 174   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,
 175   // doit_prologue() is called in that thread before transferring control to
 176   // the VMThread.
 177   // If doit_prologue() returns true the VM operation will proceed, and
 178   // doit_epilogue() will be called by the JavaThread once the VM operation
 179   // completes. If doit_prologue() returns false the VM operation is cancelled.
 180   virtual void doit()                            = 0;
 181   virtual bool doit_prologue()                   { return true; };
 182   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent
 183 
 184   // Type test
 185   virtual bool is_methodCompiler() const         { return false; }
 186 
 187   // Linking
 188   VM_Operation *next() const                     { return _next; }
 189   VM_Operation *prev() const                     { return _prev; }
 190   void set_next(VM_Operation *next)              { _next = next; }
 191   void set_prev(VM_Operation *prev)              { _prev = prev; }
 192 
 193   // Configuration. Override these appropriately in subclasses.
 194   virtual VMOp_Type type() const = 0;
 195   virtual Mode evaluation_mode() const            { return _safepoint; }
 196   virtual bool allow_nested_vm_operations() const { return false; }
 197   virtual bool is_cheap_allocated() const         { return false; }
 198   virtual void oops_do(OopClosure* f)              { /* do nothing */ };
 199 
 200   // CAUTION: <don't hang yourself with following rope>
 201   // If you override these methods, make sure that the evaluation
 202   // of these methods is race-free and non-blocking, since these
 203   // methods may be evaluated either by the mutators or by the
 204   // vm thread, either concurrently with mutators or with the mutators
 205   // stopped. In other words, taking locks is verboten, and if there
 206   // are any races in evaluating the conditions, they'd better be benign.
 207   virtual bool evaluate_at_safepoint() const {
 208     return evaluation_mode() == _safepoint  ||
 209            evaluation_mode() == _async_safepoint;
 210   }
 211   virtual bool evaluate_concurrently() const {
 212     return evaluation_mode() == _concurrent ||
 213            evaluation_mode() == _async_safepoint;
 214   }
 215 
 216   static const char* mode_to_string(Mode mode);
 217 
 218   // Debugging
 219   virtual void print_on_error(outputStream* st) const;
 220   virtual const char* name() const  { return _names[type()]; }
 221   static const char* name(int type) {
 222     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");
 223     return _names[type];
 224   }
 225 #ifndef PRODUCT
 226   void print_on(outputStream* st) const { print_on_error(st); }
 227 #endif
 228 };
 229 
 230 class VM_None: public VM_Operation {
 231   const char* _reason;
 232  public:
 233   VM_None(const char* reason) : _reason(reason) {}
 234   const char* name() const { return _reason; }
 235   VMOp_Type type() const { return VMOp_None; }
 236   void doit() {};
 237 };
 238 
 239 class VM_Cleanup: public VM_Operation {
 240  public:
 241   VMOp_Type type() const { return VMOp_Cleanup; }
 242   void doit() {};
 243 };
 244 
 245 class VM_ThreadStop: public VM_Operation {
 246  private:
 247   oop     _thread;        // The Thread that the Throwable is thrown against
 248   oop     _throwable;     // The Throwable thrown at the target Thread
 249  public:
 250   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the
 251   // VM operation is executed.
 252   VM_ThreadStop(oop thread, oop throwable) {
 253     _thread    = thread;
 254     _throwable = throwable;
 255   }
 256   VMOp_Type type() const                         { return VMOp_ThreadStop; }
 257   oop target_thread() const                      { return _thread; }
 258   oop throwable() const                          { return _throwable;}
 259   void doit();
 260   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated
 261   bool allow_nested_vm_operations() const        { return true; }
 262   Mode evaluation_mode() const                   { return _async_safepoint; }
 263   bool is_cheap_allocated() const                { return true; }
 264 
 265   // GC support
 266   void oops_do(OopClosure* f) {
 267     f->do_oop(&_thread); f->do_oop(&_throwable);
 268   }
 269 };
 270 
 271 class VM_ClearICs: public VM_Operation {
 272  private:
 273   bool _preserve_static_stubs;
 274  public:
 275   VM_ClearICs(bool preserve_static_stubs) { _preserve_static_stubs = preserve_static_stubs; }
 276   void doit();
 277   VMOp_Type type() const { return VMOp_ClearICs; }
 278 };
 279 
 280 // empty vm op, evaluated just to force a safepoint
 281 class VM_ForceSafepoint: public VM_Operation {
 282  public:
 283   void doit()         {}
 284   VMOp_Type type() const { return VMOp_ForceSafepoint; }
 285 };
 286 
 287 // empty vm op, when forcing a safepoint to suspend a thread
 288 class VM_ThreadSuspend: public VM_ForceSafepoint {
 289  public:
 290   VMOp_Type type() const { return VMOp_ThreadSuspend; }
 291 };
 292 
 293 // empty vm op, when forcing a safepoint to suspend threads from jvmti
 294 class VM_ThreadsSuspendJVMTI: public VM_ForceSafepoint {
 295  public:
 296   VMOp_Type type() const { return VMOp_ThreadsSuspendJVMTI; }
 297 };
 298 
 299 // empty vm op, when forcing a safepoint due to inline cache buffers being full
 300 class VM_ICBufferFull: public VM_ForceSafepoint {
 301  public:
 302   VMOp_Type type() const { return VMOp_ICBufferFull; }
 303 };
 304 
 305 // empty asynchronous vm op, when forcing a safepoint to scavenge monitors
 306 class VM_ScavengeMonitors: public VM_ForceSafepoint {
 307  public:
 308   VMOp_Type type() const                         { return VMOp_ScavengeMonitors; }
 309   Mode evaluation_mode() const                   { return _async_safepoint; }
 310   bool is_cheap_allocated() const                { return true; }
 311 };
 312 
 313 // Base class for invoking parts of a gtest in a safepoint.
 314 // Derived classes provide the doit method.
 315 // Typically also need to transition the gtest thread from native to VM.
 316 class VM_GTestExecuteAtSafepoint: public VM_Operation {
 317  public:
 318   VMOp_Type type() const                         { return VMOp_GTestExecuteAtSafepoint; }
 319 
 320  protected:
 321   VM_GTestExecuteAtSafepoint() {}
 322 };
 323 
 324 class VM_Deoptimize: public VM_Operation {
 325  public:
 326   VM_Deoptimize() {}
 327   VMOp_Type type() const                        { return VMOp_Deoptimize; }
 328   void doit();
 329   bool allow_nested_vm_operations() const        { return true; }
 330 };
 331 
 332 class VM_MarkActiveNMethods: public VM_Operation {
 333  public:
 334   VM_MarkActiveNMethods() {}
 335   VMOp_Type type() const                         { return VMOp_MarkActiveNMethods; }
 336   void doit();
 337   bool allow_nested_vm_operations() const        { return true; }
 338 };
 339 
 340 // Deopt helper that can deoptimize frames in threads other than the
 341 // current thread.  Only used through Deoptimization::deoptimize_frame.
 342 class VM_DeoptimizeFrame: public VM_Operation {
 343   friend class Deoptimization;
 344 
 345  private:
 346   JavaThread* _thread;
 347   intptr_t*   _id;
 348   int _reason;
 349   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id, int reason);
 350 
 351  public:
 352   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }
 353   void doit();
 354   bool allow_nested_vm_operations() const        { return true;  }
 355 };
 356 
 357 #ifndef PRODUCT
 358 class VM_DeoptimizeAll: public VM_Operation {
 359  private:
 360   Klass* _dependee;
 361  public:
 362   VM_DeoptimizeAll() {}
 363   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }
 364   void doit();
 365   bool allow_nested_vm_operations() const        { return true; }
 366 };
 367 
 368 
 369 class VM_ZombieAll: public VM_Operation {
 370  public:
 371   VM_ZombieAll() {}
 372   VMOp_Type type() const                         { return VMOp_ZombieAll; }
 373   void doit();
 374   bool allow_nested_vm_operations() const        { return true; }
 375 };
 376 #endif // PRODUCT
 377 
 378 class VM_Verify: public VM_Operation {
 379  public:
 380   VMOp_Type type() const { return VMOp_Verify; }
 381   void doit();
 382 };
 383 
 384 
 385 class VM_PrintThreads: public VM_Operation {
 386  private:
 387   outputStream* _out;
 388   bool _print_concurrent_locks;
 389   bool _print_extended_info;
 390  public:
 391   VM_PrintThreads()
 392     : _out(tty), _print_concurrent_locks(PrintConcurrentLocks), _print_extended_info(false)
 393   {}
 394   VM_PrintThreads(outputStream* out, bool print_concurrent_locks, bool print_extended_info)
 395     : _out(out), _print_concurrent_locks(print_concurrent_locks), _print_extended_info(print_extended_info)
 396   {}
 397   VMOp_Type type() const {
 398     return VMOp_PrintThreads;
 399   }
 400   void doit();
 401   bool doit_prologue();
 402   void doit_epilogue();
 403 };
 404 
 405 class VM_PrintJNI: public VM_Operation {
 406  private:
 407   outputStream* _out;
 408  public:
 409   VM_PrintJNI()                         { _out = tty; }
 410   VM_PrintJNI(outputStream* out)        { _out = out; }
 411   VMOp_Type type() const                { return VMOp_PrintJNI; }
 412   void doit();
 413 };
 414 
 415 class VM_PrintMetadata : public VM_Operation {
 416  private:
 417   outputStream* const _out;
 418   const size_t        _scale;
 419   const int           _flags;
 420 
 421  public:
 422   VM_PrintMetadata(outputStream* out, size_t scale, int flags)
 423     : _out(out), _scale(scale), _flags(flags)
 424   {};
 425 
 426   VMOp_Type type() const  { return VMOp_PrintMetadata; }
 427   void doit();
 428 };
 429 
 430 class DeadlockCycle;
 431 class VM_FindDeadlocks: public VM_Operation {
 432  private:
 433   bool              _concurrent_locks;
 434   DeadlockCycle*    _deadlocks;
 435   outputStream*     _out;
 436   ThreadsListSetter _setter;  // Helper to set hazard ptr in the originating thread
 437                               // which protects the JavaThreads in _deadlocks.
 438 
 439  public:
 440   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _deadlocks(NULL), _out(NULL), _setter() {};
 441   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _deadlocks(NULL), _out(st) {};
 442   ~VM_FindDeadlocks();
 443 
 444   DeadlockCycle* result()      { return _deadlocks; };
 445   VMOp_Type type() const       { return VMOp_FindDeadlocks; }
 446   void doit();
 447 };
 448 
 449 class ThreadDumpResult;
 450 class ThreadSnapshot;
 451 class ThreadConcurrentLocks;
 452 
 453 class VM_ThreadDump : public VM_Operation {
 454  private:
 455   ThreadDumpResult*              _result;
 456   int                            _num_threads;
 457   GrowableArray<instanceHandle>* _threads;
 458   int                            _max_depth;
 459   bool                           _with_locked_monitors;
 460   bool                           _with_locked_synchronizers;
 461 
 462   void snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl);
 463 
 464  public:
 465   VM_ThreadDump(ThreadDumpResult* result,
 466                 int max_depth,  // -1 indicates entire stack
 467                 bool with_locked_monitors,
 468                 bool with_locked_synchronizers);
 469 
 470   VM_ThreadDump(ThreadDumpResult* result,
 471                 GrowableArray<instanceHandle>* threads,
 472                 int num_threads, // -1 indicates entire stack
 473                 int max_depth,
 474                 bool with_locked_monitors,
 475                 bool with_locked_synchronizers);
 476 
 477   VMOp_Type type() const { return VMOp_ThreadDump; }
 478   void doit();
 479   bool doit_prologue();
 480   void doit_epilogue();
 481 };
 482 
 483 
 484 class VM_Exit: public VM_Operation {
 485  private:
 486   int  _exit_code;
 487   static volatile bool _vm_exited;
 488   static Thread * volatile _shutdown_thread;
 489   static void wait_if_vm_exited();
 490  public:
 491   VM_Exit(int exit_code) {
 492     _exit_code = exit_code;
 493   }
 494   static int wait_for_threads_in_native_to_block();
 495   static int set_vm_exited();
 496   static bool vm_exited()                      { return _vm_exited; }
 497   static Thread * shutdown_thread()            { return _shutdown_thread; }
 498   static void block_if_vm_exited() {
 499     if (_vm_exited) {
 500       wait_if_vm_exited();
 501     }
 502   }
 503   VMOp_Type type() const { return VMOp_Exit; }
 504   bool doit_prologue();
 505   void doit();
 506 };
 507 
 508 class VM_PrintCompileQueue: public VM_Operation {
 509  private:
 510   outputStream* _out;
 511 
 512  public:
 513   VM_PrintCompileQueue(outputStream* st) : _out(st) {}
 514   VMOp_Type type() const { return VMOp_PrintCompileQueue; }
 515   Mode evaluation_mode() const { return _safepoint; }
 516   void doit();
 517 };
 518 
 519 #if INCLUDE_SERVICES
 520 class VM_PrintClassHierarchy: public VM_Operation {
 521  private:
 522   outputStream* _out;
 523   bool _print_interfaces;
 524   bool _print_subclasses;
 525   char* _classname;
 526 
 527  public:
 528   VM_PrintClassHierarchy(outputStream* st, bool print_interfaces, bool print_subclasses, char* classname) :
 529     _out(st), _print_interfaces(print_interfaces), _print_subclasses(print_subclasses),
 530     _classname(classname) {}
 531   VMOp_Type type() const { return VMOp_PrintClassHierarchy; }
 532   void doit();
 533 };
 534 #endif // INCLUDE_SERVICES
 535 
 536 #endif // SHARE_RUNTIME_VMOPERATIONS_HPP