Mercurial > hg > graal-compiler
view src/share/vm/gc_implementation/g1/g1MMUTracker.hpp @ 6135:8f37087fc13f
7171890: C1: add Class.isInstance intrinsic
Summary: Class.cast which calls Class.isInstance is heavily used by the new JSR 292 implementation
Reviewed-by: roland
Contributed-by: Krystal Mok <rednaxelafx@gmail.com>
author | roland |
---|---|
date | Tue, 05 Jun 2012 10:15:27 +0200 |
parents | f95d63e2154a |
children | d2a62e0f25eb |
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/* * Copyright (c) 2001, 2010, 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. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP #define SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP #include "memory/allocation.hpp" #include "utilities/debug.hpp" // Keeps track of the GC work and decides when it is OK to do GC work // and for how long so that the MMU invariants are maintained. /***** ALL TIMES ARE IN SECS!!!!!!! *****/ // this is the "interface" class G1MMUTracker: public CHeapObj { protected: double _time_slice; double _max_gc_time; // this is per time slice public: G1MMUTracker(double time_slice, double max_gc_time); virtual void add_pause(double start, double end, bool gc_thread) = 0; virtual double longest_pause(double current_time) = 0; virtual double when_sec(double current_time, double pause_time) = 0; double max_gc_time() { return _max_gc_time; } inline bool now_max_gc(double current_time) { return when_sec(current_time, max_gc_time()) < 0.00001; } inline double when_max_gc_sec(double current_time) { return when_sec(current_time, max_gc_time()); } inline jlong when_max_gc_ms(double current_time) { double when = when_max_gc_sec(current_time); return (jlong) (when * 1000.0); } inline jlong when_ms(double current_time, double pause_time) { double when = when_sec(current_time, pause_time); return (jlong) (when * 1000.0); } }; class G1MMUTrackerQueueElem VALUE_OBJ_CLASS_SPEC { private: double _start_time; double _end_time; public: inline double start_time() { return _start_time; } inline double end_time() { return _end_time; } inline double duration() { return _end_time - _start_time; } G1MMUTrackerQueueElem() { _start_time = 0.0; _end_time = 0.0; } G1MMUTrackerQueueElem(double start_time, double end_time) { _start_time = start_time; _end_time = end_time; } }; // this is an implementation of the MMUTracker using a (fixed-size) queue // that keeps track of all the recent pause times class G1MMUTrackerQueue: public G1MMUTracker { private: enum PrivateConstants { QueueLength = 64 }; // The array keeps track of all the pauses that fall within a time // slice (the last time slice during which pauses took place). // The data structure implemented is a circular queue. // Head "points" to the most recent addition, tail to the oldest one. // The array is of fixed size and I don't think we'll need more than // two or three entries with the current behaviour of G1 pauses. // If the array is full, an easy fix is to look for the pauses with // the shortest gap between them and consolidate them. // For now, we have taken the expedient alternative of forgetting // the oldest entry in the event that +G1UseFixedWindowMMUTracker, thus // potentially violating MMU specs for some time thereafter. G1MMUTrackerQueueElem _array[QueueLength]; int _head_index; int _tail_index; int _no_entries; inline int trim_index(int index) { return (index + QueueLength) % QueueLength; } void remove_expired_entries(double current_time); double calculate_gc_time(double current_time); double longest_pause_internal(double current_time); double when_internal(double current_time, double pause_time); public: G1MMUTrackerQueue(double time_slice, double max_gc_time); virtual void add_pause(double start, double end, bool gc_thread); virtual double longest_pause(double current_time); virtual double when_sec(double current_time, double pause_time); }; #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP