1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5  * This code is free software; you can redistribute it and/or modify it
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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).
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15  * You should have received a copy of the GNU General Public License version
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24 
25 #include "precompiled.hpp"
26 #include "gc/g1/g1RegionMarkStatsCache.inline.hpp"
27 #include "memory/allocation.inline.hpp"
28 
G1RegionMarkStatsCache(G1RegionMarkStats * target,uint max_regions,uint num_cache_entries)29 G1RegionMarkStatsCache::G1RegionMarkStatsCache(G1RegionMarkStats* target, uint max_regions, uint num_cache_entries) :
30   _target(target),
31   _num_stats(max_regions),
32   _cache(NULL),
33   _num_cache_entries(num_cache_entries),
34   _cache_hits(0),
35   _cache_misses(0),
36   _num_cache_entries_mask(_num_cache_entries - 1) {
37 
38   guarantee(is_power_of_2(num_cache_entries),
39             "Number of cache entries must be power of two, but is %u", num_cache_entries);
40   _cache = NEW_C_HEAP_ARRAY(G1RegionMarkStatsCacheEntry, _num_cache_entries, mtGC);
41 }
42 
~G1RegionMarkStatsCache()43 G1RegionMarkStatsCache::~G1RegionMarkStatsCache() {
44   FREE_C_HEAP_ARRAY(G1RegionMarkStatsCacheEntry, _cache);
45 }
46 
47 // Evict all remaining statistics, returning cache hits and misses.
evict_all()48 Pair<size_t, size_t> G1RegionMarkStatsCache::evict_all() {
49   for (uint i = 0; i < _num_cache_entries; i++) {
50     evict(i);
51   }
52   return Pair<size_t,size_t>(_cache_hits, _cache_misses);
53 }
54 
55 // Reset all cache entries to their default values.
reset()56 void G1RegionMarkStatsCache::reset() {
57   _cache_hits = 0;
58   _cache_misses = 0;
59 
60   for (uint i = 0; i < _num_cache_entries; i++) {
61     _cache[i].clear();
62   }
63 }
64