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 "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/heapMonitoring.hpp"
37 #include "runtime/sharedRuntime.hpp"
38 #include "runtime/thread.inline.hpp"
39 #include "services/lowMemoryDetector.hpp"
40 #include "utilities/copy.hpp"
41
42 // Inline allocation implementations.
43
44 void CollectedHeap::post_allocation_setup_common(KlassHandle 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(KlassHandle 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(KlassHandle 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 if (HeapMonitor) {
87 // support for object alloc event (no-op most of the time)
88 if (klass() != NULL && klass()->name() != NULL) {
89 Thread *base_thread = Thread::current();
90 if (base_thread->is_Java_thread()) {
91 JavaThread *thread = (JavaThread *) base_thread;
92 size_t *bytes_until_sample = thread->bytes_until_sample();
93 size_t size_in_bytes = ((size_t) size) << LogHeapWordSize;
94 assert(size > 0, "positive size");
95 if (*bytes_until_sample < size_in_bytes) {
96 HeapMonitoring::object_alloc_do_sample(thread, obj, size_in_bytes);
97 } else {
98 *bytes_until_sample -= size_in_bytes;
99 }
100 }
101 }
102 }
103 }
104
105 void CollectedHeap::post_allocation_setup_obj(KlassHandle klass,
106 HeapWord* obj_ptr,
107 int size) {
108 post_allocation_setup_common(klass, obj_ptr);
109 oop obj = (oop)obj_ptr;
110 assert(Universe::is_bootstrapping() ||
111 !obj->is_array(), "must not be an array");
112 // notify jvmti and dtrace
113 post_allocation_notify(klass, obj, size);
114 }
115
116 void CollectedHeap::post_allocation_setup_class(KlassHandle klass,
117 HeapWord* obj_ptr,
118 int size) {
119 // Set oop_size field before setting the _klass field because a
120 // non-NULL _klass field indicates that the object is parsable by
121 // concurrent GC.
122 oop new_cls = (oop)obj_ptr;
123 assert(size > 0, "oop_size must be positive.");
124 java_lang_Class::set_oop_size(new_cls, size);
125 post_allocation_setup_common(klass, obj_ptr);
126 assert(Universe::is_bootstrapping() ||
127 !new_cls->is_array(), "must not be an array");
128 // notify jvmti and dtrace
129 post_allocation_notify(klass, new_cls, size);
130 }
131
132 void CollectedHeap::post_allocation_setup_array(KlassHandle klass,
133 HeapWord* obj_ptr,
134 int length) {
135 // Set array length before setting the _klass field because a
136 // non-NULL klass field indicates that the object is parsable by
137 // concurrent GC.
138 assert(length >= 0, "length should be non-negative");
139 ((arrayOop)obj_ptr)->set_length(length);
140 post_allocation_setup_common(klass, obj_ptr);
141 oop new_obj = (oop)obj_ptr;
142 assert(new_obj->is_array(), "must be an array");
143 // notify jvmti and dtrace (must be after length is set for dtrace)
144 post_allocation_notify(klass, new_obj, new_obj->size());
145 }
146
147 HeapWord* CollectedHeap::common_mem_allocate_noinit(KlassHandle klass, size_t size, TRAPS) {
148
149 // Clear unhandled oops for memory allocation. Memory allocation might
150 // not take out a lock if from tlab, so clear here.
151 CHECK_UNHANDLED_OOPS_ONLY(THREAD->clear_unhandled_oops();)
152
153 if (HAS_PENDING_EXCEPTION) {
154 NOT_PRODUCT(guarantee(false, "Should not allocate with exception pending"));
155 return NULL; // caller does a CHECK_0 too
156 }
157
158 HeapWord* result = NULL;
159 if (UseTLAB) {
160 result = allocate_from_tlab(klass, THREAD, size);
161 if (result != NULL) {
162 assert(!HAS_PENDING_EXCEPTION,
163 "Unexpected exception, will result in uninitialized storage");
164 return result;
165 }
166 }
167 bool gc_overhead_limit_was_exceeded = false;
168 result = Universe::heap()->mem_allocate(size,
169 &gc_overhead_limit_was_exceeded);
170 if (result != NULL) {
171 NOT_PRODUCT(Universe::heap()->
172 check_for_non_bad_heap_word_value(result, size));
173 assert(!HAS_PENDING_EXCEPTION,
174 "Unexpected exception, will result in uninitialized storage");
175 THREAD->incr_allocated_bytes(size * HeapWordSize);
176
177 AllocTracer::send_allocation_outside_tlab_event(klass, size * HeapWordSize);
178
179 return result;
180 }
181
182
183 if (!gc_overhead_limit_was_exceeded) {
184 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
185 report_java_out_of_memory("Java heap space");
186
187 if (JvmtiExport::should_post_resource_exhausted()) {
188 JvmtiExport::post_resource_exhausted(
189 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
190 "Java heap space");
191 }
192
193 THROW_OOP_0(Universe::out_of_memory_error_java_heap());
194 } else {
195 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
196 report_java_out_of_memory("GC overhead limit exceeded");
197
198 if (JvmtiExport::should_post_resource_exhausted()) {
199 JvmtiExport::post_resource_exhausted(
200 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
201 "GC overhead limit exceeded");
202 }
203
204 THROW_OOP_0(Universe::out_of_memory_error_gc_overhead_limit());
205 }
206 }
207
208 HeapWord* CollectedHeap::common_mem_allocate_init(KlassHandle klass, size_t size, TRAPS) {
209 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
210 init_obj(obj, size);
211 return obj;
212 }
213
214 HeapWord* CollectedHeap::allocate_from_tlab(KlassHandle klass, Thread* thread, size_t size) {
215 assert(UseTLAB, "should use UseTLAB");
216
217 HeapWord* obj = thread->tlab().allocate(size);
218 if (obj != NULL) {
219 return obj;
220 }
221 // Otherwise...
222 return allocate_from_tlab_slow(klass, thread, size);
223 }
224
225 void CollectedHeap::init_obj(HeapWord* obj, size_t size) {
226 assert(obj != NULL, "cannot initialize NULL object");
227 const size_t hs = oopDesc::header_size();
228 assert(size >= hs, "unexpected object size");
229 ((oop)obj)->set_klass_gap(0);
230 Copy::fill_to_aligned_words(obj + hs, size - hs);
231 }
232
233 oop CollectedHeap::obj_allocate(KlassHandle klass, int size, TRAPS) {
234 debug_only(check_for_valid_allocation_state());
235 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
236 assert(size >= 0, "int won't convert to size_t");
237 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
238 post_allocation_setup_obj(klass, obj, size);
239 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
240 return (oop)obj;
241 }
242
243 oop CollectedHeap::class_allocate(KlassHandle klass, int size, 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_class(klass, obj, size); // set oop_size
249 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
250 return (oop)obj;
251 }
252
253 oop CollectedHeap::array_allocate(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_init(klass, size, CHECK_NULL);
261 post_allocation_setup_array(klass, obj, length);
262 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
263 return (oop)obj;
264 }
265
266 oop CollectedHeap::array_allocate_nozero(KlassHandle klass,
267 int size,
268 int length,
269 TRAPS) {
270 debug_only(check_for_valid_allocation_state());
271 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
272 assert(size >= 0, "int won't convert to size_t");
273 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
274 ((oop)obj)->set_klass_gap(0);
275 post_allocation_setup_array(klass, obj, length);
276 #ifndef PRODUCT
277 const size_t hs = oopDesc::header_size()+1;
278 Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs);
279 #endif
280 return (oop)obj;
281 }
282
283 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr,
284 HeapWord* end,
285 unsigned short alignment_in_bytes) {
286 if (alignment_in_bytes <= ObjectAlignmentInBytes) {
287 return addr;
288 }
289
290 assert(is_ptr_aligned(addr, HeapWordSize),
291 "Address " PTR_FORMAT " is not properly aligned.", p2i(addr));
292 assert(is_size_aligned(alignment_in_bytes, HeapWordSize),
293 "Alignment size %u is incorrect.", alignment_in_bytes);
294
295 HeapWord* new_addr = (HeapWord*) align_ptr_up(addr, alignment_in_bytes);
296 size_t padding = pointer_delta(new_addr, addr);
297
298 if (padding == 0) {
299 return addr;
300 }
301
302 if (padding < CollectedHeap::min_fill_size()) {
303 padding += alignment_in_bytes / HeapWordSize;
304 assert(padding >= CollectedHeap::min_fill_size(),
305 "alignment_in_bytes %u is expect to be larger "
306 "than the minimum object size", alignment_in_bytes);
307 new_addr = addr + padding;
308 }
309
310 assert(new_addr > addr, "Unexpected arithmetic overflow "
311 PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr));
312 if(new_addr < end) {
313 CollectedHeap::fill_with_object(addr, padding);
314 return new_addr;
315 } else {
316 return NULL;
317 }
318 }
319
320 #ifndef PRODUCT
321
322 inline bool
323 CollectedHeap::promotion_should_fail(volatile size_t* count) {
324 // Access to count is not atomic; the value does not have to be exact.
325 if (PromotionFailureALot) {
326 const size_t gc_num = total_collections();
327 const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number;
328 if (elapsed_gcs >= PromotionFailureALotInterval) {
329 // Test for unsigned arithmetic wrap-around.
330 if (++*count >= PromotionFailureALotCount) {
331 *count = 0;
332 return true;
333 }
334 }
335 }
336 return false;
337 }
338
339 inline bool CollectedHeap::promotion_should_fail() {
340 return promotion_should_fail(&_promotion_failure_alot_count);
341 }
342
343 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) {
344 if (PromotionFailureALot) {
345 _promotion_failure_alot_gc_number = total_collections();
346 *count = 0;
347 }
348 }
349
350 inline void CollectedHeap::reset_promotion_should_fail() {
351 reset_promotion_should_fail(&_promotion_failure_alot_count);
352 }
353 #endif // #ifndef PRODUCT
354
355 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP