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(None)                                  \
  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(Verify)                                \
  56   template(PrintJNI)                              \
  57   template(HeapDumper)                            \
  58   template(DeoptimizeTheWorld)                    \
  59   template(CollectForMetadataAllocation)          \
  60   template(GC_HeapInspection)                     \
  61   template(GenCollectFull)                        \
  62   template(GenCollectFullConcurrent)              \
  63   template(GenCollectForAllocation)               \
  64   template(ParallelGCFailedAllocation)            \
  65   template(ParallelGCSystemGC)                    \
  66   template(CGC_Operation)                         \
  67   template(CMS_Initial_Mark)                      \
  68   template(CMS_Final_Remark)                      \
  69   template(G1CollectForAllocation)                \
  70   template(G1CollectFull)                         \
  71   template(ZOperation)                            \
  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(ClassLoaderHierarchyOperation)         \
 107   template(DumpHashtable)                         \
 108   template(DumpTouchedMethods)                    \
 109   template(MarkActiveNMethods)                    \
 110   template(PrintCompileQueue)                     \
 111   template(PrintClassHierarchy)                   \
 112   template(ThreadSuspend)                         \
 113   template(CTWThreshold)                          \
 114   template(ThreadsSuspendJVMTI)                   \
 115   template(ICBufferFull)                          \
 116   template(ScavengeMonitors)                      \
 117   template(PrintMetadata)                         \
 118   template(GTestExecuteAtSafepoint)               \
 119   template(VTBufferStats)                         \
 120 
 121 class VM_Operation: public CHeapObj<mtInternal> {
 122  public:
 123   enum Mode {
 124     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated
 125     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated
 126     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated
 127     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated
 128   };
 129 
 130   enum VMOp_Type {
 131     VM_OPS_DO(VM_OP_ENUM)
 132     VMOp_Terminating
 133   };
 134 
 135  private:
 136   Thread*         _calling_thread;
 137   ThreadPriority  _priority;
 138   long            _timestamp;
 139   VM_Operation*   _next;
 140   VM_Operation*   _prev;
 141 
 142   // The VM operation name array
 143   static const char* _names[];
 144 
 145  public:
 146   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }
 147   virtual ~VM_Operation() {}
 148 
 149   // VM operation support (used by VM thread)
 150   Thread* calling_thread() const                 { return _calling_thread; }
 151   ThreadPriority priority()                      { return _priority; }
 152   void set_calling_thread(Thread* thread, ThreadPriority priority);
 153 
 154   long timestamp() const              { return _timestamp; }
 155   void set_timestamp(long timestamp)  { _timestamp = timestamp; }
 156 
 157   // Called by VM thread - does in turn invoke doit(). Do not override this
 158   void evaluate();
 159 
 160   // evaluate() is called by the VMThread and in turn calls doit().
 161   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,
 162   // doit_prologue() is called in that thread before transferring control to
 163   // the VMThread.
 164   // If doit_prologue() returns true the VM operation will proceed, and
 165   // doit_epilogue() will be called by the JavaThread once the VM operation
 166   // completes. If doit_prologue() returns false the VM operation is cancelled.
 167   virtual void doit()                            = 0;
 168   virtual bool doit_prologue()                   { return true; };
 169   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent
 170 
 171   // Type test
 172   virtual bool is_methodCompiler() const         { return false; }
 173 
 174   // Linking
 175   VM_Operation *next() const                     { return _next; }
 176   VM_Operation *prev() const                     { return _prev; }
 177   void set_next(VM_Operation *next)              { _next = next; }
 178   void set_prev(VM_Operation *prev)              { _prev = prev; }
 179 
 180   // Configuration. Override these appropriately in subclasses.
 181   virtual VMOp_Type type() const = 0;
 182   virtual Mode evaluation_mode() const            { return _safepoint; }
 183   virtual bool allow_nested_vm_operations() const { return false; }
 184   virtual bool is_cheap_allocated() const         { return false; }
 185   virtual void oops_do(OopClosure* f)              { /* do nothing */ };
 186 
 187   // CAUTION: <don't hang yourself with following rope>
 188   // If you override these methods, make sure that the evaluation
 189   // of these methods is race-free and non-blocking, since these
 190   // methods may be evaluated either by the mutators or by the
 191   // vm thread, either concurrently with mutators or with the mutators
 192   // stopped. In other words, taking locks is verboten, and if there
 193   // are any races in evaluating the conditions, they'd better be benign.
