Bug Summary

File:jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp
Warning:line 91, column 22
Value stored to 'orig_level' during its initialization is never read

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name chunkManager.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -mthread-model posix -fno-delete-null-pointer-checks -mframe-pointer=all -relaxed-aliasing -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -dwarf-column-info -fno-split-dwarf-inlining -debugger-tuning=gdb -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/libjvm/objs/precompiled -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D _GNU_SOURCE -D _REENTRANT -D LIBC=gnu -D LINUX -D VM_LITTLE_ENDIAN -D _LP64=1 -D ASSERT -D CHECK_UNHANDLED_OOPS -D TARGET_ARCH_x86 -D INCLUDE_SUFFIX_OS=_linux -D INCLUDE_SUFFIX_CPU=_x86 -D INCLUDE_SUFFIX_COMPILER=_gcc -D TARGET_COMPILER_gcc -D AMD64 -D HOTSPOT_LIB_ARCH="amd64" -D COMPILER1 -D COMPILER2 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc/adfiles -I /home/daniel/Projects/java/jdk/src/hotspot/share -I /home/daniel/Projects/java/jdk/src/hotspot/os/linux -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix -I /home/daniel/Projects/java/jdk/src/hotspot/cpu/x86 -I /home/daniel/Projects/java/jdk/src/hotspot/os_cpu/linux_x86 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc -I /home/daniel/Projects/java/jdk/src/hotspot/share/precompiled -I /home/daniel/Projects/java/jdk/src/hotspot/share/include -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix/include -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base/linux -I /home/daniel/Projects/java/jdk/src/java.base/share/native/libjimage -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc/adfiles -I /home/daniel/Projects/java/jdk/src/hotspot/share -I /home/daniel/Projects/java/jdk/src/hotspot/os/linux -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix -I /home/daniel/Projects/java/jdk/src/hotspot/cpu/x86 -I /home/daniel/Projects/java/jdk/src/hotspot/os_cpu/linux_x86 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc -D _FORTIFY_SOURCE=2 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-format-zero-length -Wno-unused-parameter -Wno-unused -Wno-parentheses -Wno-comment -Wno-unknown-pragmas -Wno-address -Wno-delete-non-virtual-dtor -Wno-char-subscripts -Wno-array-bounds -Wno-int-in-bool-context -Wno-ignored-qualifiers -Wno-missing-field-initializers -Wno-implicit-fallthrough -Wno-empty-body -Wno-strict-overflow -Wno-sequence-point -Wno-maybe-uninitialized -Wno-misleading-indentation -Wno-cast-function-type -Wno-shift-negative-value -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /home/daniel/Projects/java/jdk/make/hotspot -ferror-limit 19 -fmessage-length 0 -fvisibility hidden -stack-protector 1 -fno-rtti -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -faddrsig -o /home/daniel/Projects/java/scan/2021-12-21-193737-8510-1 -x c++ /home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp
1/*
2 * Copyright (c) 2018, 2021, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2018, 2021 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 "logging/logStream.hpp"
29#include "memory/metaspace/chunkManager.hpp"
30#include "memory/metaspace/internalStats.hpp"
31#include "memory/metaspace/metachunk.hpp"
32#include "memory/metaspace/metaspaceArenaGrowthPolicy.hpp"
33#include "memory/metaspace/metaspaceCommon.hpp"
34#include "memory/metaspace/metaspaceContext.hpp"
35#include "memory/metaspace/metaspaceSettings.hpp"
36#include "memory/metaspace/metaspaceStatistics.hpp"
37#include "memory/metaspace/virtualSpaceList.hpp"
38#include "memory/metaspace/virtualSpaceNode.hpp"
39#include "runtime/mutexLocker.hpp"
40#include "utilities/debug.hpp"
41#include "utilities/globalDefinitions.hpp"
42
43namespace metaspace {
44
45#define LOGFMT"ChkMgr @" "0x%016" "l" "x" " (%s)" "ChkMgr @" PTR_FORMAT"0x%016" "l" "x" " (%s)"
46#define LOGFMT_ARGSp2i(this), this->_name p2i(this), this->_name
47
48// Return a single chunk to the freelist and adjust accounting. No merge is attempted.
