src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.

@@ -157,10 +157,107 @@
   bool adaptive_young_list_length() {
     return _adaptive_size;
   }
 };
 
+class G1CollectorState VALUE_OBJ_CLASS_SPEC {
+  // Various boolean state variables that indicate
+  // the phase of the G1 collection.
+  bool _in_young_gc_mode;
+  // indicates whether we are in full young or partially young GC mode
+  bool _gcs_are_young;
+  bool _last_gc_was_young;
+  bool _last_young_gc;
+  
+  // If initiate_conc_mark_if_possible() is set at the beginning of a
+  // pause, it is a suggestion that the pause should start a marking
+  // cycle by doing the initial-mark work. However, it is possible
+  // that the concurrent marking thread is still finishing up the
+  // previous marking cycle (e.g., clearing the next marking
+  // bitmap). If that is the case we cannot start a new cycle and
+  // we'll have to wait for the concurrent marking thread to finish
+  // what it is doing. In this case we will postpone the marking cycle
+  // initiation decision for the next pause. When we eventually decide
+  // to start a cycle, we will set _during_initial_mark_pause which
+  // will stay true until the end of the initial-mark pause and it's
+  // the condition that indicates that a pause is doing the
+  // initial-mark work.
+  volatile bool _during_initial_mark_pause;
+ 
+  // At the end of a pause we check the heap occupancy and we decide
+  // whether we will start a marking cycle during the next pause. If
+  // we decide that we want to do that, we will set this parameter to
+  // true. So, this parameter will stay true between the end of a
+  // pause and the beginning of a subsequent pause (not necessarily
+  // the next one, see the comments on the next field) when we decide
+  // that we will indeed start a marking cycle and do the initial-mark
+  // work.
+  volatile bool _initiate_conc_mark_if_possible;
+ 
+  // NOTE: if some of these are synonyms for others,
+  // the redundant fields should be eliminated. XXX
+  bool _during_marking;
+  bool _mark_in_progress;
+  bool _in_marking_window;
+  bool _in_marking_window_im;
+ 
+  public:
+    G1CollectorState() :
+      _in_young_gc_mode(false),
+      _gcs_are_young(true),
+      _last_gc_was_young(false),
+      _last_young_gc(false),
+
+      _during_initial_mark_pause(false),
+      _initiate_conc_mark_if_possible(false),
+
+      _during_marking(false),
+      _mark_in_progress(false),
+      _in_marking_window(false),
+      _in_marking_window_im(false) {}
+  
+ 
+  // Setters
+  void set_in_young_gc_mode(bool v) { _in_young_gc_mode = v; }
+  void set_gcs_are_young(bool v) { _gcs_are_young = v; }
+  void set_last_gc_was_young(bool v) { _last_gc_was_young = v; }
+  void set_last_young_gc(bool v) { _last_young_gc = v; }
+  void set_during_initial_mark_pause(bool v) { _during_initial_mark_pause = v; }
+  void set_initiate_conc_mark_if_possible(bool v) { _initiate_conc_mark_if_possible = v; }
+  void set_during_marking(bool v) { _during_marking = v; }
+  void set_mark_in_progress(bool v) { _mark_in_progress = v; }
+  void set_in_marking_window(bool v) { _in_marking_window = v; }
+  void set_in_marking_window_im(bool v) { _in_marking_window_im = v; }
+ 
+  // Puns
+  ////////
+  void set_marking_complete() { set_mark_in_progress(false); }
+  void set_marking_started() { set_mark_in_progress(true); }
+ 
+  // Getters
+  bool in_young_gc_mode() { return _in_young_gc_mode; }
+  bool gcs_are_young() { return _gcs_are_young; }
+  bool last_gc_was_young() { return _last_gc_was_young; }
+  bool last_young_gc() { return _last_young_gc; }
+  bool during_initial_mark_pause() { return _during_initial_mark_pause; }
+  bool initiate_conc_mark_if_possible() { return _initiate_conc_mark_if_possible; }
+  bool during_marking() { return _during_marking; }
+  bool mark_in_progress() { return _mark_in_progress; }
+  bool in_marking_window() { return _in_marking_window; }
+  bool in_marking_window_im() { return _in_marking_window_im; }
+ 
+ 
+  // Composite booleans (clients worry about flickering)
+  bool during_concurrent_mark() {
+    return (_in_marking_window && !_in_marking_window_im);
+  }
+ 
+  bool should_propagate() { // XXX should have a more suitable state name or abstraction for this
+    return (_last_young_gc && !_in_marking_window);
+  }
+};
+
 class G1CollectorPolicy: public CollectorPolicy {
 private:
   // either equal to the number of parallel threads, if ParallelGCThreads
   // has been set, or 1 otherwise
   int _parallel_gc_threads;

@@ -192,38 +289,28 @@
   TraceOldGenTimeData   _trace_old_gen_time_data;
 
   double _stop_world_start;
 
   // indicates whether we are in young or mixed GC mode
-  bool _gcs_are_young;
+  G1CollectorState _collector_state;
 
   uint _young_list_target_length;
   uint _young_list_fixed_length;
 
   // The max number of regions we can extend the eden by while the GC
   // locker is active. This should be >= _young_list_target_length;
   uint _young_list_max_length;
 
-  bool _last_gc_was_young;
-
-  bool _during_marking;
-  bool _in_marking_window;
-  bool _in_marking_window_im;
-
   SurvRateGroup* _short_lived_surv_rate_group;
   SurvRateGroup* _survivor_surv_rate_group;
   // add here any more surv rate groups
 
   double _gc_overhead_perc;
 
   double _reserve_factor;
   uint   _reserve_regions;
 
-  bool during_marking() {
-    return _during_marking;
-  }
-
   enum PredictionConstants {
     TruncatedSeqLength = 10
   };
 
   TruncatedSeq* _alloc_rate_ms_seq;

@@ -361,11 +448,11 @@
     return (size_t) ((double) rs_length *
                      predict_mixed_cards_per_entry_ratio());
   }
 
   double predict_rs_scan_time_ms(size_t card_num) {
-    if (gcs_are_young()) {
+    if (collector_state()->gcs_are_young()) {
       return (double) card_num * get_new_prediction(_cost_per_entry_ms_seq);
     } else {
       return predict_mixed_rs_scan_time_ms(card_num);
     }
   }

@@ -388,11 +475,11 @@
              get_new_prediction(_cost_per_byte_ms_during_cm_seq);
     }
   }
 
   double predict_object_copy_time_ms(size_t bytes_to_copy) {
-    if (_in_marking_window && !_in_marking_window_im) {
+    if (collector_state()->during_concurrent_mark()) {
       return predict_object_copy_time_ms_during_cm(bytes_to_copy);
     } else {
       return (double) bytes_to_copy *
               get_new_prediction(_cost_per_byte_ms_seq);
     }

@@ -426,11 +513,11 @@
                                            survivor_cset_region_length(); }
 
   double predict_survivor_regions_evac_time();
 
   void cset_regions_freed() {
-    bool propagate = _last_gc_was_young && !_in_marking_window;
+    bool propagate = collector_state()->should_propagate();
     _short_lived_surv_rate_group->all_surviving_words_recorded(propagate);
     _survivor_surv_rate_group->all_surviving_words_recorded(propagate);
     // also call it on any more surv rate groups
   }
 

@@ -550,37 +637,10 @@
 
   double recent_avg_pause_time_ratio() {
     return _recent_avg_pause_time_ratio;
   }
 
-  // At the end of a pause we check the heap occupancy and we decide
-  // whether we will start a marking cycle during the next pause. If
-  // we decide that we want to do that, we will set this parameter to
-  // true. So, this parameter will stay true between the end of a
-  // pause and the beginning of a subsequent pause (not necessarily
-  // the next one, see the comments on the next field) when we decide
-  // that we will indeed start a marking cycle and do the initial-mark
-  // work.
-  volatile bool _initiate_conc_mark_if_possible;
-
-  // If initiate_conc_mark_if_possible() is set at the beginning of a
-  // pause, it is a suggestion that the pause should start a marking
-  // cycle by doing the initial-mark work. However, it is possible
-  // that the concurrent marking thread is still finishing up the
-  // previous marking cycle (e.g., clearing the next marking
-  // bitmap). If that is the case we cannot start a new cycle and
-  // we'll have to wait for the concurrent marking thread to finish
-  // what it is doing. In this case we will postpone the marking cycle
-  // initiation decision for the next pause. When we eventually decide
-  // to start a cycle, we will set _during_initial_mark_pause which
-  // will stay true until the end of the initial-mark pause and it's
-  // the condition that indicates that a pause is doing the
-  // initial-mark work.
-  volatile bool _during_initial_mark_pause;
-
-  bool _last_young_gc;
-
   // This set of variables tracks the collector efficiency, in order to
   // determine whether we should initiate a new marking.
   double _cur_mark_stop_world_time_ms;
   double _mark_remark_start_sec;
   double _mark_cleanup_start_sec;

@@ -645,10 +705,12 @@
 
   virtual CollectorPolicy::Name kind() {
     return CollectorPolicy::G1CollectorPolicyKind;
   }
 
+  G1CollectorState* collector_state() { return &_collector_state; }
+  
   G1GCPhaseTimes* phase_times() const { return _phase_times; }
 
   // Check the current value of the young list RSet lengths and
   // compare it against the last prediction. If the current value is
   // higher, recalculate the young list target length prediction.

@@ -782,18 +844,10 @@
 
 #ifndef PRODUCT
   void print_collection_set(HeapRegion* list_head, outputStream* st);
 #endif // !PRODUCT
 
-  bool initiate_conc_mark_if_possible()       { return _initiate_conc_mark_if_possible;  }
-  void set_initiate_conc_mark_if_possible()   { _initiate_conc_mark_if_possible = true;  }
-  void clear_initiate_conc_mark_if_possible() { _initiate_conc_mark_if_possible = false; }
-
-  bool during_initial_mark_pause()      { return _during_initial_mark_pause;  }
-  void set_during_initial_mark_pause()  { _during_initial_mark_pause = true;  }
-  void clear_during_initial_mark_pause(){ _during_initial_mark_pause = false; }
-
   // This sets the initiate_conc_mark_if_possible() flag to start a
   // new cycle, as long as we are not already in one. It's best if it
   // is called during a safepoint when the test whether a cycle is in
   // progress or not is stable.
   bool force_initial_mark_if_outside_cycle(GCCause::Cause gc_cause);

@@ -833,17 +887,10 @@
 
   uint young_list_max_length() {
     return _young_list_max_length;
   }
 
-  bool gcs_are_young() {
-    return _gcs_are_young;
-  }
-  void set_gcs_are_young(bool gcs_are_young) {
-    _gcs_are_young = gcs_are_young;
-  }
-
   bool adaptive_young_list_length() {
     return _young_gen_sizer->adaptive_young_list_length();
   }
 
 private: