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_event(klass, size * HeapWordSize); 160 161 THREAD->tlab().handle_sample(THREAD, result, size); 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(Klass* 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(Klass* 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(Klass* 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 oop CollectedHeap::class_allocate(Klass* klass, int size, TRAPS) { 227 debug_only(check_for_valid_allocation_state()); 228 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed"); 229 assert(size >= 0, "int won't convert to size_t"); 230 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL); 231 post_allocation_setup_class(klass, obj, size); // set oop_size 232 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size)); 233 return (oop)obj; 234 } 235 236 oop CollectedHeap::array_allocate(Klass* klass, 237 int size, 238 int length, 239 TRAPS) { 240 debug_only(check_for_valid_allocation_state()); 241 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed"); 242 assert(size >= 0, "int won't convert to size_t"); 243 HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL); 244 post_allocation_setup_array(klass, obj, length); 245 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size)); 246 return (oop)obj; 247 } 248 249 oop CollectedHeap::array_allocate_nozero(Klass* klass, 250 int size, 251 int length, 252 TRAPS) { 253 debug_only(check_for_valid_allocation_state()); 254 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed"); 255 assert(size >= 0, "int won't convert to size_t"); 256 HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL); 257 ((oop)obj)->set_klass_gap(0); 258 post_allocation_setup_array(klass, obj, length); 259 #ifndef PRODUCT 260 const size_t hs = oopDesc::header_size()+1; 261 Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs); 262 #endif 263 return (oop)obj; 264 } 265 266 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr, 267 HeapWord* end, 268 unsigned short alignment_in_bytes) { 269 if (alignment_in_bytes <= ObjectAlignmentInBytes) { 270 return addr; 271 } 272 273 assert(is_aligned(addr, HeapWordSize), 274 "Address " PTR_FORMAT " is not properly aligned.", p2i(addr)); 275 assert(is_aligned(alignment_in_bytes, HeapWordSize), 276 "Alignment size %u is incorrect.", alignment_in_bytes); 277 278 HeapWord* new_addr = align_up(addr, alignment_in_bytes); 279 size_t padding = pointer_delta(new_addr, addr); 280 281 if (padding == 0) { 282 return addr; 283 } 284 285 if (padding < CollectedHeap::min_fill_size()) { 286 padding += alignment_in_bytes / HeapWordSize; 287 assert(padding >= CollectedHeap::min_fill_size(), 288 "alignment_in_bytes %u is expect to be larger " 289 "than the minimum object size", alignment_in_bytes); 290 new_addr = addr + padding; 291 } 292 293 assert(new_addr > addr, "Unexpected arithmetic overflow " 294 PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr)); 295 if(new_addr < end) { 296 CollectedHeap::fill_with_object(addr, padding); 297 return new_addr; 298 } else { 299 return NULL; 300 } 301 } 302 303 #ifndef PRODUCT 304 305 inline bool 306 CollectedHeap::promotion_should_fail(volatile size_t* count) { 307 // Access to count is not atomic; the value does not have to be exact. 308 if (PromotionFailureALot) { 309 const size_t gc_num = total_collections(); 310 const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number; 311 if (elapsed_gcs >= PromotionFailureALotInterval) { 312 // Test for unsigned arithmetic wrap-around. 313 if (++*count >= PromotionFailureALotCount) { 314 *count = 0; 315 return true; 316 } 317 } 318 } 319 return false; 320 } 321 322 inline bool CollectedHeap::promotion_should_fail() { 323 return promotion_should_fail(&_promotion_failure_alot_count); 324 } 325 326 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) { 327 if (PromotionFailureALot) { 328 _promotion_failure_alot_gc_number = total_collections(); 329 *count = 0; 330 } 331 } 332 333 inline void CollectedHeap::reset_promotion_should_fail() { 334 reset_promotion_should_fail(&_promotion_failure_alot_count); 335 } 336 #endif // #ifndef PRODUCT 337 338 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP