1 /*
   2  * Copyright (c) 1998, 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_PRIMS_JVMTIEXPORT_HPP
  26 #define SHARE_PRIMS_JVMTIEXPORT_HPP
  27 
  28 #include "jvmtifiles/jvmti.h"
  29 #include "memory/allocation.hpp"
  30 #include "memory/iterator.hpp"
  31 #include "oops/oop.hpp"
  32 #include "oops/oopsHierarchy.hpp"
  33 #include "runtime/frame.hpp"
  34 #include "runtime/handles.hpp"
  35 #include "utilities/globalDefinitions.hpp"
  36 #include "utilities/growableArray.hpp"
  37 #include "utilities/macros.hpp"
  38 
  39 // Must be included after jvmti.h.
  40 #include "jvmticmlr.h"
  41 
  42 // Forward declarations
  43 
  44 class JvmtiEventControllerPrivate;
  45 class JvmtiManageCapabilities;
  46 class JvmtiEnv;
  47 class JvmtiThreadState;
  48 
  49 #define JVMTI_SUPPORT_FLAG(key)                                           \
  50   private:                                                                \
  51   static bool  _##key;                                                    \
  52   public:                                                                 \
  53   inline static void set_##key(bool on) {                                 \
  54     JVMTI_ONLY(_##key = (on != 0));                                       \
  55     NOT_JVMTI(report_unsupported(on));                                    \
  56   }                                                                       \
  57   inline static bool key() {                                              \
  58     JVMTI_ONLY(return _##key);                                            \
  59     NOT_JVMTI(return false);                                              \
  60   }
  61 
  62 
  63 // This class contains the JVMTI interface for the rest of hotspot.
  64 //
  65 class JvmtiExport : public AllStatic {
  66   friend class VMStructs;
  67   friend class CompileReplay;
  68 
  69  private:
  70 
  71 #if INCLUDE_JVMTI
  72   static int         _field_access_count;
  73   static int         _field_modification_count;
  74 
  75   static bool        _can_access_local_variables;
  76   static bool        _can_hotswap_or_post_breakpoint;
  77   static bool        _can_modify_any_class;
  78   static bool        _can_walk_any_space;
  79 #endif // INCLUDE_JVMTI
  80 
  81   JVMTI_SUPPORT_FLAG(can_get_source_debug_extension)
  82   JVMTI_SUPPORT_FLAG(can_maintain_original_method_order)
  83   JVMTI_SUPPORT_FLAG(can_post_interpreter_events)
  84   JVMTI_SUPPORT_FLAG(can_post_on_exceptions)
  85   JVMTI_SUPPORT_FLAG(can_post_breakpoint)
  86   JVMTI_SUPPORT_FLAG(can_post_field_access)
  87   JVMTI_SUPPORT_FLAG(can_post_field_modification)
  88   JVMTI_SUPPORT_FLAG(can_post_method_entry)
  89   JVMTI_SUPPORT_FLAG(can_post_method_exit)
  90   JVMTI_SUPPORT_FLAG(can_pop_frame)
  91   JVMTI_SUPPORT_FLAG(can_force_early_return)
  92 
  93   JVMTI_SUPPORT_FLAG(early_vmstart_recorded)
  94 
  95   friend class JvmtiEventControllerPrivate;  // should only modify these flags
  96   JVMTI_SUPPORT_FLAG(should_post_single_step)
  97   JVMTI_SUPPORT_FLAG(should_post_field_access)
  98   JVMTI_SUPPORT_FLAG(should_post_field_modification)
  99   JVMTI_SUPPORT_FLAG(should_post_class_load)
 100   JVMTI_SUPPORT_FLAG(should_post_class_prepare)
 101   JVMTI_SUPPORT_FLAG(should_post_class_unload)
 102   JVMTI_SUPPORT_FLAG(should_post_native_method_bind)
 103   JVMTI_SUPPORT_FLAG(should_post_compiled_method_load)
 104   JVMTI_SUPPORT_FLAG(should_post_compiled_method_unload)
 105   JVMTI_SUPPORT_FLAG(should_post_dynamic_code_generated)
 106   JVMTI_SUPPORT_FLAG(should_post_monitor_contended_enter)
 107   JVMTI_SUPPORT_FLAG(should_post_monitor_contended_entered)
 108   JVMTI_SUPPORT_FLAG(should_post_monitor_wait)
 109   JVMTI_SUPPORT_FLAG(should_post_monitor_waited)
 110   JVMTI_SUPPORT_FLAG(should_post_data_dump)
 111   JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start)
 112   JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish)
 113   JVMTI_SUPPORT_FLAG(should_post_on_exceptions)
 114 
 115   // ------ the below maybe don't have to be (but are for now)
 116   // fixed conditions here ------------
 117   // any events can be enabled
 118   JVMTI_SUPPORT_FLAG(should_post_thread_life)
 119   JVMTI_SUPPORT_FLAG(should_post_object_free)
 120   JVMTI_SUPPORT_FLAG(should_post_resource_exhausted)
 121 
 122   // we are holding objects on the heap - need to talk to GC - e.g.
 123   // breakpoint info
 124   JVMTI_SUPPORT_FLAG(should_clean_up_heap_objects)
 125   JVMTI_SUPPORT_FLAG(should_post_vm_object_alloc)
 126   JVMTI_SUPPORT_FLAG(should_post_sampled_object_alloc)
 127 
 128   // If flag cannot be implemented, give an error if on=true
 129   static void report_unsupported(bool on);
 130 
 131   // these should only be called by the friend class
 132   friend class JvmtiManageCapabilities;
 133   inline static void set_can_modify_any_class(bool on) {
 134     JVMTI_ONLY(_can_modify_any_class = (on != 0);)
 135   }
 136   inline static void set_can_access_local_variables(bool on) {
 137     JVMTI_ONLY(_can_access_local_variables = (on != 0);)
 138   }
 139   inline static void set_can_hotswap_or_post_breakpoint(bool on) {
 140     JVMTI_ONLY(_can_hotswap_or_post_breakpoint = (on != 0);)
 141   }
 142   inline static void set_can_walk_any_space(bool on) {
 143     JVMTI_ONLY(_can_walk_any_space = (on != 0);)
 144   }
 145 
 146   enum {
 147     JVMTI_VERSION_MASK   = 0x70000000,
 148     JVMTI_VERSION_VALUE  = 0x30000000,
 149     JVMDI_VERSION_VALUE  = 0x20000000
 150   };
 151 
 152   static void post_field_modification(JavaThread *thread, Method* method, address location,
 153                                       Klass* field_klass, Handle object, jfieldID field,
 154                                       char sig_type, jvalue *value);
 155 
 156 
 157   // posts a DynamicCodeGenerated event (internal/private implementation).
 158   // The public post_dynamic_code_generated* functions make use of the
 159   // internal implementation.  Also called from JvmtiDeferredEvent::post()
 160   static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
 161 
 162  private:
 163 
 164   // GenerateEvents support to allow posting of CompiledMethodLoad and
 165   // DynamicCodeGenerated events for a given environment.
 166   friend class JvmtiCodeBlobEvents;
 167 
 168   static void post_compiled_method_load(JvmtiEnv* env, nmethod *nm) NOT_JVMTI_RETURN;
 169   static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin,
 170                                           const void *code_end) NOT_JVMTI_RETURN;
 171 
 172   // This flag indicates whether RedefineClasses() has ever redefined
 173   // one or more classes during the lifetime of the VM. The flag should
 174   // only be set by the friend class and can be queried by other sub
 175   // systems as needed to relax invariant checks.
 176   static bool _has_redefined_a_class;
 177   friend class VM_RedefineClasses;
 178   inline static void set_has_redefined_a_class() {
 179     JVMTI_ONLY(_has_redefined_a_class = true;)
 180   }
 181   // Flag to indicate if the compiler has recorded all dependencies. When the
 182   // can_redefine_classes capability is enabled in the OnLoad phase then the compiler
 183   // records all dependencies from startup. However if the capability is first
 184   // enabled some time later then the dependencies recorded by the compiler
 185   // are incomplete. This flag is used by RedefineClasses to know if the
 186   // dependency information is complete or not.
 187   static bool _all_dependencies_are_recorded;
 188 
 189  public:
 190   inline static bool has_redefined_a_class() {
 191     JVMTI_ONLY(return _has_redefined_a_class);
 192     NOT_JVMTI(return false);
 193   }
 194 
 195   inline static bool all_dependencies_are_recorded() {
 196     return _all_dependencies_are_recorded;
 197   }
 198 
 199   inline static void set_all_dependencies_are_recorded(bool on) {
 200     _all_dependencies_are_recorded = (on != 0);
 201   }
 202 
 203   // Add read edges to the unnamed modules of the bootstrap and app class loaders
 204   static void add_default_read_edges(Handle h_module, TRAPS) NOT_JVMTI_RETURN;
 205 
 206   // Add a read edge to the module
 207   static jvmtiError add_module_reads(Handle module, Handle to_module, TRAPS);
 208 
 209   // Updates a module to export a package
 210   static jvmtiError add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS);
 211 
 212   // Updates a module to open a package
 213   static jvmtiError add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS);
 214 
 215   // Add a used service to the module
 216   static jvmtiError add_module_uses(Handle module, Handle service, TRAPS);
 217 
 218   // Add a service provider to the module
 219   static jvmtiError add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS);
 220 
 221   // let JVMTI know that the JVM_OnLoad code is running
 222   static void enter_onload_phase() NOT_JVMTI_RETURN;
 223 
 224   // let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running)
 225   static void enter_primordial_phase() NOT_JVMTI_RETURN;
 226 
 227   // let JVMTI know that the VM isn't up yet but JNI is live
 228   static void enter_early_start_phase() NOT_JVMTI_RETURN;
 229   static void enter_start_phase() NOT_JVMTI_RETURN;
 230 
 231   // let JVMTI know that the VM is fully up and running now
 232   static void enter_live_phase() NOT_JVMTI_RETURN;
 233 
 234   // ------ can_* conditions (below) are set at OnLoad and never changed ------------
 235   inline static bool can_modify_any_class()                       {
 236     JVMTI_ONLY(return _can_modify_any_class);
 237     NOT_JVMTI(return false);
 238   }
 239   inline static bool can_access_local_variables()                 {
 240     JVMTI_ONLY(return _can_access_local_variables);
 241     NOT_JVMTI(return false);
 242   }
 243   inline static bool can_hotswap_or_post_breakpoint()             {
 244     JVMTI_ONLY(return _can_hotswap_or_post_breakpoint);
 245     NOT_JVMTI(return false);
 246   }
 247   inline static bool can_walk_any_space()                         {
 248     JVMTI_ONLY(return _can_walk_any_space);
 249     NOT_JVMTI(return false);
 250   }
 251 
 252   // field access management
 253   static address  get_field_access_count_addr() NOT_JVMTI_RETURN_(0);
 254 
 255   // field modification management
 256   static address  get_field_modification_count_addr() NOT_JVMTI_RETURN_(0);
 257 
 258   // -----------------
 259 
 260   static bool is_jvmti_version(jint version)                      {
 261     JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE);
 262     NOT_JVMTI(return false);
 263   }
 264   static bool is_jvmdi_version(jint version)                      {
 265     JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE);
 266     NOT_JVMTI(return false);
 267   }
 268   static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version) NOT_JVMTI_RETURN_(0);
 269   static void decode_version_values(jint version, int * major, int * minor,
 270                                     int * micro) NOT_JVMTI_RETURN;
 271 
 272   // single stepping management methods
 273   static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
 274   static void expose_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN;
 275   static bool hide_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN_(false);
 276 
 277   // Methods that notify the debugger that something interesting has happened in the VM.
 278   static void post_early_vm_start        () NOT_JVMTI_RETURN;
 279   static void post_vm_start              () NOT_JVMTI_RETURN;
 280   static void post_vm_initialized        () NOT_JVMTI_RETURN;
 281   static void post_vm_death              () NOT_JVMTI_RETURN;
 282 
 283   static void post_single_step           (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
 284   static void post_raw_breakpoint        (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
 285 
 286   static void post_exception_throw       (JavaThread *thread, Method* method, address location, oop exception) NOT_JVMTI_RETURN;
 287   static void notice_unwind_due_to_exception (JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) NOT_JVMTI_RETURN;
 288 
 289   static oop jni_GetField_probe          (JavaThread *thread, jobject jobj,
 290     oop obj, Klass* klass, jfieldID fieldID, bool is_static)
 291     NOT_JVMTI_RETURN_(NULL);
 292   static oop jni_GetField_probe_nh       (JavaThread *thread, jobject jobj,
 293     oop obj, Klass* klass, jfieldID fieldID, bool is_static)
 294     NOT_JVMTI_RETURN_(NULL);
 295   static void post_field_access_by_jni   (JavaThread *thread, oop obj,
 296     Klass* klass, jfieldID fieldID, bool is_static) NOT_JVMTI_RETURN;
 297   static void post_field_access          (JavaThread *thread, Method* method,
 298     address location, Klass* field_klass, Handle object, jfieldID field) NOT_JVMTI_RETURN;
 299   static oop jni_SetField_probe          (JavaThread *thread, jobject jobj,
 300     oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
 301     jvalue *value) NOT_JVMTI_RETURN_(NULL);
 302   static oop jni_SetField_probe_nh       (JavaThread *thread, jobject jobj,
 303     oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
 304     jvalue *value) NOT_JVMTI_RETURN_(NULL);
 305   static void post_field_modification_by_jni(JavaThread *thread, oop obj,
 306     Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
 307     jvalue *value);
 308   static void post_raw_field_modification(JavaThread *thread, Method* method,
 309     address location, Klass* field_klass, Handle object, jfieldID field,
 310     char sig_type, jvalue *value) NOT_JVMTI_RETURN;
 311 
 312   static void post_method_entry          (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
 313   static void post_method_exit           (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
 314 
 315   static void post_class_load            (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
 316   static void post_class_unload          (Klass* klass) NOT_JVMTI_RETURN;
 317   static void post_class_prepare         (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
 318 
 319   static void post_thread_start          (JavaThread *thread) NOT_JVMTI_RETURN;
 320   static void post_thread_end            (JavaThread *thread) NOT_JVMTI_RETURN;
 321 
 322   // Support for java.lang.instrument agent loading.
 323   static bool _should_post_class_file_load_hook;
 324   inline static void set_should_post_class_file_load_hook(bool on)     { _should_post_class_file_load_hook = on;  }
 325   inline static bool should_post_class_file_load_hook()           {
 326     JVMTI_ONLY(return _should_post_class_file_load_hook);
 327     NOT_JVMTI(return false;)
 328   }
 329   static bool is_early_phase() NOT_JVMTI_RETURN_(false);
 330   static bool has_early_class_hook_env() NOT_JVMTI_RETURN_(false);
 331   // Return true if the class was modified by the hook.
 332   static bool post_class_file_load_hook(Symbol* h_name, Handle class_loader,
 333                                         Handle h_protection_domain,
 334                                         unsigned char **data_ptr, unsigned char **end_ptr,
 335                                         JvmtiCachedClassFileData **cache_ptr) NOT_JVMTI_RETURN_(false);
 336   static void post_native_method_bind(Method* method, address* function_ptr) NOT_JVMTI_RETURN;
 337   static void post_compiled_method_load(nmethod *nm) NOT_JVMTI_RETURN;
 338   static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
 339 
 340   // used to post a CompiledMethodUnload event
 341   static void post_compiled_method_unload(jmethodID mid, const void *code_begin) NOT_JVMTI_RETURN;
 342 
 343   // similiar to post_dynamic_code_generated except that it can be used to
 344   // post a DynamicCodeGenerated event while holding locks in the VM. Any event
 345   // posted using this function is recorded by the enclosing event collector
 346   // -- JvmtiDynamicCodeEventCollector.
 347   static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) NOT_JVMTI_RETURN;
 348 
 349   static void post_garbage_collection_finish() NOT_JVMTI_RETURN;
 350   static void post_garbage_collection_start() NOT_JVMTI_RETURN;
 351   static void post_data_dump() NOT_JVMTI_RETURN;
 352   static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
 353   static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
 354   static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) NOT_JVMTI_RETURN;
 355   static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN;
 356   static void post_object_free(JvmtiEnv* env, jlong tag) NOT_JVMTI_RETURN;
 357   static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) NOT_JVMTI_RETURN;
 358   static void record_vm_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
 359   // Post objects collected by vm_object_alloc_event_collector.
 360   static void post_vm_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
 361   // Collects vm internal objects for later event posting.
 362   inline static void vm_object_alloc_event_collector(oop object) {
 363     if (should_post_vm_object_alloc()) {
 364       record_vm_internal_object_allocation(object);
 365     }
 366   }
 367 
 368   static void record_sampled_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
 369   // Post objects collected by sampled_object_alloc_event_collector.
 370   static void post_sampled_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
 371 
 372   // Collects vm internal objects for later event posting.
 373   inline static void sampled_object_alloc_event_collector(oop object) {
 374     if (should_post_sampled_object_alloc()) {
 375       record_sampled_internal_object_allocation(object);
 376     }
 377   }
 378 
 379   inline static void post_array_size_exhausted() {
 380     if (should_post_resource_exhausted()) {
 381       post_resource_exhausted(JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
 382                               "Requested array size exceeds VM limit");
 383     }
 384   }
 385 
 386   static void cleanup_thread             (JavaThread* thread) NOT_JVMTI_RETURN;
 387   static void clear_detected_exception   (JavaThread* thread) NOT_JVMTI_RETURN;
 388 
 389   static void oops_do(OopClosure* f) NOT_JVMTI_RETURN;
 390   static void weak_oops_do(BoolObjectClosure* b, OopClosure* f) NOT_JVMTI_RETURN;
 391   static void gc_epilogue() NOT_JVMTI_RETURN;
 392 
 393   static void transition_pending_onload_raw_monitors() NOT_JVMTI_RETURN;
 394 
 395 #if INCLUDE_SERVICES
 396   // attach support
 397   static jint load_agent_library(const char *agent, const char *absParam, const char *options, outputStream* out) NOT_JVMTI_RETURN_(JNI_ERR);
 398 #endif
 399 
 400   // SetNativeMethodPrefix support
 401   static char** get_all_native_method_prefixes(int* count_ptr) NOT_JVMTI_RETURN_(NULL);
 402 
 403   // JavaThread lifecycle support:
 404   static jvmtiError cv_external_thread_to_JavaThread(ThreadsList * t_list,
 405                                                      jthread thread,
 406                                                      JavaThread ** jt_pp,
 407                                                      oop * thread_oop_p);
 408   static jvmtiError cv_oop_to_JavaThread(ThreadsList * t_list, oop thread_oop,
 409                                          JavaThread ** jt_pp);
 410 };
 411 
 412 // Support class used by JvmtiDynamicCodeEventCollector and others. It
 413 // describes a single code blob by name and address range.
 414 class JvmtiCodeBlobDesc : public CHeapObj<mtInternal> {
 415  private:
 416   char _name[64];
 417   address _code_begin;
 418   address _code_end;
 419 
 420  public:
 421   JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) {
 422     assert(name != NULL, "all code blobs must be named");
 423     strncpy(_name, name, sizeof(_name) - 1);
 424     _name[sizeof(_name)-1] = '\0';
 425     _code_begin = code_begin;
 426     _code_end = code_end;
 427   }
 428   char* name()                  { return _name; }
 429   address code_begin()          { return _code_begin; }
 430   address code_end()            { return _code_end; }
 431 };
 432 
 433 // JvmtiEventCollector is a helper class to setup thread for
 434 // event collection.
 435 class JvmtiEventCollector : public StackObj {
 436  private:
 437   JvmtiEventCollector* _prev;  // Save previous one to support nested event collector.
 438   bool _unset_jvmti_thread_state;
 439 
 440  public:
 441   JvmtiEventCollector() : _prev(NULL), _unset_jvmti_thread_state(false) {}
 442 
 443   void setup_jvmti_thread_state(); // Set this collector in current thread, returns if success.
 444   void unset_jvmti_thread_state(); // Reset previous collector in current thread.
 445   virtual bool is_dynamic_code_event()   { return false; }
 446   virtual bool is_vm_object_alloc_event(){ return false; }
 447   virtual bool is_sampled_object_alloc_event(){ return false; }
 448   JvmtiEventCollector *get_prev()        { return _prev; }
 449 };
 450 
 451 // A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport
 452 // interface. It collects "dynamic code generated" events that are posted
 453 // while holding locks. When the event collector goes out of scope the
 454 // events will be posted.
 455 //
 456 // Usage :-
 457 //
 458 // {
 459 //   JvmtiDynamicCodeEventCollector event_collector;
 460 //   :
 461 //   { MutexLocker ml(...)
 462 //     :
 463 //     JvmtiExport::post_dynamic_code_generated_while_holding_locks(...)
 464 //   }
 465 //   // event collector goes out of scope => post events to profiler.
 466 // }
 467 
 468 class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector {
 469  private:
 470   GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs;           // collected code blob events
 471 
 472   friend class JvmtiExport;
 473   void register_stub(const char* name, address start, address end);
 474 
 475  public:
 476   JvmtiDynamicCodeEventCollector()  NOT_JVMTI_RETURN;
 477   ~JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
 478   bool is_dynamic_code_event()   { return true; }
 479 
 480 };
 481 
 482 // Used as a base class for object allocation collection and then posting
 483 // the allocations to any event notification callbacks.
 484 //
 485 class JvmtiObjectAllocEventCollector : public JvmtiEventCollector {
 486  protected:
 487   GrowableArray<oop>* _allocated;      // field to record collected allocated object oop.
 488   bool _enable;                   // This flag is enabled in constructor if set up in the thread state
 489                                   // and disabled in destructor before posting event. To avoid
 490                                   // collection of objects allocated while running java code inside
 491                                   // agent post_X_object_alloc() event handler.
 492   void (*_post_callback)(JavaThread*, oop); // what callback to use when destroying the collector.
 493 
 494   //GC support
 495   void oops_do(OopClosure* f);
 496 
 497   friend class JvmtiExport;
 498 
 499   // Record allocated object oop.
 500   inline void record_allocation(oop obj);
 501 
 502   //GC support
 503   static void oops_do_for_all_threads(OopClosure* f);
 504 
 505  public:
 506   JvmtiObjectAllocEventCollector()  NOT_JVMTI_RETURN;
 507 
 508   void generate_call_for_allocated();
 509 
 510   bool is_enabled()                 { return _enable; }
 511   void set_enabled(bool on)         { _enable = on; }
 512 };
 513 
 514 // Used to record vm internally allocated object oops and post
 515 // vm object alloc event for objects visible to java world.
 516 // Constructor enables JvmtiThreadState flag and all vm allocated
 517 // objects are recorded in a growable array. When destructor is
 518 // called the vm object alloc event is posted for each object
 519 // visible to java world.
 520 // See jvm.cpp file for its usage.
 521 //
 522 class JvmtiVMObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
 523  public:
 524   JvmtiVMObjectAllocEventCollector()  NOT_JVMTI_RETURN;
 525   ~JvmtiVMObjectAllocEventCollector()  NOT_JVMTI_RETURN;
 526   virtual bool is_vm_object_alloc_event()   { return true; }
 527 };
 528 
 529 // Used to record sampled allocated object oops and post
 530 // sampled object alloc event.
 531 // Constructor enables JvmtiThreadState flag and all sampled allocated
 532 // objects are recorded in a growable array. When destructor is
 533 // called the sampled object alloc event is posted for each sampled object.
 534 // See jvm.cpp file for its usage.
 535 //
 536 class JvmtiSampledObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
 537  public:
 538   JvmtiSampledObjectAllocEventCollector()  NOT_JVMTI_RETURN;
 539   ~JvmtiSampledObjectAllocEventCollector()  NOT_JVMTI_RETURN;
 540   bool is_sampled_object_alloc_event()    { return true; }
 541   static bool object_alloc_is_safe_to_sample() NOT_JVMTI_RETURN_(false);
 542 };
 543 
 544 // Marker class to disable the posting of VMObjectAlloc events
 545 // within its scope.
 546 //
 547 // Usage :-
 548 //
 549 // {
 550 //   NoJvmtiVMObjectAllocMark njm;
 551 //   :
 552 //   // VMObjAlloc event will not be posted
 553 //   JvmtiExport::vm_object_alloc_event_collector(obj);
 554 //   :
 555 // }
 556 
 557 class NoJvmtiVMObjectAllocMark : public StackObj {
 558  private:
 559   // enclosing collector if enabled, NULL otherwise
 560   JvmtiVMObjectAllocEventCollector *_collector;
 561 
 562   bool was_enabled()    { return _collector != NULL; }
 563 
 564  public:
 565   NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
 566   ~NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
 567 };
 568 
 569 
 570 // Base class for reporting GC events to JVMTI.
 571 class JvmtiGCMarker : public StackObj {
 572  public:
 573   JvmtiGCMarker() NOT_JVMTI_RETURN;
 574   ~JvmtiGCMarker() NOT_JVMTI_RETURN;
 575 };
 576 
 577 // JvmtiHideSingleStepping is a helper class for hiding
 578 // internal single step events.
 579 class JvmtiHideSingleStepping : public StackObj {
 580  private:
 581   bool         _single_step_hidden;
 582   JavaThread * _thread;
 583 
 584  public:
 585   JvmtiHideSingleStepping(JavaThread * thread) {
 586     assert(thread != NULL, "sanity check");
 587 
 588     _single_step_hidden = false;
 589     _thread = thread;
 590     if (JvmtiExport::should_post_single_step()) {
 591       _single_step_hidden = JvmtiExport::hide_single_stepping(_thread);
 592     }
 593   }
 594 
 595   ~JvmtiHideSingleStepping() {
 596     if (_single_step_hidden) {
 597       JvmtiExport::expose_single_stepping(_thread);
 598     }
 599   }
 600 };
 601 
 602 #endif // SHARE_PRIMS_JVMTIEXPORT_HPP