1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
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).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "memory/allocation.hpp"
27 #include "memory/allocation.inline.hpp"
28 #include "memory/arena.hpp"
29 #include "memory/metaspace.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "nmt/memTracker.hpp"
32 #include "runtime/os.hpp"
33 #include "runtime/task.hpp"
34 #include "runtime/threadCritical.hpp"
35 #include "utilities/ostream.hpp"
36
37 // allocate using malloc; will fail if no memory available
38 char* AllocateHeap(size_t size,
39 MEMFLAGS flags,
40 const NativeCallStack& stack,
41 AllocFailType alloc_failmode /* = AllocFailStrategy::EXIT_OOM*/) {
42 char* p = (char*) os::malloc(size, flags, stack);
43 if (p == nullptr && alloc_failmode == AllocFailStrategy::EXIT_OOM) {
44 vm_exit_out_of_memory(size, OOM_MALLOC_ERROR, "AllocateHeap");
45 }
46 return p;
47 }
48
49 char* AllocateHeap(size_t size,
50 MEMFLAGS flags,
51 AllocFailType alloc_failmode /* = AllocFailStrategy::EXIT_OOM*/) {
52 return AllocateHeap(size, flags, CALLER_PC, alloc_failmode);
53 }
54
55 char* ReallocateHeap(char *old,
56 size_t size,
57 MEMFLAGS flag,
58 AllocFailType alloc_failmode) {
59 char* p = (char*) os::realloc(old, size, flag, CALLER_PC);
60 if (p == nullptr && alloc_failmode == AllocFailStrategy::EXIT_OOM) {
61 vm_exit_out_of_memory(size, OOM_MALLOC_ERROR, "ReallocateHeap");
62 }
63 return p;
64 }
65
66 // handles null pointers
67 void FreeHeap(void* p) {
68 os::free(p);
69 }
70
71 void* MetaspaceObj::_shared_metaspace_base = nullptr;
72 void* MetaspaceObj::_shared_metaspace_top = nullptr;
73
74 void* MetaspaceObj::operator new(size_t size, ClassLoaderData* loader_data,
75 size_t word_size,
76 MetaspaceObj::Type type, TRAPS) throw() {
77 // Klass has its own operator new
78 return Metaspace::allocate(loader_data, word_size, type, THREAD);
79 }
80
81 void* MetaspaceObj::operator new(size_t size, ClassLoaderData* loader_data,
82 size_t word_size,
83 MetaspaceObj::Type type) throw() {
84 assert(!Thread::current()->is_Java_thread(), "only allowed by non-Java thread");
85 return Metaspace::allocate(loader_data, word_size, type);
86 }
87
88 bool MetaspaceObj::is_valid(const MetaspaceObj* p) {
89 // Weed out obvious bogus values first without traversing metaspace
90 if ((size_t)p < os::min_page_size()) {
91 return false;
92 } else if (!is_aligned((address)p, sizeof(MetaWord))) {
93 return false;
94 }
95 return Metaspace::contains((void*)p);
96 }
97
98 void MetaspaceObj::print_address_on(outputStream* st) const {
99 st->print(" {" PTR_FORMAT "}", p2i(this));
100 }
101
102 //
103 // ArenaObj
104 //
105
106 void* ArenaObj::operator new(size_t size, Arena *arena) throw() {
107 return arena->Amalloc(size);
108 }
109
110 //
111 // AnyObj
112 //
113
114 void* AnyObj::operator new(size_t size, Arena *arena) {
115 address res = (address)arena->Amalloc(size);
116 DEBUG_ONLY(set_allocation_type(res, ARENA);)
117 return res;
118 }
119
120 void* AnyObj::operator new(size_t size, MEMFLAGS flags) throw() {
121 address res = (address)AllocateHeap(size, flags, CALLER_PC);
122 DEBUG_ONLY(set_allocation_type(res, C_HEAP);)
123 return res;
124 }
125
126 void* AnyObj::operator new(size_t size, const std::nothrow_t& nothrow_constant,
127 MEMFLAGS flags) throw() {
128 // should only call this with std::nothrow, use other operator new() otherwise
129 address res = (address)AllocateHeap(size, flags, CALLER_PC, AllocFailStrategy::RETURN_NULL);
130 DEBUG_ONLY(if (res!= nullptr) set_allocation_type(res, C_HEAP);)
131 return res;
132 }
133
134 void AnyObj::operator delete(void* p) {
135 if (p == nullptr) {
136 return;
137 }
138 assert(((AnyObj *)p)->allocated_on_C_heap(),
139 "delete only allowed for C_HEAP objects");
140 DEBUG_ONLY(((AnyObj *)p)->_allocation_t[0] = (uintptr_t)badHeapOopVal;)
141 FreeHeap(p);
142 }
143
144 #ifdef ASSERT
145 void AnyObj::set_allocation_type(address res, allocation_type type) {
146 // Set allocation type in the resource object
147 uintptr_t allocation = (uintptr_t)res;
148 assert((allocation & allocation_mask) == 0, "address should be aligned to 4 bytes at least: " PTR_FORMAT, p2i(res));
149 assert(type <= allocation_mask, "incorrect allocation type");
150 AnyObj* resobj = (AnyObj *)res;
151 resobj->_allocation_t[0] = ~(allocation + type);
152 if (type != STACK_OR_EMBEDDED) {
153 // Called from operator new(), set verification value.
154 resobj->_allocation_t[1] = (uintptr_t)&(resobj->_allocation_t[1]) + type;
155 }
156 }
157
158 AnyObj::allocation_type AnyObj::get_allocation_type() const {
159 assert(~(_allocation_t[0] | allocation_mask) == (uintptr_t)this, "lost resource object");
160 return (allocation_type)((~_allocation_t[0]) & allocation_mask);
161 }
162
163 bool AnyObj::is_type_set() const {
164 allocation_type type = (allocation_type)(_allocation_t[1] & allocation_mask);
165 return get_allocation_type() == type &&
166 (_allocation_t[1] - type) == (uintptr_t)(&_allocation_t[1]);
167 }
168
169 // This whole business of passing information from AnyObj::operator new
170 // to the AnyObj constructor via fields in the "object" is technically UB.
171 // But it seems to work within the limitations of HotSpot usage (such as no
172 // multiple inheritance) with the compilers and compiler options we're using.
173 // And it gives some possibly useful checking for misuse of AnyObj.
174 void AnyObj::initialize_allocation_info() {
175 if (~(_allocation_t[0] | allocation_mask) != (uintptr_t)this) {
176 // Operator new() is not called for allocations
177 // on stack and for embedded objects.
178 set_allocation_type((address)this, STACK_OR_EMBEDDED);
179 } else if (allocated_on_stack_or_embedded()) { // STACK_OR_EMBEDDED
180 // For some reason we got a value which resembles
181 // an embedded or stack object (operator new() does not
182 // set such type). Keep it since it is valid value
183 // (even if it was garbage).
184 // Ignore garbage in other fields.
185 } else if (is_type_set()) {
186 // Operator new() was called and type was set.
187 assert(!allocated_on_stack_or_embedded(),
188 "not embedded or stack, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
189 p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]);
190 } else {
191 // Operator new() was not called.
192 // Assume that it is embedded or stack object.
193 set_allocation_type((address)this, STACK_OR_EMBEDDED);
194 }
195 _allocation_t[1] = 0; // Zap verification value
196 }
197
198 AnyObj::AnyObj() {
199 initialize_allocation_info();
200 }
201
202 AnyObj::AnyObj(const AnyObj&) {
203 // Initialize _allocation_t as a new object, ignoring object being copied.
204 initialize_allocation_info();
205 }
206
207 AnyObj& AnyObj::operator=(const AnyObj& r) {
208 assert(allocated_on_stack_or_embedded(),
209 "copy only into local, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
210 p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]);
211 // Keep current _allocation_t value;
212 return *this;
213 }
214
215 AnyObj::~AnyObj() {
216 // allocated_on_C_heap() also checks that encoded (in _allocation) address == this.
217 if (!allocated_on_C_heap()) { // AnyObj::delete() will zap _allocation for C_heap.
218 _allocation_t[0] = (uintptr_t)badHeapOopVal; // zap type
219 }
220 }
221 #endif // ASSERT
222
223 //--------------------------------------------------------------------------------------
224 // Non-product code
225
226 #ifndef PRODUCT
227 void AnyObj::print() const { print_on(tty); }
228
229 void AnyObj::print_on(outputStream* st) const {
230 st->print_cr("AnyObj(" PTR_FORMAT ")", p2i(this));
231 }
232
233 ReallocMark::ReallocMark() {
234 #ifdef ASSERT
235 Thread *thread = Thread::current();
236 _nesting = thread->resource_area()->nesting();
237 #endif
238 }
239
240 void ReallocMark::check() {
241 #ifdef ASSERT
242 if (_nesting != Thread::current()->resource_area()->nesting()) {
243 fatal("allocation bug: array could grow within nested ResourceMark");
244 }
245 #endif
246 }
247
248 #endif // Non-product