1 /*
   2  * Copyright (c) 2001, 2015, 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.
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   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
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  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
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  24 
  25 #ifndef SHARE_VM_GC_G1_G1INITIALMARKTOMIXEDTIMETRACKER_HPP
  26 #define SHARE_VM_GC_G1_G1INITIALMARKTOMIXEDTIMETRACKER_HPP
  27 
  28 #include "utilities/globalDefinitions.hpp"
  29 #include "utilities/debug.hpp"
  30 
  31 // Used to track time from the end of initial mark to the first mixed GC.
  32 // After calling the initial mark/mixed gc notifications, the result can be
  33 // obtained in last_marking_time() once, after which the tracking resets.
  34 // Any pauses recorded by add_pause() will be subtracted from that results.
  35 class G1InitialMarkToMixedTimeTracker VALUE_OBJ_CLASS_SPEC {
  36 private:
  37   bool _active;
  38   double _initial_mark_end_time;
  39   double _mixed_start_time;
  40   double _total_pause_time;
  41 
  42   double wall_time() const {
  43     return _mixed_start_time - _initial_mark_end_time;
  44   }
  45 public:
  46   G1InitialMarkToMixedTimeTracker() { reset(); }
  47 
  48   // Record initial mark pause end, starting the time tracking.
  49   void record_initial_mark_end(double end_time) {
  50     assert(!_active, "Initial mark out of order.");
  51     _initial_mark_end_time = end_time;
  52     _active = true;
  53   }
  54 
  55   // Record the first mixed gc pause start, ending the time tracking.
  56   void record_mixed_gc_start(double start_time) {
  57     if (_active) {
  58       _mixed_start_time = start_time;
  59       _active = false;
  60     }
  61   }
  62 
  63   double last_marking_time() {
  64     assert(has_result(), "Do not have all measurements yet.");
  65     double result = (_mixed_start_time - _initial_mark_end_time) - _total_pause_time;
  66     reset();
  67     return result;
  68   }
  69 
  70   void reset() {
  71     _active = false;
  72     _total_pause_time = 0.0;
  73     _initial_mark_end_time = -1.0;
  74     _mixed_start_time = -1.0;
  75   }
  76 
  77   void add_pause(double time) {
  78     if (_active) {
  79       _total_pause_time += time;
  80     }
  81   }
  82 
  83   // Returns whether we have a result that can be retrieved.
  84   bool has_result() const { return _mixed_start_time > 0.0 && _initial_mark_end_time > 0.0; }
  85 };
  86 
  87 #endif // SHARE_VM_GC_G1_G1INITIALMARKTOMIXEDTIMETRACKER_HPP