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 // Set oop_size field before setting the _klass field
104 // in post_allocation_setup_common() because the klass field
105 // indicates that the object is parsable by concurrent GC.
106 oop new_obj = (oop)obj;
107 assert(size > 0, "oop_size must be positive.");
108 assert(size_field_offset > 0, "size_field_offset must be initialized.");
109 new_obj->int_field_put(size_field_offset, size);
110 post_allocation_setup_common(klass, obj);
111 assert(Universe::is_bootstrapping() ||
112 !new_obj->is_array(), "must not be an array");
113 // notify jvmti and dtrace
114 post_allocation_notify(klass, new_obj, size);
115 }
116
117 void CollectedHeap::post_allocation_setup_array(KlassHandle klass,
118 HeapWord* obj,
119 int length) {
120 // Set array length before setting the _klass field
121 // in post_allocation_setup_common() because the klass field
122 // indicates that the object is parsable by concurrent GC.
123 assert(length >= 0, "length should be non-negative");
124 ((arrayOop)obj)->set_length(length);
125 post_allocation_setup_common(klass, obj);
126 oop new_obj = (oop)obj;
127 assert(new_obj->is_array(), "must be an array");
128 // notify jvmti and dtrace (must be after length is set for dtrace)
129 post_allocation_notify(klass, new_obj, new_obj->size());
130 }
131
132 HeapWord* CollectedHeap::common_mem_allocate_noinit(KlassHandle klass, size_t size, TRAPS) {
133
134 // Clear unhandled oops for memory allocation. Memory allocation might
135 // not take out a lock if from tlab, so clear here.
136 CHECK_UNHANDLED_OOPS_ONLY(THREAD->clear_unhandled_oops();)
137
138 if (HAS_PENDING_EXCEPTION) {
139 NOT_PRODUCT(guarantee(false, "Should not allocate with exception pending"));
140 return NULL; // caller does a CHECK_0 too
141 }
142
143 HeapWord* result = NULL;
144 if (UseTLAB) {
145 result = allocate_from_tlab(klass, THREAD, size);
146 if (result != NULL) {
147 assert(!HAS_PENDING_EXCEPTION,
148 "Unexpected exception, will result in uninitialized storage");
149 return result;
150 }
151 }
152 bool gc_overhead_limit_was_exceeded = false;
153 result = Universe::heap()->mem_allocate(size,
154 &gc_overhead_limit_was_exceeded);
155 if (result != NULL) {
156 NOT_PRODUCT(Universe::heap()->
157 check_for_non_bad_heap_word_value(result, size));
158 assert(!HAS_PENDING_EXCEPTION,
159 "Unexpected exception, will result in uninitialized storage");
160 THREAD->incr_allocated_bytes(size * HeapWordSize);
161
162 AllocTracer::send_allocation_outside_tlab_event(klass, size * HeapWordSize);
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(KlassHandle 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(KlassHandle 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(KlassHandle 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 // Instances of j.l.Class have an oop_size field that must be set before the
229 // the header is set in order to parse the instances's size correctly.
230 oop CollectedHeap::class_allocate(KlassHandle klass, int size, int size_field_offset, TRAPS) {
231 debug_only(check_for_valid_allocation_state());
232 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
233 assert(size >= 0, "int won't convert to size_t");
234 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
235 post_allocation_setup_class(klass, obj, size, size_field_offset); // set oop_size
236 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
237 return (oop)obj;
238 }
239
240 oop CollectedHeap::array_allocate(KlassHandle klass,
241 int size,
242 int length,
243 TRAPS) {
244 debug_only(check_for_valid_allocation_state());
245 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
246 assert(size >= 0, "int won't convert to size_t");
247 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
248 post_allocation_setup_array(klass, obj, length);
249 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
250 return (oop)obj;
251 }
252
253 oop CollectedHeap::array_allocate_nozero(KlassHandle klass,
254 int size,
255 int length,
256 TRAPS) {
257 debug_only(check_for_valid_allocation_state());
258 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
259 assert(size >= 0, "int won't convert to size_t");
260 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
261 ((oop)obj)->set_klass_gap(0);
262 post_allocation_setup_array(klass, obj, length);
263 #ifndef PRODUCT
264 const size_t hs = oopDesc::header_size()+1;
265 Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs);
266 #endif
267 return (oop)obj;
268 }
269
270 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr,
271 HeapWord* end,
272 unsigned short alignment_in_bytes) {
273 if (alignment_in_bytes <= ObjectAlignmentInBytes) {
274 return addr;
275 }
276
277 assert(is_ptr_aligned(addr, HeapWordSize),
278 "Address " PTR_FORMAT " is not properly aligned.", p2i(addr));
279 assert(is_size_aligned(alignment_in_bytes, HeapWordSize),
280 "Alignment size %u is incorrect.", alignment_in_bytes);
281
282 HeapWord* new_addr = (HeapWord*) align_ptr_up(addr, alignment_in_bytes);
283 size_t padding = pointer_delta(new_addr, addr);
284
285 if (padding == 0) {
286 return addr;
287 }
288
289 if (padding < CollectedHeap::min_fill_size()) {
290 padding += alignment_in_bytes / HeapWordSize;
291 assert(padding >= CollectedHeap::min_fill_size(),
292 "alignment_in_bytes %u is expect to be larger "
293 "than the minimum object size", alignment_in_bytes);
294 new_addr = addr + padding;
295 }
296
297 assert(new_addr > addr, "Unexpected arithmetic overflow "
298 PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr));
299 if(new_addr < end) {
300 CollectedHeap::fill_with_object(addr, padding);
301 return new_addr;
302 } else {
303 return NULL;
304 }
305 }
306
307 #ifndef PRODUCT
308
309 inline bool
310 CollectedHeap::promotion_should_fail(volatile size_t* count) {
311 // Access to count is not atomic; the value does not have to be exact.
312 if (PromotionFailureALot) {
313 const size_t gc_num = total_collections();
314 const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number;
315 if (elapsed_gcs >= PromotionFailureALotInterval) {
316 // Test for unsigned arithmetic wrap-around.
317 if (++*count >= PromotionFailureALotCount) {
318 *count = 0;
319 return true;
320 }
321 }
322 }
323 return false;
324 }
325
326 inline bool CollectedHeap::promotion_should_fail() {
327 return promotion_should_fail(&_promotion_failure_alot_count);
328 }
329
330 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) {
331 if (PromotionFailureALot) {
332 _promotion_failure_alot_gc_number = total_collections();
333 *count = 0;
334 }
335 }
336
337 inline void CollectedHeap::reset_promotion_should_fail() {
338 reset_promotion_should_fail(&_promotion_failure_alot_count);
339 }
340 #endif // #ifndef PRODUCT
341
342 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP