1 /*
2 * Copyright (c) 2020, 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
28 #include "logging/log.hpp"
29 #include "memory/metaspace/msArena.hpp"
30 #include "memory/metaspace/msArenaGrowthPolicy.hpp"
31 #include "memory/metaspace/msChunkManager.hpp"
32 #include "memory/metaspace/msInternalStats.hpp"
33 #include "memory/metaspace/msRunningCounters.hpp"
34 #include "memory/metaspace/msSettings.hpp"
35 #include "memory/metaspace/msStatistics.hpp"
36 #include "memory/metaspace.hpp"
37 #include "memory/metaspaceTracer.hpp"
38 #include "runtime/atomic.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 static bool use_class_space(bool is_class) {
51 if (Metaspace::using_class_space() && is_class) {
52 return true;
53 }
54 return false;
55 }
56
57 static bool use_class_space(Metaspace::MetadataType mdType) {
58 return use_class_space(Metaspace::is_class_space_allocation(mdType));
59 }
60
61 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType space_type)
62 : _lock(lock)
63 , _space_type(space_type)
64 , _non_class_space_arena(NULL)
65 , _class_space_arena(NULL)
66 {
67 ChunkManager* const non_class_cm =
68 ChunkManager::chunkmanager_nonclass();
69
70 // Initialize non-class Arena
71 _non_class_space_arena = new MetaspaceArena(
72 non_class_cm,
73 ArenaGrowthPolicy::policy_for_space_type(space_type, false),
74 lock,
75 RunningCounters::used_nonclass_counter(),
76 "non-class sm");
77
78 // If needed, initialize class arena
79 if (Metaspace::using_class_space()) {
80 ChunkManager* const class_cm =
81 ChunkManager::chunkmanager_class();
82 _class_space_arena = new MetaspaceArena(
83 class_cm,
84 ArenaGrowthPolicy::policy_for_space_type(space_type, true),
85 lock,
86 RunningCounters::used_class_counter(),
87 "class sm");
88 }
89
90 UL2(debug, "born (SpcMgr nonclass: " PTR_FORMAT ", SpcMgr class: " PTR_FORMAT ".",
91 p2i(_non_class_space_arena), p2i(_class_space_arena));
92 }
93
94 ClassLoaderMetaspace::~ClassLoaderMetaspace() {
95 Metaspace::assert_not_frozen();
96
97 UL(debug, "dies.");
98
99 delete _non_class_space_arena;
100 delete _class_space_arena;
101
102 }
103
104 // Allocate word_size words from Metaspace.
105 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdType) {
106 Metaspace::assert_not_frozen();
107 if (use_class_space(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 Metaspace::assert_not_frozen();
118 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
119 assert(delta_bytes > 0, "Must be");
120
121 size_t before = 0;
122 size_t after = 0;
123 bool can_retry = true;
124 MetaWord* res;
125 bool incremented;
126
127 // Each thread increments the HWM at most once. Even if the thread fails to increment
128 // the HWM, an allocation is still attempted. This is because another thread must then
129 // have incremented the HWM and therefore the allocation might still succeed.
130 do {
131 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);
132 res = allocate(word_size, mdType);
133 } while (!incremented && res == NULL && can_retry);
134
135 if (incremented) {
136 Metaspace::tracer()->report_gc_threshold(before, after,
137 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
138 // Keeping both for now until I am sure the old variant (gc + metaspace) is not needed anymore
139 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
140 UL2(info, "GC threshold increased: " SIZE_FORMAT "->" SIZE_FORMAT ".", before, after);
141 }
142
143 return res;
144 }
145
146 // Prematurely returns a metaspace allocation to the _block_freelists
147 // because it is not needed anymore.
148 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
149
150 Metaspace::assert_not_frozen();
151
152 if (use_class_space(is_class)) {
153 class_space_arena()->deallocate(ptr, word_size);
154 } else {
155 non_class_space_arena()->deallocate(ptr, word_size);
156 }
157
158 DEBUG_ONLY(InternalStats::inc_num_deallocs();)
159
160 }
161
162 // Update statistics. This walks all in-use chunks.
163 void ClassLoaderMetaspace::add_to_statistics(metaspace::ClmsStats* out) const {
164 if (non_class_space_arena() != NULL) {
165 non_class_space_arena()->add_to_statistics(&out->_arena_stats_nonclass);
166 }
167 if (class_space_arena() != NULL) {
168 class_space_arena()->add_to_statistics(&out->_arena_stats_class);
169 }
170 }
171
172 #ifdef ASSERT
173 void ClassLoaderMetaspace::verify() const {
174 if (non_class_space_arena() != NULL) {
175 non_class_space_arena()->verify();
176 }
177 if (class_space_arena() != NULL) {
178 class_space_arena()->verify();
179 }
180 }
181 #endif // ASSERT
182
183 // This only exists for JFR and jcmd VM.classloader_stats. We may want to
184 // change this. Capacity as a stat is of questionable use since it may
185 // contain committed and uncommitted areas. For now we do this to maintain
186 // backward compatibility with JFR.
187 void ClassLoaderMetaspace::calculate_jfr_stats(size_t* p_used_bytes, size_t* p_capacity_bytes) const {
188 // Implement this using the standard statistics objects.
189 size_t used_c = 0, cap_c = 0, used_nc = 0, cap_nc = 0;
190 if (non_class_space_arena() != NULL) {
191 non_class_space_arena()->usage_numbers(&used_nc, NULL, &cap_nc);
192 }
193 if (class_space_arena() != NULL) {
194 class_space_arena()->usage_numbers(&used_c, NULL, &cap_c);
195 }
196 if (p_used_bytes != NULL) {
197 *p_used_bytes = used_c + used_nc;
198 }
199 if (p_capacity_bytes != NULL) {
200 *p_capacity_bytes = cap_c + cap_nc;
201 }
202 }
203