rev 4773 : 8005849: JEP 167: Event-Based JVM Tracing
Reviewed-by: acorn, coleenp, sla
Contributed-by: Karen Kinnear <karen.kinnear@oracle.com>, Bengt Rutisson <bengt.rutisson@oracle.com>, Calvin Cheung <calvin.cheung@oracle.com>, Erik Gahlin <erik.gahlin@oracle.com>, Erik Helin <erik.helin@oracle.com>, Jesper Wilhelmsson <jesper.wilhelmsson@oracle.com>, Keith McGuigan <keith.mcguigan@oracle.com>, Mattias Tobiasson <mattias.tobiasson@oracle.com>, Markus Gronlund <markus.gronlund@oracle.com>, Mikael Auno <mikael.auno@oracle.com>, Nils Eliasson <nils.eliasson@oracle.com>, Nils Loodin <nils.loodin@oracle.com>, Rickard Backman <rickard.backman@oracle.com>, Staffan Larsen <staffan.larsen@oracle.com>, Stefan Karlsson <stefan.karlsson@oracle.com>, Yekaterina Kantserova <yekaterina.kantserova@oracle.com>

   1 /*
   2  * Copyright (c) 2002, 2012, 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_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP
  27 
  28 #include "gc_implementation/parallelScavenge/psPromotionLAB.hpp"


  29 #include "memory/allocation.hpp"
  30 #include "utilities/taskqueue.hpp"
  31 
  32 //
  33 // psPromotionManager is used by a single thread to manage object survival
  34 // during a scavenge. The promotion manager contains thread local data only.
  35 //
  36 // NOTE! Be carefull when allocating the stacks on cheap. If you are going
  37 // to use a promotion manager in more than one thread, the stacks MUST be
  38 // on cheap. This can lead to memory leaks, though, as they are not auto
  39 // deallocated.
  40 //
  41 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate!
  42 //
  43 
  44 // Move to some global location
  45 #define HAS_BEEN_MOVED 0x1501d01d
  46 // End move to some global location
  47 
  48 class MutableSpace;
  49 class PSOldGen;
  50 class ParCompactionManager;
  51 
  52 class PSPromotionManager : public CHeapObj<mtGC> {
  53   friend class PSScavenge;
  54   friend class PSRefProcTaskExecutor;
  55  private:
  56   static PSPromotionManager**         _manager_array;
  57   static OopStarTaskQueueSet*         _stack_array_depth;
  58   static PSOldGen*                    _old_gen;
  59   static MutableSpace*                _young_space;
  60 
  61 #if TASKQUEUE_STATS
  62   size_t                              _masked_pushes;
  63   size_t                              _masked_steals;
  64   size_t                              _arrays_chunked;
  65   size_t                              _array_chunks_processed;
  66 
  67   void print_taskqueue_stats(uint i) const;
  68   void print_local_stats(uint i) const;
  69   static void print_stats();
  70 
  71   void reset_stats();
  72 #endif // TASKQUEUE_STATS
  73 
  74   PSYoungPromotionLAB                 _young_lab;
  75   PSOldPromotionLAB                   _old_lab;
  76   bool                                _young_gen_is_full;
  77   bool                                _old_gen_is_full;
  78 
  79   OopStarTaskQueue                    _claimed_stack_depth;
  80   OverflowTaskQueue<oop, mtGC>        _claimed_stack_breadth;
  81 
  82   bool                                _totally_drain;
  83   uint                                _target_stack_size;
  84 
  85   uint                                _array_chunk_size;
  86   uint                                _min_array_size_for_chunking;
  87 


  88   // Accessors
  89   static PSOldGen* old_gen()         { return _old_gen; }
  90   static MutableSpace* young_space() { return _young_space; }
  91 
  92   inline static PSPromotionManager* manager_array(int index);
  93   template <class T> inline void claim_or_forward_internal_depth(T* p);
  94 
  95   // On the task queues we push reference locations as well as
  96   // partially-scanned arrays (in the latter case, we push an oop to
  97   // the from-space image of the array and the length on the
  98   // from-space image indicates how many entries on the array we still
  99   // need to scan; this is basically how ParNew does partial array
 100   // scanning too). To be able to distinguish between reference
 101   // locations and partially-scanned array oops we simply mask the
 102   // latter oops with 0x01. The next three methods do the masking,
 103   // unmasking, and checking whether the oop is masked or not. Notice
 104   // that the signature of the mask and unmask methods looks a bit
 105   // strange, as they accept and return different types (oop and
 106   // oop*). This is because of the difference in types between what
 107   // the task queue holds (oop*) and oops to partially-scanned arrays
 108   // (oop). We do all the necessary casting in the mask / unmask
 109   // methods to avoid sprinkling the rest of the code with more casts.
 110 
 111   // These are added to the taskqueue so PS_CHUNKED_ARRAY_OOP_MASK (or any
 112   // future masks) can't conflict with COMPRESSED_OOP_MASK
 113 #define PS_CHUNKED_ARRAY_OOP_MASK  0x2
 114 
 115   bool is_oop_masked(StarTask p) {
 116     // If something is marked chunked it's always treated like wide oop*
 117     return (((intptr_t)(oop*)p) & PS_CHUNKED_ARRAY_OOP_MASK) ==
 118                                   PS_CHUNKED_ARRAY_OOP_MASK;
 119   }
 120 
 121   oop* mask_chunked_array_oop(oop obj) {
 122     assert(!is_oop_masked((oop*) obj), "invariant");
 123     oop* ret = (oop*) ((uintptr_t)obj | PS_CHUNKED_ARRAY_OOP_MASK);
 124     assert(is_oop_masked(ret), "invariant");
 125     return ret;
 126   }
 127 
 128   oop unmask_chunked_array_oop(StarTask p) {
 129     assert(is_oop_masked(p), "invariant");
 130     assert(!p.is_narrow(), "chunked array oops cannot be narrow");
 131     oop *chunk = (oop*)p;  // cast p to oop (uses conversion operator)
 132     oop ret = oop((oop*)((uintptr_t)chunk & ~PS_CHUNKED_ARRAY_OOP_MASK));
 133     assert(!is_oop_masked((oop*) ret), "invariant");
 134     return ret;
 135   }
 136 
 137   template <class T> void  process_array_chunk_work(oop obj,
 138                                                     int start, int end);
 139   void process_array_chunk(oop old);
 140 
 141   template <class T> void push_depth(T* p) {
 142     claimed_stack_depth()->push(p);
 143   }
 144 
 145  protected:
 146   static OopStarTaskQueueSet* stack_array_depth()   { return _stack_array_depth; }
 147  public:
 148   // Static
 149   static void initialize();
 150 
 151   static void pre_scavenge();
 152   static void post_scavenge();
 153 
 154   static PSPromotionManager* gc_thread_promotion_manager(int index);
 155   static PSPromotionManager* vm_thread_promotion_manager();
 156 
 157   static bool steal_depth(int queue_num, int* seed, StarTask& t) {
 158     return stack_array_depth()->steal(queue_num, seed, t);
 159   }
 160 
 161   PSPromotionManager();
 162 
 163   // Accessors
 164   OopStarTaskQueue* claimed_stack_depth() {
 165     return &_claimed_stack_depth;
 166   }
 167 
 168   bool young_gen_is_full()             { return _young_gen_is_full; }
 169 
 170   bool old_gen_is_full()               { return _old_gen_is_full; }
 171   void set_old_gen_is_full(bool state) { _old_gen_is_full = state; }
 172 
 173   // Promotion methods
 174   template<bool promote_immediately> oop copy_to_survivor_space(oop o);
 175   oop oop_promotion_failed(oop obj, markOop obj_mark);
 176 
 177   void reset();
 178 
 179   void flush_labs();
 180   void drain_stacks(bool totally_drain) {
 181     drain_stacks_depth(totally_drain);
 182   }
 183  public:
 184   void drain_stacks_cond_depth() {
 185     if (claimed_stack_depth()->size() > _target_stack_size) {
 186       drain_stacks_depth(false);
 187     }
 188   }
 189   void drain_stacks_depth(bool totally_drain);
 190 
 191   bool stacks_empty() {
 192     return claimed_stack_depth()->is_empty();
 193   }
 194 
 195   inline void process_popped_location_depth(StarTask p);
 196 
 197   template <class T> inline void claim_or_forward_depth(T* p);
 198 
 199   TASKQUEUE_STATS_ONLY(inline void record_steal(StarTask& p);)
 200 };
 201 
 202 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP
--- EOF ---