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     return result;

   162   }

   163 

   164 

   165   if (!gc_overhead_limit_was_exceeded) {

   166     // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support

   167     report_java_out_of_memory("Java heap space");

   168 

   169     if (JvmtiExport::should_post_resource_exhausted()) {

   170       JvmtiExport::post_resource_exhausted(

   171         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,

   172         "Java heap space");

   173     }

   174 

   175     THROW_OOP_0(Universe::out_of_memory_error_java_heap());

   176   } else {

   177     // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support

   178     report_java_out_of_memory("GC overhead limit exceeded");

   179 

   180     if (JvmtiExport::should_post_resource_exhausted()) {

   181       JvmtiExport::post_resource_exhausted(

   182         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_JAVA_HEAP,

   183         "GC overhead limit exceeded");

   184     }

   185 

   186     THROW_OOP_0(Universe::out_of_memory_error_gc_overhead_limit());

   187   }

   188 }

   189 

   190 HeapWord* CollectedHeap::common_mem_allocate_init(Klass* klass, size_t size, TRAPS) {

   191   HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);

   192   init_obj(obj, size);

   193   return obj;

   194 }

   195 

   196 HeapWord* CollectedHeap::allocate_from_tlab(Klass* klass, Thread* thread, size_t size) {

   197   assert(UseTLAB, "should use UseTLAB");

   198 

   199   HeapWord* obj = thread->tlab().allocate(size);

   200   if (obj != NULL) {

   201     return obj;

   202   }

   203   // Otherwise...

   204   return allocate_from_tlab_slow(klass, thread, size);

   205 }

   206 

   207 void CollectedHeap::init_obj(HeapWord* obj, size_t size) {

   208   assert(obj != NULL, "cannot initialize NULL object");

   209   const size_t hs = oopDesc::header_size();

   210   assert(size >= hs, "unexpected object size");

   211   ((oop)obj)->set_klass_gap(0);

   212   Copy::fill_to_aligned_words(obj + hs, size - hs);

   213 }

   214 

   215 oop CollectedHeap::obj_allocate(Klass* klass, int size, TRAPS) {

   216   debug_only(check_for_valid_allocation_state());

   217   assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");

   218   assert(size >= 0, "int won't convert to size_t");

   219   HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);

   220   post_allocation_setup_obj(klass, obj, size);

   221   NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));

   222   return (oop)obj;

   223 }

   224 

   225 oop CollectedHeap::class_allocate(Klass* klass, int size, TRAPS) {

   226   debug_only(check_for_valid_allocation_state());

   227   assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");

   228   assert(size >= 0, "int won't convert to size_t");

   229   HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);

   230   post_allocation_setup_class(klass, obj, size); // set oop_size

   231   NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));

   232   return (oop)obj;

   233 }

   234 

   235 oop CollectedHeap::array_allocate(Klass* klass,

   236                                   int size,

   237                                   int length,

   238                                   TRAPS) {

   239   debug_only(check_for_valid_allocation_state());

   240   assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");

   241   assert(size >= 0, "int won't convert to size_t");

   242   HeapWord* obj = common_mem_allocate_init(klass, size, CHECK_NULL);

   243   post_allocation_setup_array(klass, obj, length);

   244   NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));

   245   return (oop)obj;

   246 }

   247 

   248 oop CollectedHeap::array_allocate_nozero(Klass* klass,

   249                                          int size,

   250                                          int length,

   251                                          TRAPS) {

   252   debug_only(check_for_valid_allocation_state());

   253   assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");

   254   assert(size >= 0, "int won't convert to size_t");

   255   HeapWord* obj = common_mem_allocate_noinit(klass, size, CHECK_NULL);

   256   ((oop)obj)->set_klass_gap(0);

   257   post_allocation_setup_array(klass, obj, length);

   258 #ifndef PRODUCT

   259   const size_t hs = oopDesc::header_size()+1;

   260   Universe::heap()->check_for_non_bad_heap_word_value(obj+hs, size-hs);

   261 #endif

   262   return (oop)obj;

   263 }

   264 

   265 inline HeapWord* CollectedHeap::align_allocation_or_fail(HeapWord* addr,

   266                                                          HeapWord* end,

   267                                                          unsigned short alignment_in_bytes) {

   268   if (alignment_in_bytes <= ObjectAlignmentInBytes) {

   269     return addr;

   270   }

   271 

   272   assert(is_aligned(addr, HeapWordSize),

   273          "Address " PTR_FORMAT " is not properly aligned.", p2i(addr));

   274   assert(is_aligned(alignment_in_bytes, HeapWordSize),

   275          "Alignment size %u is incorrect.", alignment_in_bytes);

   276 

   277   HeapWord* new_addr = align_up(addr, alignment_in_bytes);

   278   size_t padding = pointer_delta(new_addr, addr);

   279 

   280   if (padding == 0) {

   281     return addr;

   282   }

   283 

   284   if (padding < CollectedHeap::min_fill_size()) {

   285     padding += alignment_in_bytes / HeapWordSize;

   286     assert(padding >= CollectedHeap::min_fill_size(),

   287            "alignment_in_bytes %u is expect to be larger "

   288            "than the minimum object size", alignment_in_bytes);

   289     new_addr = addr + padding;

   290   }

   291 

   292   assert(new_addr > addr, "Unexpected arithmetic overflow "

   293          PTR_FORMAT " not greater than " PTR_FORMAT, p2i(new_addr), p2i(addr));

   294   if(new_addr < end) {

   295     CollectedHeap::fill_with_object(addr, padding);

   296     return new_addr;

   297   } else {

   298     return NULL;

   299   }

   300 }

   301 

   302 #ifndef PRODUCT

   303 

   304 inline bool

   305 CollectedHeap::promotion_should_fail(volatile size_t* count) {

   306   // Access to count is not atomic; the value does not have to be exact.

   307   if (PromotionFailureALot) {

   308     const size_t gc_num = total_collections();

   309     const size_t elapsed_gcs = gc_num - _promotion_failure_alot_gc_number;

   310     if (elapsed_gcs >= PromotionFailureALotInterval) {

   311       // Test for unsigned arithmetic wrap-around.

   312       if (++*count >= PromotionFailureALotCount) {

   313         *count = 0;

   314         return true;

   315       }

   316     }

   317   }

   318   return false;

   319 }

   320 

   321 inline bool CollectedHeap::promotion_should_fail() {

   322   return promotion_should_fail(&_promotion_failure_alot_count);

   323 }

   324 

   325 inline void CollectedHeap::reset_promotion_should_fail(volatile size_t* count) {

   326   if (PromotionFailureALot) {

   327     _promotion_failure_alot_gc_number = total_collections();

   328     *count = 0;

   329   }

   330 }

   331 

   332 inline void CollectedHeap::reset_promotion_should_fail() {

   333   reset_promotion_should_fail(&_promotion_failure_alot_count);

   334 }

   335 #endif  // #ifndef PRODUCT

   336 

   337 #endif // SHARE_VM_GC_SHARED_COLLECTEDHEAP_INLINE_HPP