1 /*
2 * Copyright (c) 2001, 2015, 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 "prims/jvmtiExport.hpp"
34 #include "runtime/sharedRuntime.hpp"
35 #include "runtime/thread.inline.hpp"
36 #include "services/lowMemoryDetector.hpp"
37 #include "utilities/copy.hpp"
38
39 // Inline allocation implementations.
40
41 void CollectedHeap::post_allocation_setup_common(KlassHandle klass,
42 HeapWord* obj) {
43 post_allocation_setup_no_klass_install(klass, obj);
44 post_allocation_install_obj_klass(klass, oop(obj));
45 }
46
47 void CollectedHeap::post_allocation_setup_no_klass_install(KlassHandle klass,
48 HeapWord* objPtr) {
49 oop obj = (oop)objPtr;
50
51 assert(obj != NULL, "NULL object pointer");
52 if (UseBiasedLocking && (klass() != NULL)) {
53 obj->set_mark(klass->prototype_header());
54 } else {
55 // May be bootstrapping
56 obj->set_mark(markOopDesc::prototype());
57 }
58 }
59
60 void CollectedHeap::post_allocation_install_obj_klass(KlassHandle klass,
61 oop obj) {
62 // These asserts are kind of complicated because of klassKlass
63 // and the beginning of the world.
64 assert(klass() != NULL || !Universe::is_fully_initialized(), "NULL klass");
65 assert(klass() == NULL || klass()->is_klass(), "not a klass");
66 assert(obj != NULL, "NULL object pointer");
67 obj->set_klass(klass());
68 assert(!Universe::is_fully_initialized() || obj->klass() != NULL,
69 "missing klass");
70 }
71
72 // Support for jvmti and dtrace
73 inline void post_allocation_notify(KlassHandle klass, oop obj, int size) {
74 // support low memory notifications (no-op if not enabled)
75 LowMemoryDetector::detect_low_memory_for_collected_pools();
76
77 // support for JVMTI VMObjectAlloc event (no-op if not enabled)
78 JvmtiExport::vm_object_alloc_event_collector(obj);
79
80 if (DTraceAllocProbes) {
81 // support for Dtrace object alloc event (no-op most of the time)
82 if (klass() != NULL && klass()->name() != NULL) {
83 SharedRuntime::dtrace_object_alloc(obj, size);
84 }
85 }
86 }
87
88 void CollectedHeap::post_allocation_setup_obj(KlassHandle klass,
89 HeapWord* obj,
90 int size) {
91 post_allocation_setup_common(klass, obj);
92 assert(Universe::is_bootstrapping() ||
93 !((oop)obj)->is_array(), "must not be an array");
94 // notify jvmti and dtrace
95 post_allocation_notify(klass, (oop)obj, size);
96 }
97
98 void CollectedHeap::post_allocation_setup_array(KlassHandle klass,
99 HeapWord* obj,
100 int length) {
101 // Set array length before setting the _klass field
102 // in post_allocation_setup_common() because the klass field
103 // indicates that the object is parsable by concurrent GC.
104 assert(length >= 0, "length should be non-negative");
105 ((arrayOop)obj)->set_length(length);
106 post_allocation_setup_common(klass, obj);
107 oop new_obj = (oop)obj;
108 assert(new_obj->is_array(), "must be an array");
109 // notify jvmti and dtrace (must be after length is set for dtrace)
110 post_allocation_notify(klass, new_obj, new_obj->size());
111 }
112
113 HeapWord* CollectedHeap::common_mem_allocate_noinit(KlassHandle klass, size_t size, TRAPS) {
114
115 // Clear unhandled oops for memory allocation. Memory allocation might
116 // not take out a lock if from tlab, so clear here.
117 CHECK_UNHANDLED_OOPS_ONLY(THREAD->clear_unhandled_oops();)
118
119 if (HAS_PENDING_EXCEPTION) {
120 NOT_PRODUCT(guarantee(false, "Should not allocate with exception pending"));
121 return NULL; // caller does a CHECK_0 too
122 }
123
124 HeapWord* result = NULL;
125 if (UseTLAB) {
126 result = allocate_from_tlab(klass, THREAD, size);
127 if (result != NULL) {
128 assert(!HAS_PENDING_EXCEPTION,
129 "Unexpected exception, will result in uninitialized storage");
130 return result;
131 }
132 }
133 bool gc_overhead_limit_was_exceeded = false;
134 result = Universe::heap()->mem_allocate(size,
135 &gc_overhead_limit_was_exceeded);
136 if (result != NULL) {
137 NOT_PRODUCT(Universe::heap()->
138 check_for_non_bad_heap_word_value(result, size));
139 assert(!HAS_PENDING_EXCEPTION,
140 "Unexpected exception, will result in uninitialized storage");
141 THREAD->incr_allocated_bytes(size * HeapWordSize);
142
143 AllocTracer::send_allocation_outside_tlab_event(klass, size * HeapWordSize);
144
145 return result;
146 }
147
148
149 if (!gc_overhead_limit_was_exceeded) {
150 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
151 report_java_out_of_memory("Java heap space");
152
153 if (JvmtiExport::should_post_resource_exhausted()) {
154 JvmtiExport::post_resource_exhausted(
155 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
156 "Java heap space");
157 }
158
159 THROW_OOP_0(Universe::out_of_memory_error_java_heap());
160 } else {
161 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
162 report_java_out_of_memory("GC overhead limit exceeded");
163
164 if (JvmtiExport::should_post_resource_exhausted()) {
165 JvmtiExport::post_resource_exhausted(
166 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,
167 "GC overhead limit exceeded");
168 }
169
170 THROW_OOP_0(Universe::out_of_memory_error_gc_overhead_limit());
171 }
172 }
173
174 HeapWord* CollectedHeap::common_mem_allocate_init(KlassHandle klass, size_t size, TRAPS) {
175 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
176 init_obj(obj, size);
177 return obj;
178 }
179
180 HeapWord* CollectedHeap::allocate_from_tlab(KlassHandle klass, Thread* thread, size_t size) {
181 assert(UseTLAB, "should use UseTLAB");
182
183 size += Universe::heap()->oop_extra_words();
184 HeapWord* obj = thread->tlab().allocate(size);
185 if (obj != NULL) {
186 obj = Universe::heap()->tlab_post_allocation_setup(obj);
187 return obj;
188 }
189 // Otherwise...
190 return allocate_from_tlab_slow(klass, thread, size);
191 }
192
193 void CollectedHeap::init_obj(HeapWord* obj, size_t size) {
194 assert(obj != NULL, "cannot initialize NULL object");
195 const size_t hs = oopDesc::header_size();
196 assert(size >= hs, "unexpected object size");
197 ((oop)obj)->set_klass_gap(0);
198 Copy::fill_to_aligned_words(obj + hs, size - hs);
199 }
200
201 oop CollectedHeap::obj_allocate(KlassHandle klass, int size, TRAPS) {
202 debug_only(check_for_valid_allocation_state());
203 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
204 assert(size >= 0, "int won't convert to size_t");
205 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
206 post_allocation_setup_obj(klass, obj, size);
207 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
208 return (oop)obj;
209 }
210
211 oop CollectedHeap::array_allocate(KlassHandle klass,
212 int size,
213 int length,
214 TRAPS) {
215 debug_only(check_for_valid_allocation_state());
216 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
217 assert(size >= 0, "int won't convert to size_t");
218 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);
219 post_allocation_setup_array(klass, obj, length);
220 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
221 return (oop)obj;
222 }
223
224 oop CollectedHeap::array_allocate_nozero(KlassHandle klass,
225 int size,
226 int length,
227 TRAPS) {
228 debug_only(check_for_valid_allocation_state());
229 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
230 assert(size >= 0, "int won't convert to size_t");
231 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);
232 ((oop)obj)->set_klass_gap(0);
233 post_allocation_setup_array(klass, obj, length);
234 #ifndef PRODUCT
235 const size_t hs = oopDesc::header_size()+1;
236 Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs);
237 #endif
238 return (oop)obj;
239 }
240
241 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr,
242 HeapWord* end,
243 unsigned short alignment_in_bytes) {
244 if (alignment_in_bytes <= ObjectAlignmentInBytes) {
245 return addr;
246 }
247
248 assert(is_ptr_aligned(addr, HeapWordSize),
249 err_msg("Address " PTR_FORMAT " is not properly aligned.", p2i(addr)));
250 assert(is_size_aligned(alignment_in_bytes, HeapWordSize),
251 err_msg("Alignment size %u is incorrect.", alignment_in_bytes));
252
253 HeapWord* new_addr = (HeapWord*) align_pointer_up(addr, alignment_in_bytes);
254 size_t padding = pointer_delta(new_addr, addr);
255
256 if (padding == 0) {
257 return addr;
258 }
259
260 if (padding < CollectedHeap::min_fill_size()) {
261 padding += alignment_in_bytes / HeapWordSize;
262 assert(padding >= CollectedHeap::min_fill_size(),
263 err_msg("alignment_in_bytes %u is expect to be larger "
264 "than the minimum object size", alignment_in_bytes));
265 new_addr = addr + padding;
266 }
267
268 assert(new_addr > addr, err_msg("Unexpected arithmetic overflow "
269 PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr)));
270 if(new_addr < end) {
271 CollectedHeap::fill_with_object(addr, padding);
272 return new_addr;
273 } else {
274 return NULL;
275 }
276 }
277
278 #ifndef PRODUCT
279
280 inline bool
281 CollectedHeap::promotion_should_fail(volatile size_t* count) {
282 // Access to count is not atomic; the value does not have to be exact.
283 if (PromotionFailureALot) {
284 const size_t gc_num = total_collections();
285 const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number;
286 if (elapsed_gcs >= PromotionFailureALotInterval) {
287 // Test for unsigned arithmetic wrap-around.
288 if (++*count >= PromotionFailureALotCount) {
289 *count = 0;
290 return true;
291 }
292 }
293 }
294 return false;
295 }
296
297 inline bool CollectedHeap::promotion_should_fail() {
298 return promotion_should_fail(&_promotion_failure_alot_count);
299 }
300
301 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) {
302 if (PromotionFailureALot) {
303 _promotion_failure_alot_gc_number = total_collections();
304 *count = 0;
305 }
306 }
307
308 inline void CollectedHeap::reset_promotion_should_fail() {
309 reset_promotion_should_fail(&_promotion_failure_alot_count);
310 }
311 #endif // #ifndef PRODUCT
312
313 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP