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/chunkManager.hpp"
32 #include "memory/metaspace/internalStats.hpp"
33 #include "memory/metaspace/metaspaceArena.hpp"
34 #include "memory/metaspace/metaspaceArenaGrowthPolicy.hpp"
35 #include "memory/metaspace/metaspaceSettings.hpp"
36 #include "memory/metaspace/metaspaceStatistics.hpp"
37 #include "memory/metaspace/runningCounters.hpp"
38 #include "memory/metaspaceTracer.hpp"
39 #include "utilities/debug.hpp"
40
41 using metaspace::ChunkManager;
42 using metaspace::MetaspaceArena;
43 using metaspace::ArenaGrowthPolicy;
44 using metaspace::RunningCounters;
45 using metaspace::InternalStats;
46
47 #define LOGFMT "CLMS @" PTR_FORMAT " "
48 #define LOGFMT_ARGS p2i(this)
49
50 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType space_type) :
51 _lock(lock),
52 _space_type(space_type),
53 _non_class_space_arena(NULL),
54 _class_space_arena(NULL)
55 {
56 ChunkManager* const non_class_cm =
57 ChunkManager::chunkmanager_nonclass();
58
59 // Initialize non-class Arena
60 _non_class_space_arena = new MetaspaceArena(
61 non_class_cm,
62 ArenaGrowthPolicy::policy_for_space_type(space_type, false),
63 lock,
64 RunningCounters::used_nonclass_counter(),
65 "non-class sm");
66
67 // If needed, initialize class arena
68 if (Metaspace::using_class_space()) {
69 ChunkManager* const class_cm =
70 ChunkManager::chunkmanager_class();
71 _class_space_arena = new MetaspaceArena(
72 class_cm,
73 ArenaGrowthPolicy::policy_for_space_type(space_type, true),
74 lock,
75 RunningCounters::used_class_counter(),
76 "class sm");
77 }
78
79 UL2(debug, "born (nonclass arena: " PTR_FORMAT ", class arena: " PTR_FORMAT ".",
80 p2i(_non_class_space_arena), p2i(_class_space_arena));
81 }
82
83 ClassLoaderMetaspace::~ClassLoaderMetaspace() {
84 UL(debug, "dies.");
85
86 delete _non_class_space_arena;
87 delete _class_space_arena;
88
89 }
90
91 // Allocate word_size words from Metaspace.
92 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdType) {
93 if (Metaspace::is_class_space_allocation(mdType)) {
94 return class_space_arena()->allocate(word_size);
95 } else {
96 return non_class_space_arena()->allocate(word_size);
97 }
98 }
99
100 // Attempt to expand the GC threshold to be good for at least another word_size words
101 // and allocate. Returns NULL if failure. Used during Metaspace GC.
102 MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdType) {
103 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
104 assert(delta_bytes > 0, "Must be");
105
106 size_t before = 0;
107 size_t after = 0;
108 bool can_retry = true;
109 MetaWord* res;
110 bool incremented;
111
112 // Each thread increments the HWM at most once. Even if the thread fails to increment
113 // the HWM, an allocation is still attempted. This is because another thread must then
114 // have incremented the HWM and therefore the allocation might still succeed.
115 do {
116 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);
117 res = allocate(word_size, mdType);
118 } while (!incremented && res == NULL && can_retry);
119
120 if (incremented) {
121 Metaspace::tracer()->report_gc_threshold(before, after,
122 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
123 // Keeping both for now until I am sure the old variant (gc + metaspace) is not needed anymore
124 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
125 UL2(info, "GC threshold increased: " SIZE_FORMAT "->" SIZE_FORMAT ".", before, after);
126 }
127
128 return res;
129 }
130
131 // Prematurely returns a metaspace allocation to the _block_freelists
132 // because it is not needed anymore.
133 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
134 if (Metaspace::using_class_space() && is_class) {
135 class_space_arena()->deallocate(ptr, word_size);
136 } else {
137 non_class_space_arena()->deallocate(ptr, word_size);
138 }
139 DEBUG_ONLY(InternalStats::inc_num_deallocs();)
140 }
141
142 // Update statistics. This walks all in-use chunks.
143 void ClassLoaderMetaspace::add_to_statistics(metaspace::ClmsStats* out) const {
144 if (non_class_space_arena() != NULL) {
145 non_class_space_arena()->add_to_statistics(&out->_arena_stats_nonclass);
146 }
147 if (class_space_arena() != NULL) {
148 class_space_arena()->add_to_statistics(&out->_arena_stats_class);
149 }
150 }
151
152 #ifdef ASSERT
153 void ClassLoaderMetaspace::verify() const {
154 if (non_class_space_arena() != NULL) {
155 non_class_space_arena()->verify();
156 }
157 if (class_space_arena() != NULL) {
158 class_space_arena()->verify();
159 }
160 }
161 #endif // ASSERT
162
163 // This only exists for JFR and jcmd VM.classloader_stats. We may want to
164 // change this. Capacity as a stat is of questionable use since it may
165 // contain committed and uncommitted areas. For now we do this to maintain
166 // backward compatibility with JFR.
167 void ClassLoaderMetaspace::calculate_jfr_stats(size_t* p_used_bytes, size_t* p_capacity_bytes) const {
168 // Implement this using the standard statistics objects.
169 size_t used_c = 0, cap_c = 0, used_nc = 0, cap_nc = 0;
170 if (non_class_space_arena() != NULL) {
171 non_class_space_arena()->usage_numbers(&used_nc, NULL, &cap_nc);
172 }
173 if (class_space_arena() != NULL) {
174 class_space_arena()->usage_numbers(&used_c, NULL, &cap_c);
175 }
176 if (p_used_bytes != NULL) {
177 *p_used_bytes = used_c + used_nc;
178 }
179 if (p_capacity_bytes != NULL) {
180 *p_capacity_bytes = cap_c + cap_nc;
181 }
182 }
183