1 /*
2 * Copyright (c) 2001, 2016, 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 "gc/shared/allocTracer.hpp"
29 #include "gc/shared/collectedHeap.hpp"
30 #include "gc/shared/threadLocalAllocBuffer.inline.hpp"
31 #include "memory/universe.hpp"
32 #include "oops/arrayOop.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "prims/jvmtiExport.hpp"
35 #include "runtime/sharedRuntime.hpp"
36 #include "runtime/thread.inline.hpp"
37 #include "services/lowMemoryDetector.hpp"
38 #include "utilities/copy.hpp"
39
40 // Inline allocation implementations.
41
42 void CollectedHeap::post_allocation_setup_common(KlassHandle klass,
43 HeapWord* obj) {
44 post_allocation_setup_no_klass_install(klass, obj);
45 post_allocation_install_obj_klass(klass, oop(obj));
46 }
47
48 void CollectedHeap::post_allocation_setup_no_klass_install(KlassHandle klass,
49 HeapWord* objPtr) {
50 oop obj = (oop)objPtr;
51
52 assert(obj != NULL, "NULL object pointer");
53 if (UseBiasedLocking && (klass() != NULL)) {
54 obj->set_mark(klass->prototype_header());
55 } else {
56 // May be bootstrapping
57 obj->set_mark(markOopDesc::prototype());
58 }
59 }
60
61 void CollectedHeap::post_allocation_install_obj_klass(KlassHandle klass,
62 oop obj) {
63 // These asserts are kind of complicated because of klassKlass
64 // and the beginning of the world.
65 assert(klass() != NULL || !Universe::is_fully_initialized(), "NULL klass");
66 assert(klass() == NULL || klass()->is_klass(), "not a klass");
67 assert(obj != NULL, "NULL object pointer");
68 obj->set_klass(klass());
69 assert(!Universe::is_fully_initialized() || obj->klass() != NULL,
70 "missing klass");
71 }
72
73 // Support for jvmti and dtrace
74 inline void post_allocation_notify(KlassHandle klass, oop obj, int size) {
75 // support low memory notifications (no-op if not enabled)
76 LowMemoryDetector::detect_low_memory_for_collected_pools();
77
78 // support for JVMTI VMObjectAlloc event (no-op if not enabled)
79 JvmtiExport::vm_object_alloc_event_collector(obj);
80
81 if (DTraceAllocProbes) {
82 // support for Dtrace object alloc event (no-op most of the time)
83 if (klass() != NULL && klass()->name() != NULL) {
84 SharedRuntime::dtrace_object_alloc(obj, size);
85 }
86 }
87 }
88
89 void CollectedHeap::post_allocation_setup_obj(KlassHandle klass,
90 HeapWord* obj,
91 int size) {
92 post_allocation_setup_common(klass, obj);
93 assert(Universe::is_bootstrapping() ||
94 !((oop)obj)->is_array(), "must not be an array");
95 // notify jvmti and dtrace
96 post_allocation_notify(klass, (oop)obj, size);
97 }
98
99 void CollectedHeap::post_allocation_setup_class(KlassHandle klass,
100 HeapWord* obj,
101 int size,
102 int size_field_offset) {
103 post_allocation_setup_no_klass_install(klass, obj);
104
105 // set the j.l.Class instance's oop_size field BEFORE setting the header:
106 ((oop)obj)->int_field_put(size_field_offset, size);
107
108 post_allocation_install_obj_klass(klass, oop(obj)); // set the header
109 assert(Universe::is_bootstrapping() ||
110 !((oop)obj)->is_array(), "must not be an array");
111 // notify jvmti and dtrace
112 post_allocation_notify(klass, (oop)obj, size);
113 }
114
115 void CollectedHeap::post_allocation_setup_array(KlassHandle klass,
116 HeapWord* obj,
117 int length) {
118 // Set array length before setting the _klass field
119 // in post_allocation_setup_common() because the klass field
120 // indicates that the object is parsable by concurrent GC.
121 assert(length >= 0, "length should be non-negative");
122 ((arrayOop)obj)->set_length(length);
123 post_allocation_setup_common(klass, obj);
124 oop new_obj = (oop)obj;
125 assert(new_obj->is_array(), "must be an array");
126 // notify jvmti and dtrace (must be after length is set for dtrace)
127 post_allocation_notify(klass, new_obj, new_obj->size());
128 }
129
130 HeapWord* CollectedHeap::common_mem_allocate_noinit(KlassHandle klass, size_t size, TRAPS) {
131
132 // Clear unhandled oops for memory allocation. Memory allocation might
133 // not take out a lock if from tlab, so clear here.
134 CHECK_UNHANDLED_OOPS_ONLY(THREAD->clear_unhandled_oops();)
135
136 if (HAS_PENDING_EXCEPTION) {
137 NOT_PRODUCT(guarantee(false, "Should not allocate with exception pending"));
138 return NULL; // caller does a CHECK_0 too
139 }
140
141 HeapWord* result = NULL;
142 if (UseTLAB) {
143 result = allocate_from_tlab(klass, THREAD, size);
144 if (result != NULL) {
145 assert(!HAS_PENDING_EXCEPTION,
146 "Unexpected exception, will result in uninitialized storage");
147 return result;
148 }
149 }
150 bool gc_overhead_limit_was_exceeded = false;
151 result = Universe::heap()->mem_allocate(size,
152 &gc_overhead_limit_was_exceeded);
153 if (result != NULL) {
154 NOT_PRODUCT(Universe::heap()->
155 check_for_non_bad_heap_word_value(result, size));
156 assert(!HAS_PENDING_EXCEPTION,
157 "Unexpected exception, will result in uninitialized storage");
158 THREAD->incr_allocated_bytes(size * HeapWordSize);
159
160 AllocTracer::send_allocation_outside_tlab_event(klass, size * HeapWordSize);
161
162 return result;
163 }
164
165
166 if (!gc_overhead_limit_was_exceeded) {
167 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
168 report_java_out_of_memory("Java heap space");
169
170 if (JvmtiExport::should_post_resource_exhausted()) {
171 JvmtiExport::post_resource_exhausted(
172 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
173 "Java heap space");
174 }
175
176 THROW_OOP_0(Universe::out_of_memory_error_java_heap());
177 } else {
178 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
179 report_java_out_of_memory("GC overhead limit exceeded");
180
181 if (JvmtiExport::should_post_resource_exhausted()) {
182 JvmtiExport::post_resource_exhausted(
183 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
184 "GC overhead limit exceeded");
185 }
186
187 THROW_OOP_0(Universe::out_of_memory_error_gc_overhead_limit());
188 }
189 }
190
191 HeapWord* CollectedHeap::common_mem_allocate_init(KlassHandle klass, size_t size, TRAPS) {
192 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
193 init_obj(obj, size);
194 return obj;
195 }
196
197 HeapWord* CollectedHeap::allocate_from_tlab(KlassHandle klass, Thread* thread, size_t size) {
198 assert(UseTLAB, "should use UseTLAB");
199
200 HeapWord* obj = thread->tlab().allocate(size);
201 if (obj != NULL) {
202 return obj;
203 }
204 // Otherwise...
205 return allocate_from_tlab_slow(klass, thread, size);
206 }
207
208 void CollectedHeap::init_obj(HeapWord* obj, size_t size) {
209 assert(obj != NULL, "cannot initialize NULL object");
210 const size_t hs = oopDesc::header_size();
211 assert(size >= hs, "unexpected object size");
212 ((oop)obj)->set_klass_gap(0);
213 Copy::fill_to_aligned_words(obj + hs, size - hs);
214 }
215
216 oop CollectedHeap::obj_allocate(KlassHandle klass, int size, TRAPS) {
217 debug_only(check_for_valid_allocation_state());
218 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
219 assert(size >= 0, "int won't convert to size_t");
220 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
221 post_allocation_setup_obj(klass, obj, size);
222 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
223 return (oop)obj;
224 }
225
226 // Instances of j.l.Class have an oop_size field that must be set before the
227 // the header is set in order to parse the instances's size correctly.
228 oop CollectedHeap::class_allocate(KlassHandle klass, int size, int size_field_offset, 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, size_field_offset); // 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(KlassHandle 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(KlassHandle 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_ptr_aligned(addr, HeapWordSize),
276 "Address " PTR_FORMAT " is not properly aligned.", p2i(addr));
277 assert(is_size_aligned(alignment_in_bytes, HeapWordSize),
278 "Alignment size %u is incorrect.", alignment_in_bytes);
279
280 HeapWord* new_addr = (HeapWord*) align_ptr_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