1 /*
  2  * Copyright (c) 2003, 2023, 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.
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 23  */
 24 
 25 // JvmtiTagMap
 26 
 27 #ifndef SHARE_PRIMS_JVMTITAGMAP_HPP
 28 #define SHARE_PRIMS_JVMTITAGMAP_HPP
 29 
 30 #include "jvmtifiles/jvmti.h"
 31 #include "memory/allocation.hpp"
 32 
 33 class JvmtiEnv;
 34 class JvmtiTagMapTable;
 35 class JvmtiTagMapKeyClosure;
 36 
 37 class JvmtiTagMap :  public CHeapObj<mtServiceability> {
 38  private:
 39 
 40   JvmtiEnv*             _env;                       // the jvmti environment
 41   Monitor               _lock;                      // lock for this tag map
 42   JvmtiTagMapTable*     _hashmap;                   // the hashmap for tags
 43   bool                  _needs_cleaning;
 44   bool                  _posting_events;
 45 
 46   static bool           _has_object_free_events;
 47 
 48   // create a tag map
 49   JvmtiTagMap(JvmtiEnv* env);
 50 
 51   // accessors
 52   inline JvmtiEnv* env() const              { return _env; }
 53 
 54   void entry_iterate(JvmtiTagMapKeyClosure* closure);
 55 
 56  public:
 57   // indicates if this tag map is locked
 58   bool is_locked()                          { return lock()->is_locked(); }
 59   inline Monitor* lock()                    { return &_lock; }
 60 
 61   JvmtiTagMapTable* hashmap() { return _hashmap; }
 62 
 63   // returns true if the hashmaps are empty
 64   bool is_empty();
 65 
 66   // return tag for the given environment
 67   static JvmtiTagMap* tag_map_for(JvmtiEnv* env);
 68 
 69   // destroy tag map
 70   ~JvmtiTagMap();
 71 
 72   // set/get tag
 73   void set_tag(jobject obj, jlong tag);
 74   jlong get_tag(jobject obj);
 75 
 76   // deprecated heap iteration functions
 77   void iterate_over_heap(jvmtiHeapObjectFilter object_filter,
 78                          Klass* klass,
 79                          jvmtiHeapObjectCallback heap_object_callback,
 80                          const void* user_data);
 81 
 82   void iterate_over_reachable_objects(jvmtiHeapRootCallback heap_root_callback,
 83                                       jvmtiStackReferenceCallback stack_ref_callback,
 84                                       jvmtiObjectReferenceCallback object_ref_callback,
 85                                       const void* user_data);
 86 
 87   void iterate_over_objects_reachable_from_object(jobject object,
 88                                                   jvmtiObjectReferenceCallback object_reference_callback,
 89                                                   const void* user_data);
 90 
 91 
 92   // advanced (JVMTI 1.1) heap iteration functions
 93   void iterate_through_heap(jint heap_filter,
 94                             Klass* klass,
 95                             const jvmtiHeapCallbacks* callbacks,
 96                             const void* user_data);
 97 
 98   void follow_references(jint heap_filter,
 99                          Klass* klass,
100                          jobject initial_object,
101                          const jvmtiHeapCallbacks* callbacks,
102                          const void* user_data);
103 
104   // get tagged objects
105   jvmtiError get_objects_with_tags(const jlong* tags, jint count,
106                                    jint* count_ptr, jobject** object_result_ptr,
107                                    jlong** tag_result_ptr);
108 
109   void remove_and_post_dead_objects();
110   void remove_dead_entries(GrowableArray<jlong>* objects);
111   void remove_dead_entries_locked(GrowableArray<jlong>* objects);
112   void post_dead_objects(GrowableArray<jlong>* const objects);
113 
114   static void check_hashmaps_for_heapwalk(GrowableArray<jlong>* objects);
115   static void set_needs_cleaning() NOT_JVMTI_RETURN;
116   static void gc_notification(size_t num_dead_entries) NOT_JVMTI_RETURN;
117 
118   void flush_object_free_events();
119   void clear();  // Clear tagmap table after the env is disposed.
120 
121   // For ServiceThread
122   static void flush_all_object_free_events() NOT_JVMTI_RETURN;
123   static bool has_object_free_events_and_reset() NOT_JVMTI_RETURN_(false);
124 };
125 
126 #endif // SHARE_PRIMS_JVMTITAGMAP_HPP