1 /*
   2  * Copyright (c) 2003, 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_SERVICES_MEMORYMANAGER_HPP
  26 #define SHARE_VM_SERVICES_MEMORYMANAGER_HPP
  27 
  28 #include "gc/shared/gcCause.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "oops/oopsHierarchy.hpp"
  31 #include "runtime/handles.hpp"
  32 #include "runtime/timer.hpp"
  33 #include "services/memoryUsage.hpp"
  34 
  35 // A memory manager is responsible for managing one or more memory pools.
  36 // The garbage collector is one type of memory managers responsible
  37 // for reclaiming memory occupied by unreachable objects.  A Java virtual
  38 // machine may have one or more memory managers.   It may
  39 // add or remove memory managers during execution.
  40 // A memory pool can be managed by more than one memory managers.
  41 
  42 class MemoryPool;
  43 class GCMemoryManager;
  44 class OopClosure;
  45 
  46 class MemoryManager : public CHeapObj<mtInternal> {
  47 protected:
  48   enum {
  49     max_num_pools = 10
  50   };
  51 
  52 private:
  53   MemoryPool* _pools[max_num_pools];
  54   int         _num_pools;
  55 
  56   const char* _name;
  57 
  58 protected:
  59   volatile instanceOop _memory_mgr_obj;
  60 
  61 public:
  62   MemoryManager(const char* name);
  63 
  64   int num_memory_pools() const           { return _num_pools; }
  65   MemoryPool* get_memory_pool(int index) {
  66     assert(index >= 0 && index < _num_pools, "Invalid index");
  67     return _pools[index];
  68   }
  69 
  70   int add_pool(MemoryPool* pool);
  71 
  72   bool is_manager(instanceHandle mh)     { return mh() == _memory_mgr_obj; }
  73 
  74   virtual instanceOop get_memory_manager_instance(TRAPS);
  75   virtual bool is_gc_memory_manager()    { return false; }
  76 
  77   const char* name() const { return _name; }
  78 
  79   // GC support
  80   void oops_do(OopClosure* f);
  81 
  82   // Static factory methods to get a memory manager of a specific type
  83   static MemoryManager*   get_code_cache_memory_manager();
  84   static MemoryManager*   get_metaspace_memory_manager();
  85 };
  86 
  87 class GCStatInfo : public ResourceObj {
  88 private:
  89   size_t _index;
  90   jlong  _start_time;
  91   jlong  _end_time;
  92 
  93   // We keep memory usage of all memory pools
  94   MemoryUsage* _before_gc_usage_array;
  95   MemoryUsage* _after_gc_usage_array;
  96   int          _usage_array_size;
  97 
  98   void set_gc_usage(int pool_index, MemoryUsage, bool before_gc);
  99 
 100 public:
 101   GCStatInfo(int num_pools);
 102   ~GCStatInfo();
 103 
 104   size_t gc_index()               { return _index; }
 105   jlong  start_time()             { return _start_time; }
 106   jlong  end_time()               { return _end_time; }
 107   int    usage_array_size()       { return _usage_array_size; }
 108   MemoryUsage before_gc_usage_for_pool(int pool_index) {
 109     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 110     return _before_gc_usage_array[pool_index];
 111   }
 112   MemoryUsage after_gc_usage_for_pool(int pool_index) {
 113     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 114     return _after_gc_usage_array[pool_index];
 115   }
 116 
 117   MemoryUsage* before_gc_usage_array() { return _before_gc_usage_array; }
 118   MemoryUsage* after_gc_usage_array()  { return _after_gc_usage_array; }
 119 
 120   void set_index(size_t index)    { _index = index; }
 121   void set_start_time(jlong time) { _start_time = time; }
 122   void set_end_time(jlong time)   { _end_time = time; }
 123   void set_before_gc_usage(int pool_index, MemoryUsage usage) {
 124     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 125     set_gc_usage(pool_index, usage, true /* before gc */);
 126   }
 127   void set_after_gc_usage(int pool_index, MemoryUsage usage) {
 128     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 129     set_gc_usage(pool_index, usage, false /* after gc */);
 130   }
 131 
 132   void clear();
 133 };
 134 
 135 class GCMemoryManager : public MemoryManager {
 136 private:
 137   // TODO: We should unify the GCCounter and GCMemoryManager statistic
 138   size_t       _num_collections;
 139   elapsedTimer _accumulated_timer;
 140   elapsedTimer _gc_timer;         // for measuring every GC duration
 141   GCStatInfo*  _last_gc_stat;
 142   Mutex*       _last_gc_lock;
 143   GCStatInfo*  _current_gc_stat;
 144   int          _num_gc_threads;
 145   volatile bool _notification_enabled;
 146   const char* _gc_end_message;
 147   bool        _pool_always_affected_by_gc[MemoryManager::max_num_pools];
 148 
 149 public:
 150   GCMemoryManager(const char* name, const char* gc_end_message);
 151   ~GCMemoryManager();
 152 
 153   int add_pool(MemoryPool* pool, bool always_affected_by_gc = true);
 154   bool pool_always_affected_by_gc(int index) {
 155     assert(index >= 0 && index < num_memory_pools(), "Invalid index");
 156     return _pool_always_affected_by_gc[index];
 157   }
 158 
 159 void   initialize_gc_stat_info();
 160 
 161   bool   is_gc_memory_manager()         { return true; }
 162   jlong  gc_time_ms()                   { return _accumulated_timer.milliseconds(); }
 163   size_t gc_count()                     { return _num_collections; }
 164   int    num_gc_threads()               { return _num_gc_threads; }
 165   void   set_num_gc_threads(int count)  { _num_gc_threads = count; }
 166 
 167   void   gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 168                   bool recordAccumulatedGCTime);
 169   void   gc_end(bool recordPostGCUsage, bool recordAccumulatedGCTime,
 170                 bool recordGCEndTime, bool countCollection, GCCause::Cause cause,
 171                 bool allMemoryPoolsAffected);
 172 
 173   void        reset_gc_stat()   { _num_collections = 0; _accumulated_timer.reset(); }
 174 
 175   // Copy out _last_gc_stat to the given destination, returning
 176   // the collection count. Zero signifies no gc has taken place.
 177   size_t get_last_gc_stat(GCStatInfo* dest);
 178 
 179   void set_notification_enabled(bool enabled) { _notification_enabled = enabled; }
 180   bool is_notification_enabled() { return _notification_enabled; }
 181 };
 182 
 183 #endif // SHARE_VM_SERVICES_MEMORYMANAGER_HPP