49void ChunkManager::return_chunk_simple_locked(Metachunk* c) {
50 assert_lock_strong(Metaspace_lock);
51 DEBUG_ONLY(c->verify())c->verify();
52 _chunks.add(c);
53 c->reset_used_words();
54 // Tracing
55 log_debug(metaspace)(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChunkManager %s: returned chunk " METACHUNK_FORMAT"@" "0x%016" "l" "x" ", %c, base " "0x%016" "l" "x" ", level "
"lv%.2d" ".",
56 _name, METACHUNK_FORMAT_ARGS(c)p2i(c), c->get_state_char(), p2i(c->base()), c->level
());
57}
58
59// Creates a chunk manager with a given name (which is for debug purposes only)
60// and an associated space list which will be used to request new chunks from
61// (see get_chunk())
62ChunkManager::ChunkManager(const char* name, VirtualSpaceList* space_list) :
63 _vslist(space_list),
64 _name(name),
65 _chunks()
66{
67}
68
69// Given a chunk, split it into a target chunk of a smaller size (higher target level)
70// and at least one, possible several splinter chunks.
71// The original chunk must be outside of the freelist and its state must be free.
72// The splinter chunks are added to the freelist.
73// The resulting target chunk will be located at the same address as the original
74// chunk, but it will of course be smaller (of a higher level).
75// The committed areas within the original chunk carry over to the resulting
76// chunks.
77void ChunkManager::split_chunk_and_add_splinters(Metachunk* c, chunklevel_t target_level) {
78 assert_lock_strong(Metaspace_lock);
79 assert(c->is_free(), "chunk to be split must be free.")do { if (!(c->is_free())) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 79, "assert(" "c->is_free()" ") failed", "chunk to be split must be free."
); ::breakpoint(); } } while (0);
80 assert(c->level() < target_level, "Target level must be higher than current level.")do { if (!(c->level() < target_level)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 80, "assert(" "c->level() < target_level" ") failed",
"Target level must be higher than current level."); ::breakpoint
(); } } while (0);
81 assert(c->prev() == NULL && c->next() == NULL, "Chunk must be outside of any list.")do { if (!(c->prev() == __null && c->next() == __null
)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 81, "assert(" "c->prev() == __null && c->next() == __null"
") failed", "Chunk must be outside of any list."); ::breakpoint
(); } } while (0);
82
83 DEBUG_ONLY(chunklevel::check_valid_level(target_level);)chunklevel::check_valid_level(target_level);
84 DEBUG_ONLY(c->verify();)c->verify();
85
86 UL2(debug, "splitting chunk " METACHUNK_FORMAT " to " CHKLVL_FORMAT ".",(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "splitting chunk " "@" "0x%016" "l" "x" ", %c, base "
"0x%016" "l" "x" ", level " "lv%.2d" " to " "lv%.2d" ".", p2i
(this), this->_name, p2i(c), c->get_state_char(), p2i(c
->base()), c->level(), target_level);
87 METACHUNK_FORMAT_ARGS(c), target_level)(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "splitting chunk " "@" "0x%016" "l" "x" ", %c, base "
"0x%016" "l" "x" ", level " "lv%.2d" " to " "lv%.2d" ".", p2i
(this), this->_name, p2i(c), c->get_state_char(), p2i(c
->base()), c->level(), target_level);;
88
89 DEBUG_ONLY(size_t committed_words_before = c->committed_words();)size_t committed_words_before = c->committed_words();
90
91 const chunklevel_t orig_level = c->level();
Value stored to 'orig_level' during its initialization is never read
92 c->vsnode()->split(target_level, c, &_chunks);
93
94 // Splitting should never fail.
