25
26 #include "precompiled.hpp"
27 #include "classfile/classLoaderData.inline.hpp"
28 #include "classfile/classLoaderDataGraph.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/vmClasses.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "gc/shared/gcLocker.hpp"
34 #include "gc/shared/gcVMOperations.hpp"
35 #include "gc/shared/workerThread.hpp"
36 #include "jfr/jfrEvents.hpp"
37 #include "jvm.h"
38 #include "memory/allocation.inline.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "memory/universe.hpp"
41 #include "oops/fieldStreams.inline.hpp"
42 #include "oops/klass.inline.hpp"
43 #include "oops/objArrayKlass.hpp"
44 #include "oops/objArrayOop.inline.hpp"
45 #include "oops/oop.inline.hpp"
46 #include "oops/typeArrayOop.inline.hpp"
47 #include "runtime/continuationWrapper.inline.hpp"
48 #include "runtime/frame.inline.hpp"
49 #include "runtime/handles.inline.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/javaThread.inline.hpp"
52 #include "runtime/jniHandles.hpp"
53 #include "runtime/os.hpp"
54 #include "runtime/threads.hpp"
55 #include "runtime/threadSMR.hpp"
56 #include "runtime/vframe.hpp"
57 #include "runtime/vmOperations.hpp"
58 #include "runtime/vmThread.hpp"
59 #include "runtime/timerTrace.hpp"
60 #include "services/heapDumper.hpp"
61 #include "services/heapDumperCompression.hpp"
62 #include "services/threadService.hpp"
63 #include "utilities/checkedCast.hpp"
64 #include "utilities/macros.hpp"
65 #include "utilities/ostream.hpp"
66 #ifdef LINUX
67 #include "os_linux.hpp"
299 * 7: double array
300 * 8: byte array
301 * 9: short array
302 * 10: int array
303 * 11: long array
304 * [u1]* elements
305 *
306 * HPROF_CPU_SAMPLES a set of sample traces of running threads
307 *
308 * u4 total number of samples
309 * u4 # of traces
310 * [u4 # of samples
311 * u4]* stack trace serial number
312 *
313 * HPROF_CONTROL_SETTINGS the settings of on/off switches
314 *
315 * u4 0x00000001: alloc traces on/off
316 * 0x00000002: cpu sampling on/off
317 * u2 stack trace depth
318 *
319 *
320 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
321 * be generated as a sequence of heap dump segments. This sequence is
322 * terminated by an end record. The additional tags allowed by format
323 * "JAVA PROFILE 1.0.2" are:
324 *
325 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
326 *
327 * [heap dump sub-records]*
328 * The same sub-record types allowed by HPROF_HEAP_DUMP
329 *
330 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
331 *
332 */
333
334
335 // HPROF tags
336
337 enum hprofTag : u1 {
338 // top-level records
339 HPROF_UTF8 = 0x01,
340 HPROF_LOAD_CLASS = 0x02,
341 HPROF_UNLOAD_CLASS = 0x03,
342 HPROF_FRAME = 0x04,
343 HPROF_TRACE = 0x05,
344 HPROF_ALLOC_SITES = 0x06,
345 HPROF_HEAP_SUMMARY = 0x07,
346 HPROF_START_THREAD = 0x0A,
347 HPROF_END_THREAD = 0x0B,
348 HPROF_HEAP_DUMP = 0x0C,
349 HPROF_CPU_SAMPLES = 0x0D,
350 HPROF_CONTROL_SETTINGS = 0x0E,
351
352 // 1.0.2 record types
353 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
354 HPROF_HEAP_DUMP_END = 0x2C,
355
356 // field types
357 HPROF_ARRAY_OBJECT = 0x01,
358 HPROF_NORMAL_OBJECT = 0x02,
359 HPROF_BOOLEAN = 0x04,
360 HPROF_CHAR = 0x05,
361 HPROF_FLOAT = 0x06,
362 HPROF_DOUBLE = 0x07,
363 HPROF_BYTE = 0x08,
364 HPROF_SHORT = 0x09,
365 HPROF_INT = 0x0A,
366 HPROF_LONG = 0x0B,
367
368 // data-dump sub-records
369 HPROF_GC_ROOT_UNKNOWN = 0xFF,
370 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
371 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
372 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
373 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
374 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
375 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
376 HPROF_GC_ROOT_MONITOR_USED = 0x07,
377 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
378 HPROF_GC_CLASS_DUMP = 0x20,
379 HPROF_GC_INSTANCE_DUMP = 0x21,
380 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
381 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
382 };
383
384 // Default stack trace ID (used for dummy HPROF_TRACE record)
385 enum {
386 STACK_TRACE_ID = 1,
387 INITIAL_CLASS_COUNT = 200
388 };
389
390 // Supports I/O operations for a dump
391 // Base class for dump and parallel dump
392 class AbstractDumpWriter : public CHeapObj<mtInternal> {
393 protected:
394 enum {
395 io_buffer_max_size = 1*M,
396 dump_segment_header_size = 9
397 };
398
399 char* _buffer; // internal buffer
400 size_t _size;
401 size_t _pos;
402
403 bool _in_dump_segment; // Are we currently in a dump segment?
404 bool _is_huge_sub_record; // Are we writing a sub-record larger than the buffer size?
405 DEBUG_ONLY(size_t _sub_record_left;) // The bytes not written for the current sub-record.
406 DEBUG_ONLY(bool _sub_record_ended;) // True if we have called the end_sub_record().
407
408 char* buffer() const { return _buffer; }
409 size_t buffer_size() const { return _size; }
722 }
723 }
724
725 class DumperClassCacheTable;
726 class DumperClassCacheTableEntry;
727
728 // Support class with a collection of functions used when dumping the heap
729 class DumperSupport : AllStatic {
730 public:
731
732 // write a header of the given type
733 static void write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len);
734
735 // returns hprof tag for the given type signature
736 static hprofTag sig2tag(Symbol* sig);
737 // returns hprof tag for the given basic type
738 static hprofTag type2tag(BasicType type);
739 // Returns the size of the data to write.
740 static u4 sig2size(Symbol* sig);
741
742 // returns the size of the instance of the given class
743 static u4 instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry = nullptr);
744
745 // dump a jfloat
746 static void dump_float(AbstractDumpWriter* writer, jfloat f);
747 // dump a jdouble
748 static void dump_double(AbstractDumpWriter* writer, jdouble d);
749 // dumps the raw value of the given field
750 static void dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset);
751 // returns the size of the static fields; also counts the static fields
752 static u4 get_static_fields_size(InstanceKlass* ik, u2& field_count);
753 // dumps static fields of the given class
754 static void dump_static_fields(AbstractDumpWriter* writer, Klass* k);
755 // dump the raw values of the instance fields of the given object
756 static void dump_instance_fields(AbstractDumpWriter* writer, oop o, DumperClassCacheTableEntry* class_cache_entry);
757 // get the count of the instance fields for a given class
758 static u2 get_instance_fields_count(InstanceKlass* ik);
759 // dumps the definition of the instance fields for a given class
760 static void dump_instance_field_descriptors(AbstractDumpWriter* writer, Klass* k);
761 // creates HPROF_GC_INSTANCE_DUMP record for the given object
762 static void dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache);
763 // creates HPROF_GC_CLASS_DUMP record for the given instance class
764 static void dump_instance_class(AbstractDumpWriter* writer, Klass* k);
765 // creates HPROF_GC_CLASS_DUMP record for a given array class
766 static void dump_array_class(AbstractDumpWriter* writer, Klass* k);
767
768 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
769 static void dump_object_array(AbstractDumpWriter* writer, objArrayOop array);
770 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
771 static void dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array);
772 // create HPROF_FRAME record for the given method and bci
773 static void dump_stack_frame(AbstractDumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
774
775 // check if we need to truncate an array
776 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size);
777
778 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
779 static void end_of_dump(AbstractDumpWriter* writer);
780
781 static oop mask_dormant_archived_object(oop o, oop ref_obj) {
782 if (o != nullptr && o->klass()->java_mirror_no_keepalive() == nullptr) {
783 // Ignore this object since the corresponding java mirror is not loaded.
784 // Might be a dormant archive object.
785 report_dormant_archived_object(o, ref_obj);
786 return nullptr;
787 } else {
788 return o;
789 }
790 }
791
792 static void report_dormant_archived_object(oop o, oop ref_obj) {
793 if (log_is_enabled(Trace, cds, heap)) {
794 ResourceMark rm;
795 if (ref_obj != nullptr) {
796 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)",
797 p2i(o), o->klass()->external_name(),
798 p2i(ref_obj), ref_obj->klass()->external_name());
799 } else {
800 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s)",
801 p2i(o), o->klass()->external_name());
802 }
803 }
804 }
805 };
806
807 // Hash table of klasses to the klass metadata. This should greatly improve the
808 // hash dumping performance. This hash table is supposed to be used by a single
809 // thread only.
810 //
811 class DumperClassCacheTableEntry : public CHeapObj<mtServiceability> {
812 friend class DumperClassCacheTable;
813 private:
814 GrowableArray<char> _sigs_start;
815 GrowableArray<int> _offsets;
816 u4 _instance_size;
817 int _entries;
818
819 public:
820 DumperClassCacheTableEntry() : _instance_size(0), _entries(0) {};
821
822 int field_count() { return _entries; }
823 char sig_start(int field_idx) { return _sigs_start.at(field_idx); }
824 int offset(int field_idx) { return _offsets.at(field_idx); }
825 u4 instance_size() { return _instance_size; }
826 };
827
828 class DumperClassCacheTable {
829 private:
830 // ResourceHashtable SIZE is specified at compile time so we
831 // use 1031 which is the first prime after 1024.
832 static constexpr size_t TABLE_SIZE = 1031;
833
834 // Maintain the cache for N classes. This limits memory footprint
835 // impact, regardless of how many classes we have in the dump.
836 // This also improves look up performance by keeping the statically
837 // sized table from overloading.
838 static constexpr int CACHE_TOP = 256;
839
840 typedef ResourceHashtable<InstanceKlass*, DumperClassCacheTableEntry*,
841 TABLE_SIZE, AnyObj::C_HEAP, mtServiceability> PtrTable;
842 PtrTable* _ptrs;
843
852 bool do_entry(InstanceKlass*& key, DumperClassCacheTableEntry*& entry) {
853 delete entry;
854 return true;
855 }
856 } cleanup;
857 table->unlink(&cleanup);
858 }
859
860 public:
861 DumperClassCacheTableEntry* lookup_or_create(InstanceKlass* ik) {
862 if (_last_ik == ik) {
863 return _last_entry;
864 }
865
866 DumperClassCacheTableEntry* entry;
867 DumperClassCacheTableEntry** from_cache = _ptrs->get(ik);
868 if (from_cache == nullptr) {
869 entry = new DumperClassCacheTableEntry();
870 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
871 if (!fld.access_flags().is_static()) {
872 Symbol* sig = fld.signature();
873 entry->_sigs_start.push(sig->char_at(0));
874 entry->_offsets.push(fld.offset());
875 entry->_entries++;
876 entry->_instance_size += DumperSupport::sig2size(sig);
877 }
878 }
879
880 if (_ptrs->number_of_entries() >= CACHE_TOP) {
881 // We do not track the individual hit rates for table entries.
882 // Purge the entire table, and let the cache catch up with new
883 // distribution.
884 unlink_all(_ptrs);
885 }
886
887 _ptrs->put(ik, entry);
888 } else {
889 entry = *from_cache;
890 }
891
892 // Remember for single-slot cache.
893 _last_ik = ik;
894 _last_entry = entry;
895
896 return entry;
966 }
967
968 // dump a jfloat
969 void DumperSupport::dump_float(AbstractDumpWriter* writer, jfloat f) {
970 if (g_isnan(f)) {
971 writer->write_u4(0x7fc00000); // collapsing NaNs
972 } else {
973 writer->write_u4(bit_cast<u4>(f));
974 }
975 }
976
977 // dump a jdouble
978 void DumperSupport::dump_double(AbstractDumpWriter* writer, jdouble d) {
979 if (g_isnan(d)) {
980 writer->write_u8(0x7ff80000ull << 32); // collapsing NaNs
981 } else {
982 writer->write_u8(bit_cast<u8>(d));
983 }
984 }
985
986 // dumps the raw value of the given field
987 void DumperSupport::dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset) {
988 switch (type) {
989 case JVM_SIGNATURE_CLASS :
990 case JVM_SIGNATURE_ARRAY : {
991 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF | AS_NO_KEEPALIVE>(offset);
992 o = mask_dormant_archived_object(o, obj);
993 assert(oopDesc::is_oop_or_null(o), "Expected an oop or nullptr at " PTR_FORMAT, p2i(o));
994 writer->write_objectID(o);
995 break;
996 }
997 case JVM_SIGNATURE_BYTE : {
998 jbyte b = obj->byte_field(offset);
999 writer->write_u1(b);
1000 break;
1001 }
1002 case JVM_SIGNATURE_CHAR : {
1003 jchar c = obj->char_field(offset);
1004 writer->write_u2(c);
1005 break;
1024 writer->write_u4(i);
1025 break;
1026 }
1027 case JVM_SIGNATURE_LONG : {
1028 jlong l = obj->long_field(offset);
1029 writer->write_u8(l);
1030 break;
1031 }
1032 case JVM_SIGNATURE_BOOLEAN : {
1033 jboolean b = obj->bool_field(offset);
1034 writer->write_u1(b);
1035 break;
1036 }
1037 default : {
1038 ShouldNotReachHere();
1039 break;
1040 }
1041 }
1042 }
1043
1044 // returns the size of the instance of the given class
1045 u4 DumperSupport::instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry) {
1046 if (class_cache_entry != nullptr) {
1047 return class_cache_entry->instance_size();
1048 } else {
1049 u4 size = 0;
1050 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
1051 if (!fld.access_flags().is_static()) {
1052 size += sig2size(fld.signature());
1053 }
1054 }
1055 return size;
1056 }
1057 }
1058
1059 u4 DumperSupport::get_static_fields_size(InstanceKlass* ik, u2& field_count) {
1060 field_count = 0;
1061 u4 size = 0;
1062
1063 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
1064 if (fldc.access_flags().is_static()) {
1065 field_count++;
1066 size += sig2size(fldc.signature());
1067 }
1068 }
1069
1070 // Add in resolved_references which is referenced by the cpCache
1071 // The resolved_references is an array per InstanceKlass holding the
1072 // strings and other oops resolved from the constant pool.
1073 oop resolved_references = ik->constants()->resolved_references_or_null();
1074 if (resolved_references != nullptr) {
1075 field_count++;
1076 size += sizeof(address);
1077
1078 // Add in the resolved_references of the used previous versions of the class
1079 // in the case of RedefineClasses
1080 InstanceKlass* prev = ik->previous_versions();
1081 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1082 field_count++;
1083 size += sizeof(address);
1084 prev = prev->previous_versions();
1085 }
1086 }
1087
1088 // We write the value itself plus a name and a one byte type tag per field.
1089 return checked_cast<u4>(size + field_count * (sizeof(address) + 1));
1090 }
1091
1092 // dumps static fields of the given class
1093 void DumperSupport::dump_static_fields(AbstractDumpWriter* writer, Klass* k) {
1094 InstanceKlass* ik = InstanceKlass::cast(k);
1095
1096 // dump the field descriptors and raw values
1097 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
1098 if (fld.access_flags().is_static()) {
1099 Symbol* sig = fld.signature();
1100
1101 writer->write_symbolID(fld.name()); // name
1102 writer->write_u1(sig2tag(sig)); // type
1103
1104 // value
1105 dump_field_value(writer, sig->char_at(0), ik->java_mirror(), fld.offset());
1106 }
1107 }
1108
1109 // Add resolved_references for each class that has them
1110 oop resolved_references = ik->constants()->resolved_references_or_null();
1111 if (resolved_references != nullptr) {
1112 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1113 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1114 writer->write_objectID(resolved_references);
1115
1116 // Also write any previous versions
1117 InstanceKlass* prev = ik->previous_versions();
1118 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1119 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1120 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1121 writer->write_objectID(prev->constants()->resolved_references());
1122 prev = prev->previous_versions();
1123 }
1124 }
1125 }
1126
1127 // dump the raw values of the instance fields of the given object
1128 void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, DumperClassCacheTableEntry* class_cache_entry) {
1129 assert(class_cache_entry != nullptr, "Pre-condition: must be provided");
1130 for (int idx = 0; idx < class_cache_entry->field_count(); idx++) {
1131 dump_field_value(writer, class_cache_entry->sig_start(idx), o, class_cache_entry->offset(idx));
1132 }
1133 }
1134
1135 // dumps the definition of the instance fields for a given class
1136 u2 DumperSupport::get_instance_fields_count(InstanceKlass* ik) {
1137 u2 field_count = 0;
1138
1139 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
1140 if (!fldc.access_flags().is_static()) field_count++;
1141 }
1142
1143 return field_count;
1144 }
1145
1146 // dumps the definition of the instance fields for a given class
1147 void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, Klass* k) {
1148 InstanceKlass* ik = InstanceKlass::cast(k);
1149
1150 // dump the field descriptors
1151 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
1152 if (!fld.access_flags().is_static()) {
1153 Symbol* sig = fld.signature();
1154
1155 writer->write_symbolID(fld.name()); // name
1156 writer->write_u1(sig2tag(sig)); // type
1157 }
1158 }
1159 }
1160
1161 // creates HPROF_GC_INSTANCE_DUMP record for the given object
1162 void DumperSupport::dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache) {
1163 InstanceKlass* ik = InstanceKlass::cast(o->klass());
1164
1165 DumperClassCacheTableEntry* cache_entry = class_cache->lookup_or_create(ik);
1166
1167 u4 is = instance_size(ik, cache_entry);
1168 u4 size = 1 + sizeof(address) + 4 + sizeof(address) + 4 + is;
1169
1170 writer->start_sub_record(HPROF_GC_INSTANCE_DUMP, size);
1171 writer->write_objectID(o);
1172 writer->write_u4(STACK_TRACE_ID);
1173
1174 // class ID
1175 writer->write_classID(ik);
1176
1177 // number of bytes that follow
1178 writer->write_u4(is);
1179
1180 // field values
1181 dump_instance_fields(writer, o, cache_entry);
1182
1183 writer->end_sub_record();
1184 }
1185
1186 // creates HPROF_GC_CLASS_DUMP record for the given instance class
1187 void DumperSupport::dump_instance_class(AbstractDumpWriter* writer, Klass* k) {
1188 InstanceKlass* ik = InstanceKlass::cast(k);
1189
1190 // We can safepoint and do a heap dump at a point where we have a Klass,
1191 // but no java mirror class has been setup for it. So we need to check
1192 // that the class is at least loaded, to avoid crash from a null mirror.
