1 /*

        2  * Copyright (c) 1997, 2009, 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,

       20  * CA 94065 USA or visit www.oracle.com if you need additional information or

       21  * have any questions.

       22  *

       23  */

       24 

       25 // The following classes are used for operations

       26 // initiated by a Java thread but that must

       27 // take place in the VMThread.

       28 

       29 #define VM_OP_ENUM(type)   VMOp_##type,

       30 

       31 // Note: When new VM_XXX comes up, add 'XXX' to the template table.

       32 #define VM_OPS_DO(template)                       \

       33   template(Dummy)                                 \

       34   template(ThreadStop)                            \

       35   template(ThreadDump)                            \

       36   template(PrintThreads)                          \

       37   template(FindDeadlocks)                         \

       38   template(ForceSafepoint)                        \

       39   template(ForceAsyncSafepoint)                   \

       40   template(Deoptimize)                            \

       41   template(DeoptimizeFrame)                       \

       42   template(DeoptimizeAll)                         \

       43   template(ZombieAll)                             \

       44   template(HandleFullCodeCache)                   \

       45   template(Verify)                                \

       46   template(PrintJNI)                              \

       47   template(HeapDumper)                            \

       48   template(DeoptimizeTheWorld)                    \

       49   template(GC_HeapInspection)                     \

       50   template(GenCollectFull)                        \

       51   template(GenCollectFullConcurrent)              \

       52   template(GenCollectForAllocation)               \

       53   template(GenCollectForPermanentAllocation)      \

       54   template(ParallelGCFailedAllocation)            \

       55   template(ParallelGCFailedPermanentAllocation)   \

       56   template(ParallelGCSystemGC)                    \

       57   template(CGC_Operation)                         \

       58   template(CMS_Initial_Mark)                      \

       59   template(CMS_Final_Remark)                      \

       60   template(G1CollectFull)                         \

       61   template(G1CollectForAllocation)                \

       62   template(G1IncCollectionPause)                  \

       63   template(EnableBiasedLocking)                   \

       64   template(RevokeBias)                            \

       65   template(BulkRevokeBias)                        \

       66   template(PopulateDumpSharedSpace)               \

       67   template(JNIFunctionTableCopier)                \

       68   template(RedefineClasses)                       \

       69   template(GetOwnedMonitorInfo)                   \

       70   template(GetObjectMonitorUsage)                 \

       71   template(GetCurrentContendedMonitor)            \

       72   template(GetStackTrace)                         \

       73   template(GetMultipleStackTraces)                \

       74   template(GetAllStackTraces)                     \

       75   template(GetThreadListStackTraces)              \

       76   template(GetFrameCount)                         \

       77   template(GetFrameLocation)                      \

       78   template(ChangeBreakpoints)                     \

       79   template(GetOrSetLocal)                         \

       80   template(GetCurrentLocation)                    \

       81   template(EnterInterpOnlyMode)                   \

       82   template(ChangeSingleStep)                      \

       83   template(HeapWalkOperation)                     \

       84   template(HeapIterateOperation)                  \

       85   template(ReportJavaOutOfMemory)                 \

       86   template(Exit)                                  \

       87 

       88 class VM_Operation: public CHeapObj {

       89  public:

       90   enum Mode {

       91     _safepoint,       // blocking,        safepoint, vm_op C-heap allocated

       92     _no_safepoint,    // blocking,     no safepoint, vm_op C-Heap allocated

       93     _concurrent,      // non-blocking, no safepoint, vm_op C-Heap allocated

       94     _async_safepoint  // non-blocking,    safepoint, vm_op C-Heap allocated

       95   };

       96 

       97   enum VMOp_Type {

       98     VM_OPS_DO(VM_OP_ENUM)

       99     VMOp_Terminating

      100   };

      101 

      102  private:

      103   Thread*         _calling_thread;

      104   ThreadPriority  _priority;

      105   long            _timestamp;

      106   VM_Operation*   _next;

      107   VM_Operation*   _prev;

      108 

      109   // The VM operation name array

      110   static const char* _names[];

      111 

      112  public:

      113   VM_Operation()  { _calling_thread = NULL; _next = NULL; _prev = NULL; }

      114   virtual ~VM_Operation() {}

      115 

      116   // VM operation support (used by VM thread)

      117   Thread* calling_thread() const                 { return _calling_thread; }

      118   ThreadPriority priority()                      { return _priority; }

      119   void set_calling_thread(Thread* thread, ThreadPriority priority);

      120 

      121   long timestamp() const              { return _timestamp; }

      122   void set_timestamp(long timestamp)  { _timestamp = timestamp; }

      123 

      124   // Called by VM thread - does in turn invoke doit(). Do not override this

      125   void evaluate();

      126 

      127   // evaluate() is called by the VMThread and in turn calls doit().

      128   // If the thread invoking VMThread::execute((VM_Operation*) is a JavaThread,

      129   // doit_prologue() is called in that thread before transferring control to

      130   // the VMThread.

      131   // If doit_prologue() returns true the VM operation will proceed, and

      132   // doit_epilogue() will be called by the JavaThread once the VM operation

      133   // completes. If doit_prologue() returns false the VM operation is cancelled.

      134   virtual void doit()                            = 0;

      135   virtual bool doit_prologue()                   { return true; };

      136   virtual void doit_epilogue()                   {}; // Note: Not called if mode is: _concurrent

      137 

      138   // Type test

      139   virtual bool is_methodCompiler() const         { return false; }

      140 

      141   // Linking

      142   VM_Operation *next() const                     { return _next; }

      143   VM_Operation *prev() const                     { return _prev; }

      144   void set_next(VM_Operation *next)              { _next = next; }

      145   void set_prev(VM_Operation *prev)              { _prev = prev; }

      146 

      147   // Configuration. Override these appropriatly in subclasses.

      148   virtual VMOp_Type type() const = 0;

      149   virtual Mode evaluation_mode() const            { return _safepoint; }

      150   virtual bool allow_nested_vm_operations() const { return false; }

      151   virtual bool is_cheap_allocated() const         { return false; }

      152   virtual void oops_do(OopClosure* f)              { /* do nothing */ };

      153 

      154   // CAUTION: <don't hang yourself with following rope>

      155   // If you override these methods, make sure that the evaluation

      156   // of these methods is race-free and non-blocking, since these

      157   // methods may be evaluated either by the mutators or by the

      158   // vm thread, either concurrently with mutators or with the mutators

      159   // stopped. In other words, taking locks is verboten, and if there

      160   // are any races in evaluating the conditions, they'd better be benign.

      161   virtual bool evaluate_at_safepoint() const {

      162     return evaluation_mode() == _safepoint  ||

      163            evaluation_mode() == _async_safepoint;

      164   }

      165   virtual bool evaluate_concurrently() const {

      166     return evaluation_mode() == _concurrent ||

      167            evaluation_mode() == _async_safepoint;

      168   }

      169 

      170   // Debugging

      171   void print_on_error(outputStream* st) const;

      172   const char* name() const { return _names[type()]; }

      173   static const char* name(int type) {

      174     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");

      175     return _names[type];

      176   }

      177 #ifndef PRODUCT

      178   void print_on(outputStream* st) const { print_on_error(st); }

      179 #endif

      180 };

      181 

      182 class VM_ThreadStop: public VM_Operation {

      183  private:

      184   oop     _thread;        // The Thread that the Throwable is thrown against

      185   oop     _throwable;     // The Throwable thrown at the target Thread

      186  public:

      187   // All oops are passed as JNI handles, since there is no guarantee that a GC might happen before the

      188   // VM operation is executed.

      189   VM_ThreadStop(oop thread, oop throwable) {

      190     _thread    = thread;

      191     _throwable = throwable;

      192   }

      193   VMOp_Type type() const                         { return VMOp_ThreadStop; }

      194   oop target_thread() const                      { return _thread; }

      195   oop throwable() const                          { return _throwable;}

      196   void doit();

      197   // We deoptimize if top-most frame is compiled - this might require a C2I adapter to be generated

      198   bool allow_nested_vm_operations() const        { return true; }

      199   Mode evaluation_mode() const                   { return _async_safepoint; }

      200   bool is_cheap_allocated() const                { return true; }

      201 

      202   // GC support

      203   void oops_do(OopClosure* f) {

      204     f->do_oop(&_thread); f->do_oop(&_throwable);

      205   }

      206 };

      207 

      208 // dummy vm op, evaluated just to force a safepoint

      209 class VM_ForceSafepoint: public VM_Operation {

      210  public:

      211   VM_ForceSafepoint() {}

      212   void doit()         {}

      213   VMOp_Type type() const { return VMOp_ForceSafepoint; }

      214 };

      215 

      216 // dummy vm op, evaluated just to force a safepoint

      217 class VM_ForceAsyncSafepoint: public VM_Operation {

      218  public:

      219   VM_ForceAsyncSafepoint() {}

      220   void doit()              {}

      221   VMOp_Type type() const                         { return VMOp_ForceAsyncSafepoint; }

      222   Mode evaluation_mode() const                   { return _async_safepoint; }

      223   bool is_cheap_allocated() const                { return true; }

      224 };

      225 

      226 class VM_Deoptimize: public VM_Operation {

      227  public:

      228   VM_Deoptimize() {}

      229   VMOp_Type type() const                        { return VMOp_Deoptimize; }

      230   void doit();

      231   bool allow_nested_vm_operations() const        { return true; }

      232 };

      233 

      234 class VM_DeoptimizeFrame: public VM_Operation {

      235  private:

      236   JavaThread* _thread;

      237   intptr_t*   _id;

      238  public:

      239   VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id);

      240   VMOp_Type type() const                         { return VMOp_DeoptimizeFrame; }

      241   void doit();

      242   bool allow_nested_vm_operations() const        { return true;  }

      243 };

      244 

      245 class VM_HandleFullCodeCache: public VM_Operation {

      246  private:

      247   bool  _is_full;

      248  public:

      249   VM_HandleFullCodeCache(bool is_full)           { _is_full = is_full; }

      250   VMOp_Type type() const                         { return VMOp_HandleFullCodeCache; }

      251   void doit();

      252   bool allow_nested_vm_operations() const        { return true; }

      253 };

      254 

      255 #ifndef PRODUCT

      256 class VM_DeoptimizeAll: public VM_Operation {

      257  private:

      258   KlassHandle _dependee;

      259  public:

      260   VM_DeoptimizeAll() {}

      261   VMOp_Type type() const                         { return VMOp_DeoptimizeAll; }

      262   void doit();

      263   bool allow_nested_vm_operations() const        { return true; }

      264 };

      265 

      266 

      267 class VM_ZombieAll: public VM_Operation {

      268  public:

      269   VM_ZombieAll() {}

      270   VMOp_Type type() const                         { return VMOp_ZombieAll; }

      271   void doit();

      272   bool allow_nested_vm_operations() const        { return true; }

      273 };

      274 #endif // PRODUCT

      275 

      276 class VM_Verify: public VM_Operation {

      277  private:

      278   KlassHandle _dependee;

      279  public:

      280   VM_Verify() {}

      281   VMOp_Type type() const { return VMOp_Verify; }

      282   void doit();

      283 };

      284 

      285 

      286 class VM_PrintThreads: public VM_Operation {

      287  private:

      288   outputStream* _out;

      289   bool _print_concurrent_locks;

      290  public:

      291   VM_PrintThreads()                                                { _out = tty; _print_concurrent_locks = PrintConcurrentLocks; }

      292   VM_PrintThreads(outputStream* out, bool print_concurrent_locks)  { _out = out; _print_concurrent_locks = print_concurrent_locks; }

      293   VMOp_Type type() const                                           {  return VMOp_PrintThreads; }

      294   void doit();

      295   bool doit_prologue();

      296   void doit_epilogue();

      297 };

      298 

      299 class VM_PrintJNI: public VM_Operation {

      300  private:

      301   outputStream* _out;

      302  public:

      303   VM_PrintJNI()                         { _out = tty; }

      304   VM_PrintJNI(outputStream* out)        { _out = out; }

      305   VMOp_Type type() const                { return VMOp_PrintJNI; }

      306   void doit();

      307 };

      308 

      309 class DeadlockCycle;

      310 class VM_FindDeadlocks: public VM_Operation {

      311  private:

      312   bool           _concurrent_locks;

      313   DeadlockCycle* _deadlocks;

      314   outputStream*  _out;

      315 

      316  public:

      317   VM_FindDeadlocks(bool concurrent_locks) :  _concurrent_locks(concurrent_locks), _out(NULL), _deadlocks(NULL) {};

      318   VM_FindDeadlocks(outputStream* st) : _concurrent_locks(true), _out(st), _deadlocks(NULL) {};

      319   ~VM_FindDeadlocks();

      320 

      321   DeadlockCycle* result()      { return _deadlocks; };

      322   VMOp_Type type() const       { return VMOp_FindDeadlocks; }

      323   void doit();

      324   bool doit_prologue();

      325 };

      326 

      327 class ThreadDumpResult;

      328 class ThreadSnapshot;

      329 class ThreadConcurrentLocks;

      330 

      331 class VM_ThreadDump : public VM_Operation {

      332  private:

      333   ThreadDumpResult*              _result;

      334   int                            _num_threads;

      335   GrowableArray<instanceHandle>* _threads;

      336   int                            _max_depth;

      337   bool                           _with_locked_monitors;

      338   bool                           _with_locked_synchronizers;

      339 

      340   ThreadSnapshot* snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl);

      341 

      342  public:

      343   VM_ThreadDump(ThreadDumpResult* result,

      344                 int max_depth,  // -1 indicates entire stack

      345                 bool with_locked_monitors,

      346                 bool with_locked_synchronizers);

      347 

      348   VM_ThreadDump(ThreadDumpResult* result,

      349                 GrowableArray<instanceHandle>* threads,

      350                 int num_threads, // -1 indicates entire stack

      351                 int max_depth,

      352                 bool with_locked_monitors,

      353                 bool with_locked_synchronizers);

      354 

      355   VMOp_Type type() const { return VMOp_ThreadDump; }

      356   void doit();

      357   bool doit_prologue();

      358   void doit_epilogue();

      359 };

      360 

      361 

      362 class VM_Exit: public VM_Operation {

      363  private:

      364   int  _exit_code;

      365   static volatile bool _vm_exited;

      366   static Thread * _shutdown_thread;

      367   static void wait_if_vm_exited();

      368  public:

      369   VM_Exit(int exit_code) {

      370     _exit_code = exit_code;

      371   }

      372   static int wait_for_threads_in_native_to_block();

      373   static int set_vm_exited();

      374   static bool vm_exited()                      { return _vm_exited; }

      375   static void block_if_vm_exited() {

      376     if (_vm_exited) {

      377       wait_if_vm_exited();

      378     }

      379   }

      380   VMOp_Type type() const { return VMOp_Exit; }

      381   void doit();

      382 };