95 assert(c->level() == target_level, "Sanity")do { if (!(c->level() == target_level)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 95, "assert(" "c->level() == target_level" ") failed", "Sanity"
); ::breakpoint(); } } while (0);
96
97 // The size of the committed portion should not change (subject to the reduced chunk size of course)
98#ifdef ASSERT1
99 if (committed_words_before > c->word_size()) {
100 assert(c->is_fully_committed(), "Sanity")do { if (!(c->is_fully_committed())) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 100, "assert(" "c->is_fully_committed()" ") failed", "Sanity"
); ::breakpoint(); } } while (0);
101 } else {
102 assert(c->committed_words() == committed_words_before, "Sanity")do { if (!(c->committed_words() == committed_words_before)
) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 102, "assert(" "c->committed_words() == committed_words_before"
") failed", "Sanity"); ::breakpoint(); } } while (0);
103 }
104 c->verify();
105 verify_locked();
106 SOMETIMES(c->vsnode()->verify_locked();){ static int counter_ = 0; if (VerifyMetaspaceInterval > 0
) { counter_++; if (counter_ >= VerifyMetaspaceInterval) {
counter_ = 0; { c->vsnode()->verify_locked(); } } } }
107#endif
108 InternalStats::inc_num_chunk_splits();
109}
110
111// On success, returns a chunk of level of <preferred_level>, but at most <max_level>.
112// The first first <min_committed_words> of the chunk are guaranteed to be committed.
113// On error, will return NULL.
114//
115// This function may fail for two reasons:
116// - Either we are unable to reserve space for a new chunk (if the underlying VirtualSpaceList
117// is non-expandable but needs expanding - aka out of compressed class space).
118// - Or, if the necessary space cannot be committed because we hit a commit limit.
119// This may be either the GC threshold or MaxMetaspaceSize.
120Metachunk* ChunkManager::get_chunk(chunklevel_t preferred_level, chunklevel_t max_level, size_t min_committed_words) {
121 assert(preferred_level <= max_level, "Sanity")do { if (!(preferred_level <= max_level)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 121, "assert(" "preferred_level <= max_level" ") failed"
, "Sanity"); ::breakpoint(); } } while (0);
122 assert(chunklevel::level_fitting_word_size(min_committed_words) >= max_level, "Sanity")do { if (!(chunklevel::level_fitting_word_size(min_committed_words
) >= max_level)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 122, "assert(" "chunklevel::level_fitting_word_size(min_committed_words) >= max_level"
") failed", "Sanity"); ::breakpoint(); } } while (0);
123
124 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
125
126 DEBUG_ONLY(verify_locked();)verify_locked();
127 DEBUG_ONLY(chunklevel::check_valid_level(max_level);)chunklevel::check_valid_level(max_level);
128 DEBUG_ONLY(chunklevel::check_valid_level(preferred_level);)chunklevel::check_valid_level(preferred_level);
129
130 UL2(debug, "requested chunk: pref_level: " CHKLVL_FORMAT(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "requested chunk: pref_level: " "lv%.2d" ", max_level: "
"lv%.2d" ", min committed size: " "%" "l" "u" ".", p2i(this)
, this->_name, preferred_level, max_level, min_committed_words
);
131 ", max_level: " CHKLVL_FORMAT ", min committed size: " SIZE_FORMAT ".",(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "requested chunk: pref_level: " "lv%.2d" ", max_level: "
"lv%.2d" ", min committed size: " "%" "l" "u" ".", p2i(this)
, this->_name, preferred_level, max_level, min_committed_words
);
132 preferred_level, max_level, min_committed_words)(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "requested chunk: pref_level: " "lv%.2d" ", max_level: "
"lv%.2d" ", min committed size: " "%" "l" "u" ".", p2i(this)
, this->_name, preferred_level, max_level, min_committed_words
);;
133
134 // First, optimistically look for a chunk which is already committed far enough to hold min_word_size.
135
136 // 1) Search best or smaller committed chunks (first attempt):
137 // Start at the preferred chunk size and work your way down (level up).
138 // But for now, only consider chunks larger than a certain threshold -
139 // this is to prevent large loaders (eg boot) from unnecessarily gobbling up
140 // all the tiny splinter chunks lambdas leave around.
141 Metachunk* c = NULL__null;
142 c = _chunks.search_chunk_ascending(preferred_level, MIN2((chunklevel_t)(preferred_level + 2), max_level), min_committed_words);
143
144 // 2) Search larger committed chunks:
145 // If that did not yield anything, look at larger chunks, which may be committed. We would have to split
146 // them first, of course.
147 if (c == NULL__null) {
148 c = _chunks.search_chunk_descending(preferred_level, min_committed_words);
149 }
150 // 3) Search best or smaller committed chunks (second attempt):
151 // Repeat (1) but now consider even the tiniest chunks as long as they are large enough to hold the
152 // committed min size.
153 if (c == NULL__null) {
154 c = _chunks.search_chunk_ascending(preferred_level, max_level, min_committed_words);
155 }
156 // if we did not get anything yet, there are no free chunks commmitted enough. Repeat search but look for uncommitted chunks too:
157 // 4) Search best or smaller chunks, can be uncommitted:
158 if (c == NULL__null) {
159 c = _chunks.search_chunk_ascending(preferred_level, max_level, 0);
160 }
161 // 5) Search a larger uncommitted chunk:
162 if (c == NULL__null) {
163 c = _chunks.search_chunk_descending(preferred_level, 0);
164 }
165
166 if (c != NULL__null) {
167 UL(trace, "taken from freelist.")(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Trace))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Trace>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "taken from freelist.", p2i(this), this->_name
);;
168 }
169
170 // Failing all that, allocate a new root chunk from the connected virtual space.
171 // This may fail if the underlying vslist cannot be expanded (e.g. compressed class space)
172 if (c == NULL__null) {
173 c = _vslist->allocate_root_chunk();
174 if (c == NULL__null) {
175 UL(info, "failed to get new root chunk.")(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "failed to get new root chunk.", p2i(this), this
->_name);;
176 } else {
177 assert(c->level() == chunklevel::ROOT_CHUNK_LEVEL, "root chunk expected")do { if (!(c->level() == chunklevel::ROOT_CHUNK_LEVEL)) { (
*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 177, "assert(" "c->level() == chunklevel::ROOT_CHUNK_LEVEL"
") failed", "root chunk expected"); ::breakpoint(); } } while
(0);
178 UL(debug, "allocated new root chunk.")(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "allocated new root chunk.", p2i(this), this->
_name);;
179 }
180 }
181 if (c == NULL__null) {
182 // If we end up here, we found no match in the freelists and were unable to get a new
183 // root chunk (so we used up all address space, e.g. out of CompressedClassSpace).
184 UL2(info, "failed to get chunk (preferred level: " CHKLVL_FORMAT(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "failed to get chunk (preferred level: " "lv%.2d"
", max level " "lv%.2d" ".", p2i(this), this->_name, preferred_level
, max_level);
185 ", max level " CHKLVL_FORMAT ".", preferred_level, max_level)(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "failed to get chunk (preferred level: " "lv%.2d"
", max level " "lv%.2d" ".", p2i(this), this->_name, preferred_level
, max_level);;
186 c = NULL__null;
187 }
188 if (c != NULL__null) {
189 // Now we have a chunk.
190 // It may be larger than what the caller wanted, so we may want to split it. This should
191 // always work.
192 if (c->level() < preferred_level) {
193 split_chunk_and_add_splinters(c, preferred_level);
194 assert(c->level() == preferred_level, "split failed?")do { if (!(c->level() == preferred_level)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 194, "assert(" "c->level() == preferred_level" ") failed"
, "split failed?"); ::breakpoint(); } } while (0);
195 }
196 // Attempt to commit the chunk (depending on settings, we either fully commit it or just
197 // commit enough to get the caller going). That may fail if we hit a commit limit. In
198 // that case put the chunk back to the freelist (re-merging it with its neighbors if we
199 // did split it) and return NULL.
200 const size_t to_commit = Settings::new_chunks_are_fully_committed() ? c->word_size() : min_committed_words;
201 if (c->committed_words() < to_commit) {
202 if (c->ensure_committed_locked(to_commit) == false) {
203 UL2(info, "failed to commit " SIZE_FORMAT " words on chunk " METACHUNK_FORMAT ".",(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "failed to commit " "%" "l" "u" " words on chunk "
"@" "0x%016" "l" "x" ", %c, base " "0x%016" "l" "x" ", level "
"lv%.2d" ".", p2i(this), this->_name, to_commit, p2i(c), c
->get_state_char(), p2i(c->base()), c->level());
204 to_commit, METACHUNK_FORMAT_ARGS(c))(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "failed to commit " "%" "l" "u" " words on chunk "
"@" "0x%016" "l" "x" ", %c, base " "0x%016" "l" "x" ", level "
"lv%.2d" ".", p2i(this), this->_name, to_commit, p2i(c), c
->get_state_char(), p2i(c->base()), c->level());;
205 return_chunk_locked(c);
206 c = NULL__null;
207 }
208 }
209 if (c != NULL__null) {
210 // Still here? We have now a good chunk, all is well.
211 assert(c->committed_words() >= min_committed_words, "Sanity")do { if (!(c->committed_words() >= min_committed_words)
) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 211, "assert(" "c->committed_words() >= min_committed_words"
") failed", "Sanity"); ::breakpoint(); } } while (0);
212
213 // Any chunk returned from ChunkManager shall be marked as in use.
214 c->set_in_use();
215
216 UL2(debug, "handing out chunk " METACHUNK_FORMAT ".", METACHUNK_FORMAT_ARGS(c))(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "handing out chunk " "@" "0x%016" "l" "x" ", %c, base "
"0x%016" "l" "x" ", level " "lv%.2d" ".", p2i(this), this->
_name, p2i(c), c->get_state_char(), p2i(c->base()), c->
level());;
217
218 InternalStats::inc_num_chunks_taken_from_freelist();
219
220 SOMETIMES(c->vsnode()->verify_locked();){ static int counter_ = 0; if (VerifyMetaspaceInterval > 0
) { counter_++; if (counter_ >= VerifyMetaspaceInterval) {
counter_ = 0; { c->vsnode()->verify_locked(); } } } }
221 }
222 }
223
224 DEBUG_ONLY(verify_locked();)verify_locked();
225 return c;
226}
227
228// Return a single chunk to the ChunkManager and adjust accounting. May merge chunk
229// with neighbors.
230// As a side effect this removes the chunk from whatever list it has been in previously.
231// Happens after a Classloader was unloaded and releases its metaspace chunks.
232// !! Note: this may invalidate the chunk. Do not access the chunk after
233// this function returns !!
234void ChunkManager::return_chunk(Metachunk* c) {
235 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
236 return_chunk_locked(c);
237}
238
239// See return_chunk().
240void ChunkManager::return_chunk_locked(Metachunk* c) {
241 assert_lock_strong(Metaspace_lock);
242 UL2(debug, ": returning chunk " METACHUNK_FORMAT ".", METACHUNK_FORMAT_ARGS(c))(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " ": returning chunk " "@" "0x%016" "l" "x" ", %c, base "
"0x%016" "l" "x" ", level " "lv%.2d" ".", p2i(this), this->
_name, p2i(c), c->get_state_char(), p2i(c->base()), c->
level());;
243 DEBUG_ONLY(c->verify();)c->verify();
244 assert(contains_chunk(c) == false, "A chunk to be added to the freelist must not be in the freelist already.")do { if (!(contains_chunk(c) == false)) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 244, "assert(" "contains_chunk(c) == false" ") failed", "A chunk to be added to the freelist must not be in the freelist already."
); ::breakpoint(); } } while (0);
245 assert(c->is_in_use() || c->is_free(), "Unexpected chunk state")do { if (!(c->is_in_use() || c->is_free())) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 245, "assert(" "c->is_in_use() || c->is_free()" ") failed"
, "Unexpected chunk state"); ::breakpoint(); } } while (0);
246 assert(!c->in_list(), "Remove from list first")do { if (!(!c->in_list())) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 246, "assert(" "!c->in_list()" ") failed", "Remove from list first"
); ::breakpoint(); } } while (0);
247
248 c->set_free();
249 c->reset_used_words();
250 const chunklevel_t orig_lvl = c->level();
251
252 Metachunk* merged = NULL__null;
253 if (!c->is_root_chunk()) {
254 // Only attempt merging if we are not of the lowest level already.
255 merged = c->vsnode()->merge(c, &_chunks);
256 }
257
258 if (merged != NULL__null) {
259 InternalStats::inc_num_chunk_merges();
260 DEBUG_ONLY(merged->verify())merged->verify();
261 // We did merge chunks and now have a bigger chunk.
262 assert(merged->level() < orig_lvl, "Sanity")do { if (!(merged->level() < orig_lvl)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 262, "assert(" "merged->level() < orig_lvl" ") failed"
, "Sanity"); ::breakpoint(); } } while (0);
263 UL2(debug, "merged into chunk " METACHUNK_FORMAT ".", METACHUNK_FORMAT_ARGS(merged))(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Debug))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Debug>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "merged into chunk " "@" "0x%016" "l" "x" ", %c, base "
"0x%016" "l" "x" ", level " "lv%.2d" ".", p2i(this), this->
_name, p2i(merged), merged->get_state_char(), p2i(merged->
base()), merged->level());;
264 c = merged;
265 }
266
267 return_chunk_simple_locked(c);
268 DEBUG_ONLY(verify_locked();)verify_locked();
269 SOMETIMES(c->vsnode()->verify_locked();){ static int counter_ = 0; if (VerifyMetaspaceInterval > 0
) { counter_++; if (counter_ >= VerifyMetaspaceInterval) {
counter_ = 0; { c->vsnode()->verify_locked(); } } } }
270 InternalStats::inc_num_chunks_returned_to_freelist();
271}
272
273// Given a chunk c, whose state must be "in-use" and must not be a root chunk, attempt to
274// enlarge it in place by claiming its trailing buddy.
275//
276// This will only work if c is the leader of the buddy pair and the trailing buddy is free.
277//
278// If successful, the follower chunk will be removed from the freelists, the leader chunk c will
279// double in size (level decreased by one).
280//
281// On success, true is returned, false otherwise.
282bool ChunkManager::attempt_enlarge_chunk(Metachunk* c) {
283 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
284 return c->vsnode()->attempt_enlarge_chunk(c, &_chunks);
285}
286
287static void print_word_size_delta(outputStream* st, size_t word_size_1, size_t word_size_2) {
288 if (word_size_1 == word_size_2) {
289 print_scaled_words(st, word_size_1);
290 st->print (" (no change)");
291 } else {
292 print_scaled_words(st, word_size_1);
293 st->print("->");
294 print_scaled_words(st, word_size_2);
295 st->print(" (");
296 if (word_size_2 <= word_size_1) {
297 st->print("-");
298 print_scaled_words(st, word_size_1 - word_size_2);
299 } else {
300 st->print("+");
301 print_scaled_words(st, word_size_2 - word_size_1);
302 }
303 st->print(")");
304 }
305}
306
307void ChunkManager::purge() {
308 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
309 UL(info, ": reclaiming memory...")(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " ": reclaiming memory...", p2i(this), this->_name
);;
310
311 const size_t reserved_before = _vslist->reserved_words();
312 const size_t committed_before = _vslist->committed_words();
313
314 // We return unused memory to the Operating System: we iterate over all
315 // free chunks and uncommit the backing memory of those large enough to
316 // contain one or multiple commit granules (chunks larger than a granule
317 // always cover a whole number of granules and start at a granule boundary).
318 if (Settings::uncommit_free_chunks()) {
319 const chunklevel_t max_level =
320 chunklevel::level_fitting_word_size(Settings::commit_granule_words());
321 for (chunklevel_t l = chunklevel::LOWEST_CHUNK_LEVEL;
322 l <= max_level;
323 l++) {
324 // Since we uncommit all chunks at this level, we do not break the "committed chunks are
325 // at the front of the list" condition.
326 for (Metachunk* c = _chunks.first_at_level(l); c != NULL__null; c = c->next()) {
327 c->uncommit_locked();
328 }
329 }
330 }
331
332 const size_t reserved_after = _vslist->reserved_words();
333 const size_t committed_after = _vslist->committed_words();
334
335 // Print a nice report.
336 if (reserved_after == reserved_before && committed_after == committed_before) {
337 UL(info, "nothing reclaimed.")(!(LogImpl<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG)>::is_level(LogLevel::Info))) ? (void)0 : LogImpl
<(LogTag::_metaspace), (LogTag::__NO_TAG), (LogTag::__NO_TAG
), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG)
>::write<LogLevel::Info>("ChkMgr @" "0x%016" "l" "x"
" (%s)" ": " "nothing reclaimed.", p2i(this), this->_name
);;
338 } else {
339 LogTarget(Info, metaspace)LogTargetImpl<LogLevel::Info, (LogTag::_metaspace), (LogTag
::__NO_TAG), (LogTag::__NO_TAG), (LogTag::__NO_TAG), (LogTag::
__NO_TAG), (LogTag::__NO_TAG)> lt;
340 if (lt.is_enabled()) {
341 LogStream ls(lt);
342 ls.print_cr(LOGFMT"ChkMgr @" "0x%016" "l" "x" " (%s)" ": finished reclaiming memory: ", LOGFMT_ARGSp2i(this), this->_name);
343 ls.print("reserved: ");
344 print_word_size_delta(&ls, reserved_before, reserved_after);
345 ls.cr();
346 ls.print("committed: ");
347 print_word_size_delta(&ls, committed_before, committed_after);
348 ls.cr();
349 }
350 }
351 DEBUG_ONLY(_vslist->verify_locked())_vslist->verify_locked();
352 DEBUG_ONLY(verify_locked())verify_locked();
353}
354
355// Convenience methods to return the global class-space chunkmanager
356// and non-class chunkmanager, respectively.
357ChunkManager* ChunkManager::chunkmanager_class() {
358 return MetaspaceContext::context_class() == NULL__null ? NULL__null : MetaspaceContext::context_class()->cm();
359}
360
361ChunkManager* ChunkManager::chunkmanager_nonclass() {
362 return MetaspaceContext::context_nonclass() == NULL__null ? NULL__null : MetaspaceContext::context_nonclass()->cm();
363}
364
365// Calculates the total number of committed words over all chunks. Walks chunks.
366size_t ChunkManager::calc_committed_word_size() const {
367 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
368 return calc_committed_word_size_locked();
369}
370
371size_t ChunkManager::calc_committed_word_size_locked() const {
372 assert_lock_strong(Metaspace_lock);
373 return _chunks.calc_committed_word_size();
374}
375
376// Update statistics.
377void ChunkManager::add_to_statistics(ChunkManagerStats* out) const {
378 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
379 for (chunklevel_t l = chunklevel::ROOT_CHUNK_LEVEL; l <= chunklevel::HIGHEST_CHUNK_LEVEL; l++) {
380 out->_num_chunks[l] += _chunks.num_chunks_at_level(l);
381 out->_committed_word_size[l] += _chunks.calc_committed_word_size_at_level(l);
382 }
383 DEBUG_ONLY(out->verify();)out->verify();
384}
385
386#ifdef ASSERT1
387
388void ChunkManager::verify() const {
389 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
390 verify_locked();
391}
392
393void ChunkManager::verify_locked() const {
394 assert_lock_strong(Metaspace_lock);
395 assert(_vslist != NULL, "No vslist")do { if (!(_vslist != __null)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/memory/metaspace/chunkManager.cpp"
, 395, "assert(" "_vslist != __null" ") failed", "No vslist")
; ::breakpoint(); } } while (0);
396 _chunks.verify();
397}
398
399bool ChunkManager::contains_chunk(Metachunk* c) const {
400 return _chunks.contains(c);
401}
402
403#endif // ASSERT
404
405void ChunkManager::print_on(outputStream* st) const {
406 MutexLocker fcl(Metaspace_lock, Mutex::_no_safepoint_check_flag);
407 print_on_locked(st);
408}
409
410void ChunkManager::print_on_locked(outputStream* st) const {
411 assert_lock_strong(Metaspace_lock);
412 st->print_cr("cm %s: %d chunks, total word size: " SIZE_FORMAT"%" "l" "u" ".", _name,
413 total_num_chunks(), total_word_size());
414 _chunks.print_on(st);
415}
416
417} // namespace metaspace