1 /*
2 * Copyright (c) 2001, 2017, 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 #ifndef SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP
26 #define SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP
27
28 #include "classfile/javaClasses.hpp"
29 #include "gc/shared/allocTracer.hpp"
30 #include "gc/shared/collectedHeap.hpp"
31 #include "gc/shared/threadLocalAllocBuffer.inline.hpp"
32 #include "memory/universe.hpp"
33 #include "oops/arrayOop.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "prims/jvmtiExport.hpp"
36 #include "runtime/sharedRuntime.hpp"
37 #include "runtime/thread.inline.hpp"
38 #include "services/lowMemoryDetector.hpp"
39 #include "utilities/align.hpp"
40 #include "utilities/copy.hpp"
41
42 // Inline allocation implementations.
43
44 void CollectedHeap::post_allocation_setup_common(Klass* klass,
45 HeapWord* obj_ptr) {
46 post_allocation_setup_no_klass_install(klass, obj_ptr);
47 oop obj = (oop)obj_ptr;
48 #if ! INCLUDE_ALL_GCS
49 obj->set_klass(klass);
50 #else
51 // Need a release store to ensure array/class length, mark word, and
52 // object zeroing are visible before setting the klass non-NULL, for
53 // concurrent collectors.
54 obj->release_set_klass(klass);
55 #endif
56 }
57
58 void CollectedHeap::post_allocation_setup_no_klass_install(Klass* klass,
59 HeapWord* obj_ptr) {
60 oop obj = (oop)obj_ptr;
61
62 assert(obj != NULL, "NULL object pointer");
63 if (UseBiasedLocking && (klass != NULL)) {
64 obj->set_mark(klass->prototype_header());
65 } else {
66 // May be bootstrapping
67 obj->set_mark(markOopDesc::prototype());
68 }
69 }
70
71 // Support for jvmti and dtrace
72 inline void post_allocation_notify(Klass* klass, oop obj, int size) {
73 // support low memory notifications (no-op if not enabled)
74 LowMemoryDetector::detect_low_memory_for_collected_pools();
75
76 // support for JVMTI VMObjectAlloc event (no-op if not enabled)
77 JvmtiExport::vm_object_alloc_event_collector(obj);
78
79 if (DTraceAllocProbes) {
80 // support for Dtrace object alloc event (no-op most of the time)
81 if (klass != NULL && klass->name() != NULL) {
82 SharedRuntime::dtrace_object_alloc(obj, size);
83 }
84 }
85 }
86
87 void CollectedHeap::post_allocation_setup_obj(Klass* klass,
88 HeapWord* obj_ptr,
89 int size) {
90 post_allocation_setup_common(klass, obj_ptr);
91 oop obj = (oop)obj_ptr;
92 assert(Universe::is_bootstrapping() ||
93 !obj->is_array(), "must not be an array");
94 // notify jvmti and dtrace
95 post_allocation_notify(klass, obj, size);
96 }
97
98 void CollectedHeap::post_allocation_setup_class(Klass* klass,
99 HeapWord* obj_ptr,
100 int size) {
101 // Set oop_size field before setting the _klass field because a
102 // non-NULL _klass field indicates that the object is parsable by
103 // concurrent GC.
104 oop new_cls = (oop)obj_ptr;
105 assert(size > 0, "oop_size must be positive.");
106 java_lang_Class::set_oop_size(new_cls, size);
107 post_allocation_setup_common(klass, obj_ptr);
108 assert(Universe::is_bootstrapping() ||
109 !new_cls->is_array(), "must not be an array");
110 // notify jvmti and dtrace
111 post_allocation_notify(klass, new_cls, size);
112 }
113
114 void CollectedHeap::post_allocation_setup_array(Klass* klass,
115 HeapWord* obj_ptr,
116 int length) {
117 // Set array length before setting the _klass field because a
118 // non-NULL klass field indicates that the object is parsable by
119 // concurrent GC.
120 assert(length >= 0, "length should be non-negative");
121 ((arrayOop)obj_ptr)->set_length(length);
122 post_allocation_setup_common(klass, obj_ptr);
123 oop new_obj = (oop)obj_ptr;
124 assert(new_obj->is_array(), "must be an array");
125 // notify jvmti and dtrace (must be after length is set for dtrace)
126 post_allocation_notify(klass, new_obj, new_obj->size());
127 }
128
129 HeapWord* CollectedHeap::common_mem_allocate_noinit(Klass* klass, size_t size, TRAPS) {
130
131 // Clear unhandled oops for memory allocation. Memory allocation might
132 // not take out a lock if from tlab, so clear here.
133 CHECK_UNHANDLED_OOPS_ONLY(THREAD->clear_unhandled_oops();)
134
135 if (HAS_PENDING_EXCEPTION) {
136 NOT_PRODUCT(guarantee(false, "Should not allocate with exception pending"));
137 return NULL; // caller does a CHECK_0 too
138 }
139
140 HeapWord* result = NULL;
141 if (UseTLAB) {
142 result = allocate_from_tlab(klass, THREAD, size);
143 if (result != NULL) {
144 assert(!HAS_PENDING_EXCEPTION,
145 "Unexpected exception, will result in uninitialized storage");
146 return result;
147 }
148 }
149 bool gc_overhead_limit_was_exceeded = false;
150 result = Universe::heap()->mem_allocate(size,
151 &gc_overhead_limit_was_exceeded);
152 if (result != NULL) {
153 NOT_PRODUCT(Universe::heap()->
154 check_for_non_bad_heap_word_value(result, size));
155 assert(!HAS_PENDING_EXCEPTION,
156 "Unexpected exception, will result in uninitialized storage");
157 THREAD->incr_allocated_bytes(size * HeapWordSize);
158
159 AllocTracer::send_allocation_outside_tlab(klass, result, size * HeapWordSize, THREAD);
160
161 if (UseTLAB) {
162 THREAD->tlab().handle_sample(THREAD, result, size);
163 }
164 return result;
165 }
166
167
168 if (!gc_overhead_limit_was_exceeded) {
169 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
170 report_java_out_of_memory("Java heap space");
171
172 if (JvmtiExport::should_post_resource_exhausted()) {
173 JvmtiExport::post_resource_exhausted(
174 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
175 "Java heap space");
176 }
177
178 THROW_OOP_0(Universe::out_of_memory_error_java_heap());
179 } else {
180 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
181 report_java_out_of_memory("GC overhead limit exceeded");
182
183 if (JvmtiExport::should_post_resource_exhausted()) {
184 JvmtiExport::post_resource_exhausted(
185 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
186 "GC overhead limit exceeded");
187 }
188
189 THROW_OOP_0(Universe::out_of_memory_error_gc_overhead_limit());
190 }
191 }
192
193 HeapWord* CollectedHeap::common_mem_allocate_init(Klass* klass, size_t size, TRAPS) {
194 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
195 init_obj(obj, size);
196 return obj;
197 }
198
199 HeapWord* CollectedHeap::allocate_from_tlab(Klass* klass, Thread* thread, size_t size) {
200 assert(UseTLAB, "should use UseTLAB");
201
202 HeapWord* obj = thread->tlab().allocate(size);
203 if (obj != NULL) {
204 return obj;
205 }
206 // Otherwise...
207 return allocate_from_tlab_slow(klass, thread, size);
208 }
209
210 void CollectedHeap::init_obj(HeapWord* obj, size_t size) {
211 assert(obj != NULL, "cannot initialize NULL object");
212 const size_t hs = oopDesc::header_size();
213 assert(size >= hs, "unexpected object size");
214 ((oop)obj)->set_klass_gap(0);
215 Copy::fill_to_aligned_words(obj + hs, size - hs);
216 }
217
218 oop CollectedHeap::obj_allocate(Klass* klass, int size, TRAPS) {
219 debug_only(check_for_valid_allocation_state());
220 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
221 assert(size >= 0, "int won't convert to size_t");
222 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
223 post_allocation_setup_obj(klass, obj, size);
224 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
225 return (oop)obj;
226 }
227
228 oop CollectedHeap::class_allocate(Klass* klass, int size, TRAPS) {
229 debug_only(check_for_valid_allocation_state());
230 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
231 assert(size >= 0, "int won't convert to size_t");
232 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
233 post_allocation_setup_class(klass, obj, size); // set oop_size
234 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
235 return (oop)obj;
236 }
237
238 oop CollectedHeap::array_allocate(Klass* klass,
239 int size,
240 int length,
241 TRAPS) {
242 debug_only(check_for_valid_allocation_state());
243 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
244 assert(size >= 0, "int won't convert to size_t");
245 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
246 post_allocation_setup_array(klass, obj, length);
247 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
248 return (oop)obj;
249 }
250
251 oop CollectedHeap::array_allocate_nozero(Klass* klass,
252 int size,
253 int length,
254 TRAPS) {
255 debug_only(check_for_valid_allocation_state());
256 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
257 assert(size >= 0, "int won't convert to size_t");
258 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
259 ((oop)obj)->set_klass_gap(0);
260 post_allocation_setup_array(klass, obj, length);
261 #ifndef PRODUCT
262 const size_t hs = oopDesc::header_size()+1;
263 Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs);
264 #endif
265 return (oop)obj;
266 }
267
268 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr,
269 HeapWord* end,
270 unsigned short alignment_in_bytes) {
271 if (alignment_in_bytes <= ObjectAlignmentInBytes) {
272 return addr;
273 }
274
275 assert(is_aligned(addr, HeapWordSize),
276 "Address " PTR_FORMAT " is not properly aligned.", p2i(addr));
277 assert(is_aligned(alignment_in_bytes, HeapWordSize),
278 "Alignment size %u is incorrect.", alignment_in_bytes);
279
280 HeapWord* new_addr = align_up(addr, alignment_in_bytes);
281 size_t padding = pointer_delta(new_addr, addr);
282
283 if (padding == 0) {
284 return addr;
285 }
286
287 if (padding < CollectedHeap::min_fill_size()) {
288 padding += alignment_in_bytes / HeapWordSize;
289 assert(padding >= CollectedHeap::min_fill_size(),
290 "alignment_in_bytes %u is expect to be larger "
291 "than the minimum object size", alignment_in_bytes);
292 new_addr = addr + padding;
293 }
294
295 assert(new_addr > addr, "Unexpected arithmetic overflow "
296 PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr));
297 if(new_addr < end) {
298 CollectedHeap::fill_with_object(addr, padding);
299 return new_addr;
300 } else {
301 return NULL;
302 }
303 }
304
305 #ifndef PRODUCT
306
307 inline bool
308 CollectedHeap::promotion_should_fail(volatile size_t* count) {
309 // Access to count is not atomic; the value does not have to be exact.
310 if (PromotionFailureALot) {
311 const size_t gc_num = total_collections();
312 const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number;
313 if (elapsed_gcs >= PromotionFailureALotInterval) {
314 // Test for unsigned arithmetic wrap-around.
315 if (++*count >= PromotionFailureALotCount) {
316 *count = 0;
317 return true;
318 }
319 }
320 }
321 return false;
322 }
323
324 inline bool CollectedHeap::promotion_should_fail() {
325 return promotion_should_fail(&_promotion_failure_alot_count);
326 }
327
328 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) {
329 if (PromotionFailureALot) {
330 _promotion_failure_alot_gc_number = total_collections();
331 *count = 0;
332 }
333 }
334
335 inline void CollectedHeap::reset_promotion_should_fail() {
336 reset_promotion_should_fail(&_promotion_failure_alot_count);
337 }
338 #endif // #ifndef PRODUCT
339
340 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP