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