1193 if (!ik->is_loaded()) {
1194 return;
1195 }
1196
1197 u2 static_fields_count = 0;
1198 u4 static_size = get_static_fields_size(ik, static_fields_count);
1199 u2 instance_fields_count = get_instance_fields_count(ik);
1200 u4 instance_fields_size = instance_fields_count * (sizeof(address) + 1);
1201 u4 size = checked_cast<u4>(1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + static_size + 2 + instance_fields_size);
1206 writer->write_classID(ik);
1207 writer->write_u4(STACK_TRACE_ID);
1208
1209 // super class ID
1210 InstanceKlass* java_super = ik->java_super();
1211 if (java_super == nullptr) {
1212 writer->write_objectID(oop(nullptr));
1213 } else {
1214 writer->write_classID(java_super);
1215 }
1216
1217 writer->write_objectID(ik->class_loader());
1218 writer->write_objectID(ik->signers());
1219 writer->write_objectID(ik->protection_domain());
1220
1221 // reserved
1222 writer->write_objectID(oop(nullptr));
1223 writer->write_objectID(oop(nullptr));
1224
1225 // instance size
1226 writer->write_u4(DumperSupport::instance_size(ik));
1227
1228 // size of constant pool - ignored by HAT 1.1
1229 writer->write_u2(0);
1230
1231 // static fields
1232 writer->write_u2(static_fields_count);
1233 dump_static_fields(writer, ik);
1234
1235 // description of instance fields
1236 writer->write_u2(instance_fields_count);
1237 dump_instance_field_descriptors(writer, ik);
1238
1239 writer->end_sub_record();
1240 }
1241
1242 // creates HPROF_GC_CLASS_DUMP record for the given array class
1243 void DumperSupport::dump_array_class(AbstractDumpWriter* writer, Klass* k) {
1244 InstanceKlass* ik = nullptr; // bottom class for object arrays, null for primitive type arrays
1245 if (k->is_objArray_klass()) {
1246 Klass *bk = ObjArrayKlass::cast(k)->bottom_klass();
1260 assert(java_super != nullptr, "checking");
1261 writer->write_classID(java_super);
1262
1263 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->class_loader());
1264 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->signers());
1265 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->protection_domain());
1266
1267 writer->write_objectID(oop(nullptr)); // reserved
1268 writer->write_objectID(oop(nullptr));
1269 writer->write_u4(0); // instance size
1270 writer->write_u2(0); // constant pool
1271 writer->write_u2(0); // static fields
1272 writer->write_u2(0); // instance fields
1273
1274 writer->end_sub_record();
1275
1276 }
1277
1278 // Hprof uses an u4 as record length field,
1279 // which means we need to truncate arrays that are too long.
1280 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) {
1281 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1282 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
1283
1284 int length = array->length();
1285
1286 int type_size;
1287 if (type == T_OBJECT) {
1288 type_size = sizeof(address);
1289 } else {
1290 type_size = type2aelembytes(type);
1291 }
1292
1293 size_t length_in_bytes = (size_t)length * type_size;
1294 uint max_bytes = max_juint - header_size;
1295
1296 if (length_in_bytes > max_bytes) {
1297 length = max_bytes / type_size;
1298 length_in_bytes = (size_t)length * type_size;
1299
1300 warning("cannot dump array of type %s[] with length %d; truncating to length %d",
1301 type2name_tab[type], array->length(), length);
1302 }
1303 return length;
1304 }
1305
1306 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1307 void DumperSupport::dump_object_array(AbstractDumpWriter* writer, objArrayOop array) {
1308 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
1309 short header_size = 1 + 2 * 4 + 2 * sizeof(address);
1310 int length = calculate_array_max_length(writer, array, header_size);
1311 u4 size = checked_cast<u4>(header_size + length * sizeof(address));
1312
1313 writer->start_sub_record(HPROF_GC_OBJ_ARRAY_DUMP, size);
1314 writer->write_objectID(array);
1315 writer->write_u4(STACK_TRACE_ID);
1316 writer->write_u4(length);
1317
1318 // array class ID
1319 writer->write_classID(array->klass());
1320
1321 // [id]* elements
1322 for (int index = 0; index < length; index++) {
1323 oop o = array->obj_at(index);
1324 o = mask_dormant_archived_object(o, array);
1325 writer->write_objectID(o);
1326 }
1327
1328 writer->end_sub_record();
1329 }
1330
1331 #define WRITE_ARRAY(Array, Type, Size, Length) \
1332 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
1333
1334 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1335 void DumperSupport::dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array) {
1336 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1337 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID)
1338 short header_size = 2 * 1 + 2 * 4 + sizeof(address);
1339
1340 int length = calculate_array_max_length(writer, array, header_size);
1341 int type_size = type2aelembytes(type);
1342 u4 length_in_bytes = (u4)length * type_size;
1343 u4 size = header_size + length_in_bytes;
1344
1345 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
1346 writer->write_objectID(array);
1347 writer->write_u4(STACK_TRACE_ID);
1348 writer->write_u4(length);
1349 writer->write_u1(type2tag(type));
1350
1432 int bci) {
1433 int line_number;
1434 if (m->is_native()) {
1435 line_number = -3; // native frame
1436 } else {
1437 line_number = m->line_number_from_bci(bci);
1438 }
1439
1440 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1441 writer->write_id(frame_serial_num); // frame serial number
1442 writer->write_symbolID(m->name()); // method's name
1443 writer->write_symbolID(m->signature()); // method's signature
1444
1445 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass");
1446 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1447 writer->write_u4(class_serial_num); // class serial number
1448 writer->write_u4((u4) line_number); // line number
1449 }
1450
1451
1452 // Support class used to generate HPROF_UTF8 records from the entries in the
1453 // SymbolTable.
1454
1455 class SymbolTableDumper : public SymbolClosure {
1456 private:
1457 AbstractDumpWriter* _writer;
1458 AbstractDumpWriter* writer() const { return _writer; }
1459 public:
1460 SymbolTableDumper(AbstractDumpWriter* writer) { _writer = writer; }
1461 void do_symbol(Symbol** p);
1462 };
1463
1464 void SymbolTableDumper::do_symbol(Symbol** p) {
1465 ResourceMark rm;
1466 Symbol* sym = *p;
1467 int len = sym->utf8_length();
1468 if (len > 0) {
1469 char* s = sym->as_utf8();
1470 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1471 writer()->write_symbolID(sym);
1923 return;
1924 }
1925 }
1926
1927 if (DumperSupport::mask_dormant_archived_object(o, nullptr) == nullptr) {
1928 return;
1929 }
1930
1931 if (o->is_instance()) {
1932 // create a HPROF_GC_INSTANCE record for each object
1933 DumperSupport::dump_instance(writer(), o, &_class_cache);
1934 // If we encounter an unmounted virtual thread it needs to be dumped explicitly
1935 // (mounted virtual threads are dumped with their carriers).
1936 if (java_lang_VirtualThread::is_instance(o)
1937 && ThreadDumper::should_dump_vthread(o) && !ThreadDumper::is_vthread_mounted(o)) {
1938 _vthread_dumper->dump_vthread(o, writer());
1939 }
1940 } else if (o->is_objArray()) {
1941 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
1942 DumperSupport::dump_object_array(writer(), objArrayOop(o));
1943 } else if (o->is_typeArray()) {
1944 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
1945 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
1946 }
1947 }
1948
1949 // The dumper controller for parallel heap dump
1950 class DumperController : public CHeapObj<mtInternal> {
1951 private:
1952 Monitor* _lock;
1953 Mutex* _global_writer_lock;
1954
1955 const uint _dumper_number;
1956 uint _complete_number;
1957
1958 bool _started; // VM dumper started and acquired global writer lock
1959
1960 public:
1961 DumperController(uint number) :
1962 // _lock and _global_writer_lock are used for synchronization between GC worker threads inside safepoint,
2002 _complete_number++;
2003 // propagate local error to global if any
2004 if (local_writer->has_error()) {
2005 global_writer->set_error(local_writer->error());
2006 }
2007 ml.notify();
2008 }
2009
2010 void wait_all_dumpers_complete() {
2011 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2012 while (_complete_number != _dumper_number) {
2013 ml.wait();
2014 }
2015 }
2016 };
2017
2018 // DumpMerger merges separate dump files into a complete one
2019 class DumpMerger : public StackObj {
2020 private:
2021 DumpWriter* _writer;
2022 const char* _path;
2023 bool _has_error;
2024 int _dump_seq;
2025
2026 private:
2027 void merge_file(const char* path);
2028 void merge_done();
2029 void set_error(const char* msg);
2030
2031 public:
2032 DumpMerger(const char* path, DumpWriter* writer, int dump_seq) :
2033 _writer(writer),
2034 _path(path),
2035 _has_error(_writer->has_error()),
2036 _dump_seq(dump_seq) {}
2037
2038 void do_merge();
2039
2040 // returns path for the parallel DumpWriter (resource allocated)
2041 static char* get_writer_path(const char* base_path, int seq);
2042
2043 };
2044
2045 char* DumpMerger::get_writer_path(const char* base_path, int seq) {
2046 // approximate required buffer size
2047 size_t buf_size = strlen(base_path)
2048 + 2 // ".p"
2049 + 10 // number (that's enough for 2^32 parallel dumpers)
2050 + 1; // '\0'
2051
2052 char* path = NEW_RESOURCE_ARRAY(char, buf_size);
2053 memset(path, 0, buf_size);
2054
2055 os::snprintf(path, buf_size, "%s.p%d", base_path, seq);
2056
2057 return path;
2058 }
2059
2060
2061 void DumpMerger::merge_done() {
2062 // Writes the HPROF_HEAP_DUMP_END record.
2063 if (!_has_error) {
2064 DumperSupport::end_of_dump(_writer);
2065 _writer->flush();
2066 }
2067 _dump_seq = 0; //reset
2068 }
2069
2070 void DumpMerger::set_error(const char* msg) {
2071 assert(msg != nullptr, "sanity check");
2072 log_error(heapdump)("%s (file: %s)", msg, _path);
2073 _writer->set_error(msg);
2074 _has_error = true;
2075 }
2076
2077 #ifdef LINUX
2078 // Merge segmented heap files via sendfile, it's more efficient than the
2079 // read+write combination, which would require transferring data to and from
2080 // user space.
2081 void DumpMerger::merge_file(const char* path) {
2082 TraceTime timer("Merge segmented heap file directly", TRACETIME_LOG(Info, heapdump));
2083
2084 int segment_fd = os::open(path, O_RDONLY, 0);
2085 if (segment_fd == -1) {
2180 }
2181 };
2182
2183 // The VM operation that performs the heap dump
2184 class VM_HeapDumper : public VM_GC_Operation, public WorkerTask, public UnmountedVThreadDumper {
2185 private:
2186 static VM_HeapDumper* _global_dumper;
2187 static DumpWriter* _global_writer;
2188 DumpWriter* _local_writer;
2189 JavaThread* _oome_thread;
2190 Method* _oome_constructor;
2191 bool _gc_before_heap_dump;
2192 GrowableArray<Klass*>* _klass_map;
2193
2194 ThreadDumper** _thread_dumpers; // platform, carrier and mounted virtual threads
2195 int _thread_dumpers_count;
2196 volatile int _thread_serial_num;
2197 volatile int _frame_serial_num;
2198
2199 volatile int _dump_seq;
2200 // parallel heap dump support
2201 uint _num_dumper_threads;
2202 DumperController* _dumper_controller;
2203 ParallelObjectIterator* _poi;
2204
2205 // Dumper id of VMDumper thread.
2206 static const int VMDumperId = 0;
2207 // VM dumper dumps both heap and non-heap data, other dumpers dump heap-only data.
2208 static bool is_vm_dumper(int dumper_id) { return dumper_id == VMDumperId; }
2209 // the 1st dumper calling get_next_dumper_id becomes VM dumper
2210 int get_next_dumper_id() {
2211 return Atomic::fetch_then_add(&_dump_seq, 1);
2212 }
2213
2214 // accessors and setters
2215 static VM_HeapDumper* dumper() { assert(_global_dumper != nullptr, "Error"); return _global_dumper; }
2216 static DumpWriter* writer() { assert(_global_writer != nullptr, "Error"); return _global_writer; }
2217
2218 void set_global_dumper() {
2219 assert(_global_dumper == nullptr, "Error");
2280 }
2281
2282 ~VM_HeapDumper() {
2283 if (_thread_dumpers != nullptr) {
2284 for (int i = 0; i < _thread_dumpers_count; i++) {
2285 delete _thread_dumpers[i];
2286 }
2287 FREE_C_HEAP_ARRAY(ThreadDumper*, _thread_dumpers);
2288 }
2289
2290 if (_dumper_controller != nullptr) {
2291 delete _dumper_controller;
2292 _dumper_controller = nullptr;
2293 }
2294 delete _klass_map;
2295 }
2296 int dump_seq() { return _dump_seq; }
2297 bool is_parallel_dump() { return _num_dumper_threads > 1; }
2298 void prepare_parallel_dump(WorkerThreads* workers);
2299
2300 VMOp_Type type() const { return VMOp_HeapDumper; }
2301 virtual bool doit_prologue();
2302 void doit();
2303 void work(uint worker_id);
2304
2305 // UnmountedVThreadDumper implementation
2306 void dump_vthread(oop vt, AbstractDumpWriter* segment_writer);
2307 };
2308
2309 VM_HeapDumper* VM_HeapDumper::_global_dumper = nullptr;
2310 DumpWriter* VM_HeapDumper::_global_writer = nullptr;
2311
2312 bool VM_HeapDumper::skip_operation() const {
2313 return false;
2314 }
2315
2316 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
2317 void DumperSupport::end_of_dump(AbstractDumpWriter* writer) {
2318 writer->finish_dump_segment();
2319
2454 _dumper_controller->lock_global_writer();
2455 _dumper_controller->signal_start();
2456 } else {
2457 _dumper_controller->wait_for_start_signal();
2458 }
2459
2460 if (is_vm_dumper(dumper_id)) {
2461 TraceTime timer("Dump non-objects", TRACETIME_LOG(Info, heapdump));
2462 // Write the file header - we always use 1.0.2
2463 const char* header = "JAVA PROFILE 1.0.2";
2464
2465 // header is few bytes long - no chance to overflow int
2466 writer()->write_raw(header, strlen(header) + 1); // NUL terminated
2467 writer()->write_u4(oopSize);
2468 // timestamp is current time in ms
2469 writer()->write_u8(os::javaTimeMillis());
2470 // HPROF_UTF8 records
2471 SymbolTableDumper sym_dumper(writer());
2472 SymbolTable::symbols_do(&sym_dumper);
2473
2474 // write HPROF_LOAD_CLASS records
2475 {
2476 LockedClassesDo locked_load_classes(&do_load_class);
2477 ClassLoaderDataGraph::classes_do(&locked_load_classes);
2478 }
2479
2480 // write HPROF_FRAME and HPROF_TRACE records
2481 // this must be called after _klass_map is built when iterating the classes above.
2482 dump_stack_traces(writer());
2483
2484 // unlock global writer, so parallel dumpers can dump stack traces of unmounted virtual threads
2485 _dumper_controller->unlock_global_writer();
2486 }
2487
2488 // HPROF_HEAP_DUMP/HPROF_HEAP_DUMP_SEGMENT starts here
2489
2490 ResourceMark rm;
2491 // share global compressor, local DumpWriter is not responsible for its life cycle
2492 DumpWriter segment_writer(DumpMerger::get_writer_path(writer()->get_file_path(), dumper_id),
2493 writer()->is_overwrite(), writer()->compressor());
2641 (error() != nullptr) ? error() : "reason unknown");
2642 }
2643 return -1;
2644 }
2645
2646 // generate the segmented heap dump into separate files
2647 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome, num_dump_threads);
2648 VMThread::execute(&dumper);
2649
2650 // record any error that the writer may have encountered
2651 set_error(writer.error());
2652
2653 // Heap dump process is done in two phases
2654 //
2655 // Phase 1: Concurrent threads directly write heap data to multiple heap files.
2656 // This is done by VM_HeapDumper, which is performed within safepoint.
2657 //
2658 // Phase 2: Merge multiple heap files into one complete heap dump file.
2659 // This is done by DumpMerger, which is performed outside safepoint
2660
2661 DumpMerger merger(path, &writer, dumper.dump_seq());
2662 Thread* current_thread = Thread::current();
2663 if (current_thread->is_AttachListener_thread()) {
2664 // perform heapdump file merge operation in the current thread prevents us
2665 // from occupying the VM Thread, which in turn affects the occurrence of
2666 // GC and other VM operations.
2667 merger.do_merge();
2668 } else {
2669 // otherwise, performs it by VM thread
2670 VM_HeapDumpMerge op(&merger);
2671 VMThread::execute(&op);
2672 }
2673 if (writer.error() != nullptr) {
2674 set_error(writer.error());
2675 }
2676
2677 // emit JFR event
2678 if (error() == nullptr) {
2679 event.set_destination(path);
2680 event.set_gcBeforeDump(_gc_before_heap_dump);
2681 event.set_size(writer.bytes_written());
|
25
26 #include "precompiled.hpp"
27 #include "classfile/classLoaderData.inline.hpp"
28 #include "classfile/classLoaderDataGraph.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/vmClasses.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "gc/shared/gcLocker.hpp"
34 #include "gc/shared/gcVMOperations.hpp"
35 #include "gc/shared/workerThread.hpp"
36 #include "jfr/jfrEvents.hpp"
37 #include "jvm.h"
38 #include "memory/allocation.inline.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "memory/universe.hpp"
41 #include "oops/fieldStreams.inline.hpp"
42 #include "oops/klass.inline.hpp"
43 #include "oops/objArrayKlass.hpp"
44 #include "oops/objArrayOop.inline.hpp"
45 #include "oops/flatArrayKlass.hpp"
46 #include "oops/flatArrayOop.inline.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/typeArrayOop.inline.hpp"
49 #include "runtime/continuationWrapper.inline.hpp"
50 #include "runtime/fieldDescriptor.inline.hpp"
51 #include "runtime/frame.inline.hpp"
52 #include "runtime/handles.inline.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/javaThread.inline.hpp"
55 #include "runtime/jniHandles.hpp"
56 #include "runtime/os.hpp"
57 #include "runtime/threads.hpp"
58 #include "runtime/threadSMR.hpp"
59 #include "runtime/vframe.hpp"
60 #include "runtime/vmOperations.hpp"
61 #include "runtime/vmThread.hpp"
62 #include "runtime/timerTrace.hpp"
63 #include "services/heapDumper.hpp"
64 #include "services/heapDumperCompression.hpp"
65 #include "services/threadService.hpp"
66 #include "utilities/checkedCast.hpp"
67 #include "utilities/macros.hpp"
68 #include "utilities/ostream.hpp"
69 #ifdef LINUX
70 #include "os_linux.hpp"
302 * 7: double array
303 * 8: byte array
304 * 9: short array
305 * 10: int array
306 * 11: long array
307 * [u1]* elements
308 *
309 * HPROF_CPU_SAMPLES a set of sample traces of running threads
310 *
311 * u4 total number of samples
312 * u4 # of traces
313 * [u4 # of samples
314 * u4]* stack trace serial number
315 *
316 * HPROF_CONTROL_SETTINGS the settings of on/off switches
317 *
318 * u4 0x00000001: alloc traces on/off
319 * 0x00000002: cpu sampling on/off
320 * u2 stack trace depth
321 *
322 * HPROF_FLAT_ARRAYS list of flat arrays
323 *
324 * [flat array sub-records]*
325 *
326 * HPROF_FLAT_ARRAY flat array
327 *
328 * id array object ID (dumped as HPROF_GC_PRIM_ARRAY_DUMP)
329 * id element class ID (dumped by HPROF_GC_CLASS_DUMP)
330 *
331 * HPROF_INLINED_FIELDS decribes inlined fields
332 *
333 * [class with inlined fields sub-records]*
334 *
335 * HPROF_CLASS_WITH_INLINED_FIELDS
336 *
337 * id class ID (dumped as HPROF_GC_CLASS_DUMP)
338 *
339 * u2 number of instance inlined fields (not including super)
340 * [u2, inlined field index,
341 * u2, synthetic field count,
342 * id, original field name,
343 * id]* inlined field class ID (dumped by HPROF_GC_CLASS_DUMP)
344 *
345 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
346 * be generated as a sequence of heap dump segments. This sequence is
347 * terminated by an end record. The additional tags allowed by format
348 * "JAVA PROFILE 1.0.2" are:
349 *
350 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
351 *
352 * [heap dump sub-records]*
353 * The same sub-record types allowed by HPROF_HEAP_DUMP
354 *
355 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
356 *
357 */
358
359
360 // HPROF tags
361
362 enum hprofTag : u1 {
363 // top-level records
364 HPROF_UTF8 = 0x01,
365 HPROF_LOAD_CLASS = 0x02,
366 HPROF_UNLOAD_CLASS = 0x03,
367 HPROF_FRAME = 0x04,
368 HPROF_TRACE = 0x05,
369 HPROF_ALLOC_SITES = 0x06,
370 HPROF_HEAP_SUMMARY = 0x07,
371 HPROF_START_THREAD = 0x0A,
372 HPROF_END_THREAD = 0x0B,
373 HPROF_HEAP_DUMP = 0x0C,
374 HPROF_CPU_SAMPLES = 0x0D,
375 HPROF_CONTROL_SETTINGS = 0x0E,
376
377 // 1.0.2 record types
378 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
379 HPROF_HEAP_DUMP_END = 0x2C,
380
381 // inlined object support
382 HPROF_FLAT_ARRAYS = 0x12,
383 HPROF_INLINED_FIELDS = 0x13,
384 // inlined object subrecords
385 HPROF_FLAT_ARRAY = 0x01,
386 HPROF_CLASS_WITH_INLINED_FIELDS = 0x01,
387
388 // field types
389 HPROF_ARRAY_OBJECT = 0x01,
390 HPROF_NORMAL_OBJECT = 0x02,
391 HPROF_BOOLEAN = 0x04,
392 HPROF_CHAR = 0x05,
393 HPROF_FLOAT = 0x06,
394 HPROF_DOUBLE = 0x07,
395 HPROF_BYTE = 0x08,
396 HPROF_SHORT = 0x09,
397 HPROF_INT = 0x0A,
398 HPROF_LONG = 0x0B,
399
400 // data-dump sub-records
401 HPROF_GC_ROOT_UNKNOWN = 0xFF,
402 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
403 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
404 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
405 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
406 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
407 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
408 HPROF_GC_ROOT_MONITOR_USED = 0x07,
409 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
410 HPROF_GC_CLASS_DUMP = 0x20,
411 HPROF_GC_INSTANCE_DUMP = 0x21,
412 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
413 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
414 };
415
416 // Default stack trace ID (used for dummy HPROF_TRACE record)
417 enum {
418 STACK_TRACE_ID = 1,
419 INITIAL_CLASS_COUNT = 200
420 };
421
422
423 class AbstractDumpWriter;
424
425 class InlinedObjects {
426
427 struct ClassInlinedFields {
428 const Klass *klass;
429 uintx base_index; // base index of the inlined field names (1st field has index base_index+1).
430 ClassInlinedFields(const Klass *klass = nullptr, uintx base_index = 0) : klass(klass), base_index(base_index) {}
431
432 // For GrowableArray::find_sorted().
433 static int compare(const ClassInlinedFields& a, const ClassInlinedFields& b) {
434 return a.klass - b.klass;
435 }
436 // For GrowableArray::sort().
437 static int compare(ClassInlinedFields* a, ClassInlinedFields* b) {
438 return compare(*a, *b);
439 }
440 };
441
442 uintx _min_string_id;
443 uintx _max_string_id;
444
445 GrowableArray<ClassInlinedFields> *_inlined_field_map;
446
447 // counters for classes with inlined fields and for the fields
448 int _classes_count;
449 int _inlined_fields_count;
450
451 static InlinedObjects *_instance;
452
453 static void inlined_field_names_callback(InlinedObjects* _this, const Klass *klass, uintx base_index, int count);
454
455 GrowableArray<oop> *_flat_arrays;
456
457 public:
458 InlinedObjects()
459 : _min_string_id(0), _max_string_id(0),
460 _inlined_field_map(nullptr),
461 _classes_count(0), _inlined_fields_count(0),
462 _flat_arrays(nullptr) {
463 }
464
465 static InlinedObjects* get_instance() {
466 return _instance;
467 }
468
469 void init();
470 void release();
471
472 void dump_inlined_field_names(AbstractDumpWriter *writer);
473
474 uintx get_base_index_for(Klass* k);
475 uintx get_next_string_id(uintx id);
476
477 void dump_classed_with_inlined_fields(AbstractDumpWriter* writer);
478
479 void add_flat_array(oop array);
480 void dump_flat_arrays(AbstractDumpWriter* writer);
481
482 };
483
484 InlinedObjects *InlinedObjects::_instance = nullptr;
485
486
487 // Supports I/O operations for a dump
488 // Base class for dump and parallel dump
489 class AbstractDumpWriter : public CHeapObj<mtInternal> {
490 protected:
491 enum {
492 io_buffer_max_size = 1*M,
493 dump_segment_header_size = 9
494 };
495
496 char* _buffer; // internal buffer
497 size_t _size;
498 size_t _pos;
499
500 bool _in_dump_segment; // Are we currently in a dump segment?
501 bool _is_huge_sub_record; // Are we writing a sub-record larger than the buffer size?
502 DEBUG_ONLY(size_t _sub_record_left;) // The bytes not written for the current sub-record.
503 DEBUG_ONLY(bool _sub_record_ended;) // True if we have called the end_sub_record().
504
505 char* buffer() const { return _buffer; }
506 size_t buffer_size() const { return _size; }
819 }
820 }
821
822 class DumperClassCacheTable;
823 class DumperClassCacheTableEntry;
824
825 // Support class with a collection of functions used when dumping the heap
826 class DumperSupport : AllStatic {
827 public:
828
829 // write a header of the given type
830 static void write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len);
831
832 // returns hprof tag for the given type signature
833 static hprofTag sig2tag(Symbol* sig);
834 // returns hprof tag for the given basic type
835 static hprofTag type2tag(BasicType type);
836 // Returns the size of the data to write.
837 static u4 sig2size(Symbol* sig);
838
839 // calculates the total size of the all fields of the given class.
840 static u4 instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry = nullptr);
841
842 // dump a jfloat
843 static void dump_float(AbstractDumpWriter* writer, jfloat f);
844 // dump a jdouble
845 static void dump_double(AbstractDumpWriter* writer, jdouble d);
846 // dumps the raw value of the given field
847 static void dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset);
848 // returns the size of the static fields; also counts the static fields
849 static u4 get_static_fields_size(InstanceKlass* ik, u2& field_count);
850 // dumps static fields of the given class
851 static void dump_static_fields(AbstractDumpWriter* writer, Klass* k);
852 // dump the raw values of the instance fields of the given identity or inlined object;
853 // for identity objects offset is 0 and 'klass' is o->klass(),
854 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class
855 static void dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry);
856 // dump the raw values of the instance fields of the given inlined object;
857 // dump_instance_fields wrapper for inlined objects
858 static void dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry);
859
860 // get the count of the instance fields for a given class
861 static u2 get_instance_fields_count(InstanceKlass* ik);
862 // dumps the definition of the instance fields for a given class
863 static void dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* k, uintx *inlined_fields_index = nullptr);
864 // creates HPROF_GC_INSTANCE_DUMP record for the given object
865 static void dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache);
866 // creates HPROF_GC_CLASS_DUMP record for the given instance class
867 static void dump_instance_class(AbstractDumpWriter* writer, Klass* k);
868 // creates HPROF_GC_CLASS_DUMP record for a given array class
869 static void dump_array_class(AbstractDumpWriter* writer, Klass* k);
870
871 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
872 static void dump_object_array(AbstractDumpWriter* writer, objArrayOop array);
873 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
874 static void dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache);
875 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
876 static void dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array);
877 // create HPROF_FRAME record for the given method and bci
878 static void dump_stack_frame(AbstractDumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
879
880 // check if we need to truncate an array
881 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size);
882 // extended version to dump flat arrays as primitive arrays;
883 // type_size specifies size of the inlined objects.
884 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size);
885
886 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
887 static void end_of_dump(AbstractDumpWriter* writer);
888
889 static oop mask_dormant_archived_object(oop o, oop ref_obj) {
890 if (o != nullptr && o->klass()->java_mirror_no_keepalive() == nullptr) {
891 // Ignore this object since the corresponding java mirror is not loaded.
892 // Might be a dormant archive object.
893 report_dormant_archived_object(o, ref_obj);
894 return nullptr;
895 } else {
896 return o;
897 }
898 }
899
900 // helper methods for inlined fields.
901 static bool is_inlined_field(const fieldDescriptor& fld) {
902 return fld.is_flat();
903 }
904 static InlineKlass* get_inlined_field_klass(const fieldDescriptor& fld) {
905 assert(is_inlined_field(fld), "must be inlined field");
906 InstanceKlass* holder_klass = fld.field_holder();
907 return InlineKlass::cast(holder_klass->get_inline_type_field_klass(fld.index()));
908 }
909
910 static void report_dormant_archived_object(oop o, oop ref_obj) {
911 if (log_is_enabled(Trace, cds, heap)) {
912 ResourceMark rm;
913 if (ref_obj != nullptr) {
914 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)",
915 p2i(o), o->klass()->external_name(),
916 p2i(ref_obj), ref_obj->klass()->external_name());
917 } else {
918 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s)",
919 p2i(o), o->klass()->external_name());
920 }
921 }
922 }
923 };
924
925 // Hash table of klasses to the klass metadata. This should greatly improve the
926 // hash dumping performance. This hash table is supposed to be used by a single
927 // thread only.
928 //
929 class DumperClassCacheTableEntry : public CHeapObj<mtServiceability> {
930 friend class DumperClassCacheTable;
931 private:
932 GrowableArray<char> _sigs_start;
933 GrowableArray<int> _offsets;
934 GrowableArray<InlineKlass*> _inline_klasses;
935 u4 _instance_size;
936 int _entries;
937
938 public:
939 DumperClassCacheTableEntry() : _instance_size(0), _entries(0) {};
940
941 int field_count() { return _entries; }
942 char sig_start(int field_idx) { return _sigs_start.at(field_idx); }
943 void push_sig_start_inlined() { _sigs_start.push('Q'); }
944 bool is_inlined(int field_idx){ return _sigs_start.at(field_idx) == 'Q'; }
945 InlineKlass* inline_klass(int field_idx) { assert(is_inlined(field_idx), "Not inlined"); return _inline_klasses.at(field_idx); }
946 int offset(int field_idx) { return _offsets.at(field_idx); }
947 u4 instance_size() { return _instance_size; }
948 };
949
950 class DumperClassCacheTable {
951 private:
952 // ResourceHashtable SIZE is specified at compile time so we
953 // use 1031 which is the first prime after 1024.
954 static constexpr size_t TABLE_SIZE = 1031;
955
956 // Maintain the cache for N classes. This limits memory footprint
957 // impact, regardless of how many classes we have in the dump.
958 // This also improves look up performance by keeping the statically
959 // sized table from overloading.
960 static constexpr int CACHE_TOP = 256;
961
962 typedef ResourceHashtable<InstanceKlass*, DumperClassCacheTableEntry*,
963 TABLE_SIZE, AnyObj::C_HEAP, mtServiceability> PtrTable;
964 PtrTable* _ptrs;
965
974 bool do_entry(InstanceKlass*& key, DumperClassCacheTableEntry*& entry) {
975 delete entry;
976 return true;
977 }
978 } cleanup;
979 table->unlink(&cleanup);
980 }
981
982 public:
983 DumperClassCacheTableEntry* lookup_or_create(InstanceKlass* ik) {
984 if (_last_ik == ik) {
985 return _last_entry;
986 }
987
988 DumperClassCacheTableEntry* entry;
989 DumperClassCacheTableEntry** from_cache = _ptrs->get(ik);
990 if (from_cache == nullptr) {
991 entry = new DumperClassCacheTableEntry();
992 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
993 if (!fld.access_flags().is_static()) {
994 InlineKlass* inlineKlass = nullptr;
995 if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
996 inlineKlass = DumperSupport::get_inlined_field_klass(fld.field_descriptor());
997 entry->push_sig_start_inlined();
998 entry->_instance_size += DumperSupport::instance_size(inlineKlass);
999 } else {
1000 Symbol* sig = fld.signature();
1001 entry->_sigs_start.push(sig->char_at(0));
1002 entry->_instance_size += DumperSupport::sig2size(sig);
1003 }
1004 entry->_inline_klasses.push(inlineKlass);
1005 entry->_offsets.push(fld.offset());
1006 entry->_entries++;
1007 }
1008 }
1009
1010 if (_ptrs->number_of_entries() >= CACHE_TOP) {
1011 // We do not track the individual hit rates for table entries.
1012 // Purge the entire table, and let the cache catch up with new
1013 // distribution.
1014 unlink_all(_ptrs);
1015 }
1016
1017 _ptrs->put(ik, entry);
1018 } else {
1019 entry = *from_cache;
1020 }
1021
1022 // Remember for single-slot cache.
1023 _last_ik = ik;
1024 _last_entry = entry;
1025
1026 return entry;
1096 }
1097
1098 // dump a jfloat
1099 void DumperSupport::dump_float(AbstractDumpWriter* writer, jfloat f) {
1100 if (g_isnan(f)) {
1101 writer->write_u4(0x7fc00000); // collapsing NaNs
1102 } else {
1103 writer->write_u4(bit_cast<u4>(f));
1104 }
1105 }
1106
1107 // dump a jdouble
1108 void DumperSupport::dump_double(AbstractDumpWriter* writer, jdouble d) {
1109 if (g_isnan(d)) {
1110 writer->write_u8(0x7ff80000ull << 32); // collapsing NaNs
1111 } else {
1112 writer->write_u8(bit_cast<u8>(d));
1113 }
1114 }
1115
1116
1117 // dumps the raw value of the given field
1118 void DumperSupport::dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset) {
1119 switch (type) {
1120 case JVM_SIGNATURE_CLASS :
1121 case JVM_SIGNATURE_ARRAY : {
1122 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF | AS_NO_KEEPALIVE>(offset);
1123 o = mask_dormant_archived_object(o, obj);
1124 assert(oopDesc::is_oop_or_null(o), "Expected an oop or nullptr at " PTR_FORMAT, p2i(o));
1125 writer->write_objectID(o);
1126 break;
1127 }
1128 case JVM_SIGNATURE_BYTE : {
1129 jbyte b = obj->byte_field(offset);
1130 writer->write_u1(b);
1131 break;
1132 }
1133 case JVM_SIGNATURE_CHAR : {
1134 jchar c = obj->char_field(offset);
1135 writer->write_u2(c);
1136 break;
1155 writer->write_u4(i);
1156 break;
1157 }
1158 case JVM_SIGNATURE_LONG : {
1159 jlong l = obj->long_field(offset);
1160 writer->write_u8(l);
1161 break;
1162 }
1163 case JVM_SIGNATURE_BOOLEAN : {
1164 jboolean b = obj->bool_field(offset);
1165 writer->write_u1(b);
1166 break;
1167 }
1168 default : {
1169 ShouldNotReachHere();
1170 break;
1171 }
1172 }
1173 }
1174
1175 // calculates the total size of the all fields of the given class.
1176 u4 DumperSupport::instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry) {
1177 if (class_cache_entry != nullptr) {
1178 return class_cache_entry->instance_size();
1179 } else {
1180 u4 size = 0;
1181 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
1182 if (!fld.access_flags().is_static()) {
1183 if (is_inlined_field(fld.field_descriptor())) {
1184 size += instance_size(get_inlined_field_klass(fld.field_descriptor()));
1185 } else {
1186 size += sig2size(fld.signature());
1187 }
1188 }
1189 }
1190 return size;
1191 }
1192 }
1193
1194 u4 DumperSupport::get_static_fields_size(InstanceKlass* ik, u2& field_count) {
1195 field_count = 0;
1196 u4 size = 0;
1197
1198 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
1199 if (fldc.access_flags().is_static()) {
1200 assert(!is_inlined_field(fldc.field_descriptor()), "static fields cannot be inlined");
1201
1202 field_count++;
1203 size += sig2size(fldc.signature());
1204 }
1205 }
1206
1207 // Add in resolved_references which is referenced by the cpCache
1208 // The resolved_references is an array per InstanceKlass holding the
1209 // strings and other oops resolved from the constant pool.
1210 oop resolved_references = ik->constants()->resolved_references_or_null();
1211 if (resolved_references != nullptr) {
1212 field_count++;
1213 size += sizeof(address);
1214
1215 // Add in the resolved_references of the used previous versions of the class
1216 // in the case of RedefineClasses
1217 InstanceKlass* prev = ik->previous_versions();
1218 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1219 field_count++;
1220 size += sizeof(address);
1221 prev = prev->previous_versions();
1222 }
1223 }
1224
1225 // We write the value itself plus a name and a one byte type tag per field.
1226 return checked_cast<u4>(size + field_count * (sizeof(address) + 1));
1227 }
1228
1229 // dumps static fields of the given class
1230 void DumperSupport::dump_static_fields(AbstractDumpWriter* writer, Klass* k) {
1231 InstanceKlass* ik = InstanceKlass::cast(k);
1232
1233 // dump the field descriptors and raw values
1234 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
1235 if (fld.access_flags().is_static()) {
1236 assert(!is_inlined_field(fld.field_descriptor()), "static fields cannot be inlined");
1237
1238 Symbol* sig = fld.signature();
1239
1240 writer->write_symbolID(fld.name()); // name
1241 writer->write_u1(sig2tag(sig)); // type
1242
1243 // value
1244 dump_field_value(writer, sig->char_at(0), ik->java_mirror(), fld.offset());
1245 }
1246 }
1247
1248 // Add resolved_references for each class that has them
1249 oop resolved_references = ik->constants()->resolved_references_or_null();
1250 if (resolved_references != nullptr) {
1251 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1252 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1253 writer->write_objectID(resolved_references);
1254
1255 // Also write any previous versions
1256 InstanceKlass* prev = ik->previous_versions();
1257 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1258 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1259 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1260 writer->write_objectID(prev->constants()->resolved_references());
1261 prev = prev->previous_versions();
1262 }
1263 }
1264 }
1265
1266 // dump the raw values of the instance fields of the given identity or inlined object;
1267 // for identity objects offset is 0 and 'klass' is o->klass(),
1268 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class.
1269 void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) {
1270 assert(class_cache_entry != nullptr, "Pre-condition: must be provided");
1271 for (int idx = 0; idx < class_cache_entry->field_count(); idx++) {
1272 if (class_cache_entry->is_inlined(idx)) {
1273 InlineKlass* field_klass = class_cache_entry->inline_klass(idx);
1274 int fields_offset = offset + (class_cache_entry->offset(idx) - field_klass->first_field_offset());
1275 DumperClassCacheTableEntry* inline_class_cache_entry = class_cache->lookup_or_create(field_klass);
1276 dump_inlined_object_fields(writer, o, fields_offset, class_cache, inline_class_cache_entry);
1277 } else {
1278 dump_field_value(writer, class_cache_entry->sig_start(idx), o, class_cache_entry->offset(idx));
1279 }
1280 }
1281 }
1282
1283 void DumperSupport::dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) {
1284 // the object is inlined, so all its fields are stored without headers.
1285 dump_instance_fields(writer, o, offset, class_cache, class_cache_entry);
1286 }
1287
1288 // gets the count of the instance fields for a given class
1289 u2 DumperSupport::get_instance_fields_count(InstanceKlass* ik) {
1290 u2 field_count = 0;
1291
1292 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
1293 if (!fldc.access_flags().is_static()) {
1294 if (is_inlined_field(fldc.field_descriptor())) {
1295 // add "synthetic" fields for inlined fields.
1296 field_count += get_instance_fields_count(get_inlined_field_klass(fldc.field_descriptor()));
1297 } else {
1298 field_count++;
1299 }
1300 }
1301 }
1302
1303 return field_count;
1304 }
1305
1306 // dumps the definition of the instance fields for a given class
1307 // inlined_fields_id is not-nullptr for inlined fields (to get synthetic field name IDs
1308 // by using InlinedObjects::get_next_string_id()).
1309 void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* ik, uintx* inlined_fields_id) {
1310 // inlined_fields_id != nullptr means ik is a class of inlined field.
1311 // Inlined field id pointer for this class; lazyly initialized
1312 // if the class has inlined field(s) and the caller didn't provide inlined_fields_id.
1313 uintx *this_klass_inlined_fields_id = inlined_fields_id;
1314 uintx inlined_id = 0;
1315
1316 // dump the field descriptors
1317 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
1318 if (!fld.access_flags().is_static()) {
1319 if (is_inlined_field(fld.field_descriptor())) {
1320 // dump "synthetic" fields for inlined fields.
1321 if (this_klass_inlined_fields_id == nullptr) {
1322 inlined_id = InlinedObjects::get_instance()->get_base_index_for(ik);
1323 this_klass_inlined_fields_id = &inlined_id;
1324 }
1325 dump_instance_field_descriptors(writer, get_inlined_field_klass(fld.field_descriptor()), this_klass_inlined_fields_id);
1326 } else {
1327 Symbol* sig = fld.signature();
1328 Symbol* name = nullptr;
1329 // Use inlined_fields_id provided by caller.
1330 if (inlined_fields_id != nullptr) {
1331 uintx name_id = InlinedObjects::get_instance()->get_next_string_id(*inlined_fields_id);
1332
1333 // name_id == 0 is returned on error. use original field signature.
