1 /* 2 * Copyright (c) 2020, 2021, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2020 SAP SE. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #include "precompiled.hpp" 27 #include "logging/log.hpp" 28 #include "memory/classLoaderMetaspace.hpp" 29 #include "memory/metaspace.hpp" 30 #include "memory/metaspaceUtils.hpp" 31 #include "memory/metaspace/metaspaceAlignment.hpp" 32 #include "memory/metaspace/chunkManager.hpp" 33 #include "memory/metaspace/internalStats.hpp" 34 #include "memory/metaspace/metaspaceArena.hpp" 35 #include "memory/metaspace/metaspaceArenaGrowthPolicy.hpp" 36 #include "memory/metaspace/metaspaceSettings.hpp" 37 #include "memory/metaspace/metaspaceStatistics.hpp" 38 #include "memory/metaspace/runningCounters.hpp" 39 #include "memory/metaspaceTracer.hpp" 40 #include "oops/compressedKlass.hpp" 41 #include "utilities/align.hpp" 42 #include "utilities/debug.hpp" 43 #include "utilities/globalDefinitions.hpp" 44 45 using metaspace::ChunkManager; 46 using metaspace::MetaspaceArena; 47 using metaspace::ArenaGrowthPolicy; 48 using metaspace::RunningCounters; 49 using metaspace::InternalStats; 50 51 #define LOGFMT "CLMS @" PTR_FORMAT " " 52 #define LOGFMT_ARGS p2i(this) 53 54 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType space_type) : 55 _lock(lock), 56 _space_type(space_type), 57 _non_class_space_arena(NULL), 58 _class_space_arena(NULL) 59 { 60 ChunkManager* const non_class_cm = 61 ChunkManager::chunkmanager_nonclass(); 62 63 const int klass_alignment_words = KlassAlignmentInBytes / BytesPerWord; 64 65 // Initialize non-class Arena 66 _non_class_space_arena = new MetaspaceArena( 67 non_class_cm, 68 ArenaGrowthPolicy::policy_for_space_type(space_type, false), 69 metaspace::MetaspaceMinAlignmentWords, 70 lock, 71 RunningCounters::used_nonclass_counter(), 72 "non-class sm"); 73 74 // If needed, initialize class arena 75 if (Metaspace::using_class_space()) { 76 // Klass instances live in class space and must be aligned correctly. 77 ChunkManager* const class_cm = 78 ChunkManager::chunkmanager_class(); 79 _class_space_arena = new MetaspaceArena( 80 class_cm, 81 ArenaGrowthPolicy::policy_for_space_type(space_type, true), 82 klass_alignment_words, 83 lock, 84 RunningCounters::used_class_counter(), 85 "class sm"); 86 } else { 87 // note for lilliput, this path should be restricted to 32bit only. There, klass alignment 88 // should be compatible with metaspace minimal alignment since we store Klass structures 89 // in regular metaspace. 90 NOT_LP64(STATIC_ASSERT(metaspace::MetaspaceMinAlignmentBytes == KlassAlignmentInBytes)); 91 } 92 93 UL2(debug, "born (nonclass arena: " PTR_FORMAT ", class arena: " PTR_FORMAT ".", 94 p2i(_non_class_space_arena), p2i(_class_space_arena)); 95 } 96 97 ClassLoaderMetaspace::~ClassLoaderMetaspace() { 98 UL(debug, "dies."); 99 100 delete _non_class_space_arena; 101 delete _class_space_arena; 102 103 } 104 105 // Allocate word_size words from Metaspace. 106 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdType) { 107 if (Metaspace::is_class_space_allocation(mdType)) { 108 return class_space_arena()->allocate(word_size); 109 } else { 110 return non_class_space_arena()->allocate(word_size); 111 } 112 } 113 114 // Attempt to expand the GC threshold to be good for at least another word_size words 115 // and allocate. Returns NULL if failure. Used during Metaspace GC. 116 MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdType) { 117 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 118 assert(delta_bytes > 0, "Must be"); 119 120 size_t before = 0; 121 size_t after = 0; 122 bool can_retry = true; 123 MetaWord* res; 124 bool incremented; 125 126 // Each thread increments the HWM at most once. Even if the thread fails to increment 127 // the HWM, an allocation is still attempted. This is because another thread must then 128 // have incremented the HWM and therefore the allocation might still succeed. 129 do { 130 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry); 131 res = allocate(word_size, mdType); 132 } while (!incremented && res == NULL && can_retry); 133 134 if (incremented) { 135 Metaspace::tracer()->report_gc_threshold(before, after, 136 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 137 // Keeping both for now until I am sure the old variant (gc + metaspace) is not needed anymore 138 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 139 UL2(info, "GC threshold increased: " SIZE_FORMAT "->" SIZE_FORMAT ".", before, after); 140 } 141 142 return res; 143 } 144 145 // Prematurely returns a metaspace allocation to the _block_freelists 146 // because it is not needed anymore. 147 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 148 if (Metaspace::using_class_space() && is_class) { 149 class_space_arena()->deallocate(ptr, word_size); 150 } else { 151 non_class_space_arena()->deallocate(ptr, word_size); 152 } 153 DEBUG_ONLY(InternalStats::inc_num_deallocs();) 154 } 155 156 // Update statistics. This walks all in-use chunks. 157 void ClassLoaderMetaspace::add_to_statistics(metaspace::ClmsStats* out) const { 158 if (non_class_space_arena() != NULL) { 159 non_class_space_arena()->add_to_statistics(&out->_arena_stats_nonclass); 160 } 161 if (class_space_arena() != NULL) { 162 class_space_arena()->add_to_statistics(&out->_arena_stats_class); 163 } 164 } 165 166 #ifdef ASSERT 167 void ClassLoaderMetaspace::verify() const { 168 if (non_class_space_arena() != NULL) { 169 non_class_space_arena()->verify(); 170 } 171 if (class_space_arena() != NULL) { 172 class_space_arena()->verify(); 173 } 174 } 175 #endif // ASSERT 176 177 // This only exists for JFR and jcmd VM.classloader_stats. We may want to 178 // change this. Capacity as a stat is of questionable use since it may 179 // contain committed and uncommitted areas. For now we do this to maintain 180 // backward compatibility with JFR. 181 void ClassLoaderMetaspace::calculate_jfr_stats(size_t* p_used_bytes, size_t* p_capacity_bytes) const { 182 // Implement this using the standard statistics objects. 183 size_t used_c = 0, cap_c = 0, used_nc = 0, cap_nc = 0; 184 if (non_class_space_arena() != NULL) { 185 non_class_space_arena()->usage_numbers(&used_nc, NULL, &cap_nc); 186 } 187 if (class_space_arena() != NULL) { 188 class_space_arena()->usage_numbers(&used_c, NULL, &cap_c); 189 } 190 if (p_used_bytes != NULL) { 191 *p_used_bytes = used_c + used_nc; 192 } 193 if (p_capacity_bytes != NULL) { 194 *p_capacity_bytes = cap_c + cap_nc; 195 } 196 } 197