59 base_offset += BytesPerInt;
60 }
61 assert(is_aligned(base_offset, HeapWordSize), "remaining array base must be 64 bit aligned");
62
63 const size_t header = heap_word_size(base_offset);
64 const size_t payload_size = _word_size - header;
65
66 if (payload_size <= segment_max) {
67 // To small to use segmented clearing
68 return ObjArrayAllocator::initialize(mem);
69 }
70
71 // Segmented clearing
72
73 // The array is going to be exposed before it has been completely
74 // cleared, therefore we can't expose the header at the end of this
75 // function. Instead explicitly initialize it according to our needs.
76
77 // Signal to the ZIterator that this is an invisible root, by setting
78 // the mark word to "marked". Reset to prototype() after the clearing.
79 arrayOopDesc::set_mark(mem, markWord::prototype().set_marked());
80 arrayOopDesc::release_set_klass(mem, _klass);
81 assert(_length >= 0, "length should be non-negative");
82 arrayOopDesc::set_length(mem, _length);
83
84 // Keep the array alive across safepoints through an invisible
85 // root. Invisible roots are not visited by the heap iterator
86 // and the marking logic will not attempt to follow its elements.
87 // Relocation and remembered set code know how to dodge iterating
88 // over such objects.
89 ZThreadLocalData::set_invisible_root(_thread, (zaddress_unsafe*)&mem);
90
91 uint32_t old_seqnum_before = ZGeneration::old()->seqnum();
92 uint32_t young_seqnum_before = ZGeneration::young()->seqnum();
93 uintptr_t color_before = ZPointerStoreGoodMask;
94 auto gc_safepoint_happened = [&]() {
95 return old_seqnum_before != ZGeneration::old()->seqnum() ||
96 young_seqnum_before != ZGeneration::young()->seqnum() ||
97 color_before != ZPointerStoreGoodMask;
98 };
99
100 bool seen_gc_safepoint = false;
130 // The first time we observe a GC safepoint in the yield point,
131 // we have to restart processing with 11 remembered bits.
132 seen_gc_safepoint = true;
133 return false;
134 }
135 }
136 return true;
137 };
138
139 if (!initialize_memory()) {
140 // Re-color with 11 remset bits if we got intercepted by a GC safepoint
141 const bool result = initialize_memory();
142 assert(result, "Array initialization should always succeed the second time");
143 }
144
145 mem_zap_end_padding(mem);
146
147 ZThreadLocalData::clear_invisible_root(_thread);
148
149 // Signal to the ZIterator that this is no longer an invisible root
150 oopDesc::release_set_mark(mem, markWord::prototype());
151
152 return cast_to_oop(mem);
153 }
|
59 base_offset += BytesPerInt;
60 }
61 assert(is_aligned(base_offset, HeapWordSize), "remaining array base must be 64 bit aligned");
62
63 const size_t header = heap_word_size(base_offset);
64 const size_t payload_size = _word_size - header;
65
66 if (payload_size <= segment_max) {
67 // To small to use segmented clearing
68 return ObjArrayAllocator::initialize(mem);
69 }
70
71 // Segmented clearing
72
73 // The array is going to be exposed before it has been completely
74 // cleared, therefore we can't expose the header at the end of this
75 // function. Instead explicitly initialize it according to our needs.
76
77 // Signal to the ZIterator that this is an invisible root, by setting
78 // the mark word to "marked". Reset to prototype() after the clearing.
79 if (UseCompactObjectHeaders) {
80 oopDesc::release_set_mark(mem, _klass->prototype_header().set_marked());
81 } else {
82 arrayOopDesc::set_mark(mem, markWord::prototype().set_marked());
83 arrayOopDesc::release_set_klass(mem, _klass);
84 }
85 assert(_length >= 0, "length should be non-negative");
86 arrayOopDesc::set_length(mem, _length);
87
88 // Keep the array alive across safepoints through an invisible
89 // root. Invisible roots are not visited by the heap iterator
90 // and the marking logic will not attempt to follow its elements.
91 // Relocation and remembered set code know how to dodge iterating
92 // over such objects.
93 ZThreadLocalData::set_invisible_root(_thread, (zaddress_unsafe*)&mem);
94
95 uint32_t old_seqnum_before = ZGeneration::old()->seqnum();
96 uint32_t young_seqnum_before = ZGeneration::young()->seqnum();
97 uintptr_t color_before = ZPointerStoreGoodMask;
98 auto gc_safepoint_happened = [&]() {
99 return old_seqnum_before != ZGeneration::old()->seqnum() ||
100 young_seqnum_before != ZGeneration::young()->seqnum() ||
101 color_before != ZPointerStoreGoodMask;
102 };
103
104 bool seen_gc_safepoint = false;
134 // The first time we observe a GC safepoint in the yield point,
135 // we have to restart processing with 11 remembered bits.
136 seen_gc_safepoint = true;
137 return false;
138 }
139 }
140 return true;
141 };
142
143 if (!initialize_memory()) {
144 // Re-color with 11 remset bits if we got intercepted by a GC safepoint
145 const bool result = initialize_memory();
146 assert(result, "Array initialization should always succeed the second time");
147 }
148
149 mem_zap_end_padding(mem);
150
151 ZThreadLocalData::clear_invisible_root(_thread);
152
153 // Signal to the ZIterator that this is no longer an invisible root
154 if (UseCompactObjectHeaders) {
155 oopDesc::release_set_mark(mem, _klass->prototype_header());
156 } else {
157 oopDesc::release_set_mark(mem, markWord::prototype());
158 }
159
160 return cast_to_oop(mem);
161 }
|