 194   virtual bool evaluate_at_safepoint() const {
 195     return evaluation_mode() == _safepoint  ||
 196            evaluation_mode() == _async_safepoint;
 197   }
 198   virtual bool evaluate_concurrently() const {
 199     return evaluation_mode() == _concurrent ||
 200            evaluation_mode() == _async_safepoint;
 201   }
 202 
 203   static const char* mode_to_string(Mode mode);
 204 
 205   // Debugging
 206   virtual void print_on_error(outputStream* st) const;
 207   const char* name() const { return _names[type()]; }
 208   static const char* name(int type) {
 209     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");
 210     return _names[type];
 211   }
 212 #ifndef PRODUCT
 213   void print_on(outputStream* st) const { print_on_error(st); }
 214 #endif
 215 };
 216 
 217 class VM_ThreadStop: public VM_Operation {
 218  private:
 219   oop     _thread;        // The Thread that the Throwable is thrown against
 220   oop     _throwable;     // The Throwable thrown at the target Thread
 221  public:
 222   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the
 223   // VM operation is executed.
 224   VM_ThreadStop(oop thread, oop throwable) {
 225     _thread    = thread;
 226     _throwable = throwable;
 227   }
 228   VMOp_Type type() const                         { return VMOp_ThreadStop; }
 229   oop target_thread() const                      { return _thread; }
 230   oop throwable() const                          { return _throwable;}
 231   void doit();
 232   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated
 233   bool allow_nested_vm_operations() const        { return true; }
 234   Mode evaluation_mode() const                   { return _async_safepoint; }
 235   bool is_cheap_allocated() const                { return true; }
 236 
 237   // GC support
 238   void oops_do(OopClosure* f) {
 239     f->do_oop(&_thread); f->do_oop(&_throwable);
 240   }
 241 };
 242 
 243 class VM_ClearICs: public VM_Operation {
 244  private:
 245   bool _preserve_static_stubs;
 246  public:
 247   VM_ClearICs(bool preserve_static_stubs) { _preserve_static_stubs = preserve_static_stubs; }
 248   void doit();
 249   VMOp_Type type() const { return VMOp_ClearICs; }
 250 };
 251 
 252 // empty vm op, evaluated just to force a safepoint
 253 class VM_ForceSafepoint: public VM_Operation {
 254  public:
 255   void doit()         {}
 256   VMOp_Type type() const { return VMOp_ForceSafepoint; }
 257 };
 258 
 259 // empty vm op, when forcing a safepoint to suspend a thread
 260 class VM_ThreadSuspend: public VM_ForceSafepoint {
 261  public:
 262   VMOp_Type type() const { return VMOp_ThreadSuspend; }
 263 };
 264 
 265 // empty vm op, when forcing a safepoint due to ctw threshold is reached for the sweeper
 266 class VM_CTWThreshold: public VM_ForceSafepoint {
 267  public:
 268   VMOp_Type type() const { return VMOp_CTWThreshold; }
 269 };
 270 
 271 // empty vm op, when forcing a safepoint to suspend threads from jvmti
 272 class VM_ThreadsSuspendJVMTI: public VM_ForceSafepoint {
 273  public:
 274   VMOp_Type type() const { return VMOp_ThreadsSuspendJVMTI; }
 275 };
 276 
 277 // empty vm op, when forcing a safepoint due to inline cache buffers being full
 278 class VM_ICBufferFull: public VM_ForceSafepoint {
 279  public:
 280   VMOp_Type type() const { return VMOp_ICBufferFull; }
 281 };
 282 
 283 // empty asynchronous vm op, when forcing a safepoint to scavenge monitors
 284 class VM_ScavengeMonitors: public VM_ForceSafepoint {
 285  public:
 286   VMOp_Type type() const                         { return VMOp_ScavengeMonitors; }
 287   Mode evaluation_mode() const                   { return _async_safepoint; }
 288   bool is_cheap_allocated() const                { return true; }
 289 };
 290 
 291 // Base class for invoking parts of a gtest in a safepoint.
 292 // Derived classes provide the doit method.
 293 // Typically also need to transition the gtest thread from native to VM.
 294 class VM_GTestExecuteAtSafepoint: public VM_Operation {
 295  public:
 296   VMOp_Type type() const                         { return VMOp_GTestExecuteAtSafepoint; }
 297 
 298  protected:
 299   VM_GTestExecuteAtSafepoint() {}
 300 };
 301 
 302 class VM_Deoptimize: public VM_Operation {
 303  public:
 304   VM_Deoptimize() {}
 305   VMOp_Type type() const                        { return VMOp_Deoptimize; }
 306   void doit();
 307   bool allow_nested_vm_operations() const        { return true; }
 308 };
 309 
 310 class VM_MarkActiveNMethods: public VM_Operation {
 311  public:
 312   VM_MarkActiveNMethods() {}
 313   VMOp_Type type() const                         { return VMOp_MarkActiveNMethods; }
 314   void doit();
 315   bool allow_nested_vm_operations() const        { return true; }
 316 };
 317 
 318 // Deopt helper that can deoptimize frames in threads other than the
 319 // current thread.  Only used through Deoptimization::deoptimize_frame.
 320 class VM_DeoptimizeFrame: public VM_Operation {
 321   friend class Deoptimization;
 322 
 323  private:
 324   JavaThread* _thread;
 325   intptr_t*   _id;
 326   int _reason;
 327   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id, int reason);
 328 
 329  public:
 330   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }
 331   void doit();
 332   bool allow_nested_vm_operations() const        { return true;  }
 333 };
 334 
 335 #ifndef PRODUCT
 336 class VM_DeoptimizeAll: public VM_Operation {
 337  private:
 338   Klass* _dependee;
 339  public:
 340   VM_DeoptimizeAll() {}
 341   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }
 342   void doit();
 343   bool allow_nested_vm_operations() const        { return true; }
 344 };
 345 
 346 
 347 class VM_ZombieAll: public VM_Operation {
 348  public:
 349   VM_ZombieAll() {}
 350   VMOp_Type type() const                         { return VMOp_ZombieAll; }
 351   void doit();
 352   bool allow_nested_vm_operations() const        { return true; }
 353 };
 354 #endif // PRODUCT
 355 
 356 class VM_Verify: public VM_Operation {
 357  public:
 358   VMOp_Type type() const { return VMOp_Verify; }
 359   void doit();
 360 };
 361 
 362 
 363 class VM_PrintThreads: public VM_Operation {
 364  private:
 365   outputStream* _out;
 366   bool _print_concurrent_locks;
 367   bool _print_extended_info;
 368  public:
 369   VM_PrintThreads()
 370     : _out(tty), _print_concurrent_locks(PrintConcurrentLocks), _print_extended_info(false)
 371   {}
 372   VM_PrintThreads(outputStream* out, bool print_concurrent_locks, bool print_extended_info)
 373     : _out(out), _print_concurrent_locks(print_concurrent_locks), _print_extended_info(print_extended_info)
 374   {}
 375   VMOp_Type type() const {
 376     return VMOp_PrintThreads;
 377   }
 378   void doit();
 379   bool doit_prologue();
 380   void doit_epilogue();
 381 };
 382 
 383 class VM_PrintJNI: public VM_Operation {
 384  private:
 385   outputStream* _out;
 386  public:
 387   VM_PrintJNI()                         { _out = tty; }
 388   VM_PrintJNI(outputStream* out)        { _out = out; }
 389   VMOp_Type type() const                { return VMOp_PrintJNI; }
 390   void doit();
 391 };
 392 
 393 class VM_PrintMetadata : public VM_Operation {
 394  private:
 395   outputStream* const _out;
 396   const size_t        _scale;
 397   const int           _flags;
 398 
 399  public:
 400   VM_PrintMetadata(outputStream* out, size_t scale, int flags)
 401     : _out(out), _scale(scale), _flags(flags)
 402   {};
 403 
 404   VMOp_Type type() const  { return VMOp_PrintMetadata; }
 405   void doit();
 406 };
 407 
 408 class DeadlockCycle;
 409 class VM_FindDeadlocks: public VM_Operation {
 410  private:
 411   bool              _concurrent_locks;
 412   DeadlockCycle*    _deadlocks;
 413   outputStream*     _out;
 414   ThreadsListSetter _setter;  // Helper to set hazard ptr in the originating thread
 415                               // which protects the JavaThreads in _deadlocks.
 416 
 417  public:
 418   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _deadlocks(NULL), _out(NULL), _setter() {};
 419   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _deadlocks(NULL), _out(st) {};
 420   ~VM_FindDeadlocks();
 421 
 422   DeadlockCycle* result()      { return _deadlocks; };
 423   VMOp_Type type() const       { return VMOp_FindDeadlocks; }
 424   void doit();
 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