1334 if (name_id != 0) {
1335 *inlined_fields_id = name_id;
1336 name = reinterpret_cast<Symbol*>(name_id);
1337 }
1338 }
1339 if (name == nullptr) {
1340 name = fld.name();
1341 }
1342
1343 writer->write_symbolID(name); // name
1344 writer->write_u1(sig2tag(sig)); // type
1345 }
1346 }
1347 }
1348 }
1349
1350 // creates HPROF_GC_INSTANCE_DUMP record for the given object
1351 void DumperSupport::dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache) {
1352 InstanceKlass* ik = InstanceKlass::cast(o->klass());
1353
1354 DumperClassCacheTableEntry* cache_entry = class_cache->lookup_or_create(ik);
1355
1356 u4 is = instance_size(ik, cache_entry);
1357 u4 size = 1 + sizeof(address) + 4 + sizeof(address) + 4 + is;
1358
1359 writer->start_sub_record(HPROF_GC_INSTANCE_DUMP, size);
1360 writer->write_objectID(o);
1361 writer->write_u4(STACK_TRACE_ID);
1362
1363 // class ID
1364 writer->write_classID(ik);
1365
1366 // number of bytes that follow
1367 writer->write_u4(is);
1368
1369 // field values
1370 dump_instance_fields(writer, o, 0, class_cache, cache_entry);
1371
1372 writer->end_sub_record();
1373 }
1374
1375 // creates HPROF_GC_CLASS_DUMP record for the given instance class
1376 void DumperSupport::dump_instance_class(AbstractDumpWriter* writer, Klass* k) {
1377 InstanceKlass* ik = InstanceKlass::cast(k);
1378
1379 // We can safepoint and do a heap dump at a point where we have a Klass,
1380 // but no java mirror class has been setup for it. So we need to check
1381 // that the class is at least loaded, to avoid crash from a null mirror.
1382 if (!ik->is_loaded()) {
1383 return;
1384 }
1385
1386 u2 static_fields_count = 0;
1387 u4 static_size = get_static_fields_size(ik, static_fields_count);
1388 u2 instance_fields_count = get_instance_fields_count(ik);
1389 u4 instance_fields_size = instance_fields_count * (sizeof(address) + 1);
1390 u4 size = checked_cast<u4>(1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + static_size + 2 + instance_fields_size);
1395 writer->write_classID(ik);
1396 writer->write_u4(STACK_TRACE_ID);
1397
1398 // super class ID
1399 InstanceKlass* java_super = ik->java_super();
1400 if (java_super == nullptr) {
1401 writer->write_objectID(oop(nullptr));
1402 } else {
1403 writer->write_classID(java_super);
1404 }
1405
1406 writer->write_objectID(ik->class_loader());
1407 writer->write_objectID(ik->signers());
1408 writer->write_objectID(ik->protection_domain());
1409
1410 // reserved
1411 writer->write_objectID(oop(nullptr));
1412 writer->write_objectID(oop(nullptr));
1413
1414 // instance size
1415 writer->write_u4(HeapWordSize * ik->size_helper());
1416
1417 // size of constant pool - ignored by HAT 1.1
1418 writer->write_u2(0);
1419
1420 // static fields
1421 writer->write_u2(static_fields_count);
1422 dump_static_fields(writer, ik);
1423
1424 // description of instance fields
1425 writer->write_u2(instance_fields_count);
1426 dump_instance_field_descriptors(writer, ik);
1427
1428 writer->end_sub_record();
1429 }
1430
1431 // creates HPROF_GC_CLASS_DUMP record for the given array class
1432 void DumperSupport::dump_array_class(AbstractDumpWriter* writer, Klass* k) {
1433 InstanceKlass* ik = nullptr; // bottom class for object arrays, null for primitive type arrays
1434 if (k->is_objArray_klass()) {
1435 Klass *bk = ObjArrayKlass::cast(k)->bottom_klass();
1449 assert(java_super != nullptr, "checking");
1450 writer->write_classID(java_super);
1451
1452 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->class_loader());
1453 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->signers());
1454 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->protection_domain());
1455
1456 writer->write_objectID(oop(nullptr)); // reserved
1457 writer->write_objectID(oop(nullptr));
1458 writer->write_u4(0); // instance size
1459 writer->write_u2(0); // constant pool
1460 writer->write_u2(0); // static fields
1461 writer->write_u2(0); // instance fields
1462
1463 writer->end_sub_record();
1464
1465 }
1466
1467 // Hprof uses an u4 as record length field,
1468 // which means we need to truncate arrays that are too long.
1469 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size) {
1470 int length = array->length();
1471
1472 size_t length_in_bytes = (size_t)length * type_size;
1473 uint max_bytes = max_juint - header_size;
1474
1475 if (length_in_bytes > max_bytes) {
1476 length = max_bytes / type_size;
1477 length_in_bytes = (size_t)length * type_size;
1478
1479 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1480 warning("cannot dump array of type %s[] with length %d; truncating to length %d",
1481 type2name_tab[type], array->length(), length);
1482 }
1483 return length;
1484 }
1485
1486 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) {
1487 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1488 assert((type >= T_BOOLEAN && type <= T_OBJECT) || type == T_PRIMITIVE_OBJECT, "invalid array element type");
1489 int type_size;
1490 if (type == T_OBJECT) {
1491 type_size = sizeof(address);
1492 } else if (type == T_PRIMITIVE_OBJECT) {
1493 // TODO: FIXME
1494 fatal("Not supported yet"); // FIXME: JDK-8325678
1495 } else {
1496 type_size = type2aelembytes(type);
1497 }
1498
1499 return calculate_array_max_length(writer, array, type_size, header_size);
1500 }
1501
1502 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1503 void DumperSupport::dump_object_array(AbstractDumpWriter* writer, objArrayOop array) {
1504 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
1505 short header_size = 1 + 2 * 4 + 2 * sizeof(address);
1506 int length = calculate_array_max_length(writer, array, header_size);
1507 u4 size = checked_cast<u4>(header_size + length * sizeof(address));
1508
1509 writer->start_sub_record(HPROF_GC_OBJ_ARRAY_DUMP, size);
1510 writer->write_objectID(array);
1511 writer->write_u4(STACK_TRACE_ID);
1512 writer->write_u4(length);
1513
1514 // array class ID
1515 writer->write_classID(array->klass());
1516
1517 // [id]* elements
1518 for (int index = 0; index < length; index++) {
1519 oop o = array->obj_at(index);
1520 o = mask_dormant_archived_object(o, array);
1521 writer->write_objectID(o);
1522 }
1523
1524 writer->end_sub_record();
1525 }
1526
1527 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
1528 void DumperSupport::dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache) {
1529 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
1530 InlineKlass* element_klass = array_klass->element_klass();
1531 int element_size = instance_size(element_klass);
1532 /* id array object ID
1533 * u4 stack trace serial number
1534 * u4 number of elements
1535 * u1 element type
1536 */
1537 short header_size = 1 + sizeof(address) + 2 * 4 + 1;
1538
1539 // TODO: use T_SHORT/T_INT/T_LONG if needed to avoid truncation
1540 BasicType type = T_BYTE;
1541 int type_size = type2aelembytes(type);
1542 int length = calculate_array_max_length(writer, array, element_size, header_size);
1543 u4 length_in_bytes = (u4)(length * element_size);
1544 u4 size = header_size + length_in_bytes;
1545
1546 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
1547 writer->write_objectID(array);
1548 writer->write_u4(STACK_TRACE_ID);
1549 // TODO: round up array length for T_SHORT/T_INT/T_LONG
1550 writer->write_u4(length * element_size);
1551 writer->write_u1(type2tag(type));
1552
1553 for (int index = 0; index < length; index++) {
1554 // need offset in the holder to read inlined object. calculate it from flatArrayOop::value_at_addr()
1555 int offset = (int)((address)array->value_at_addr(index, array_klass->layout_helper())
1556 - cast_from_oop<address>(array));
1557 DumperClassCacheTableEntry* class_cache_entry = class_cache->lookup_or_create(element_klass);
1558 dump_inlined_object_fields(writer, array, offset, class_cache, class_cache_entry);
1559 }
1560
1561 // TODO: write padding bytes for T_SHORT/T_INT/T_LONG
1562
1563 InlinedObjects::get_instance()->add_flat_array(array);
1564
1565 writer->end_sub_record();
1566 }
1567
1568 #define WRITE_ARRAY(Array, Type, Size, Length) \
1569 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
1570
1571 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1572 void DumperSupport::dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array) {
1573 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1574 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID)
1575 short header_size = 2 * 1 + 2 * 4 + sizeof(address);
1576
1577 int length = calculate_array_max_length(writer, array, header_size);
1578 int type_size = type2aelembytes(type);
1579 u4 length_in_bytes = (u4)length * type_size;
1580 u4 size = header_size + length_in_bytes;
1581
1582 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
1583 writer->write_objectID(array);
1584 writer->write_u4(STACK_TRACE_ID);
1585 writer->write_u4(length);
1586 writer->write_u1(type2tag(type));
1587
1669 int bci) {
1670 int line_number;
1671 if (m->is_native()) {
1672 line_number = -3; // native frame
1673 } else {
1674 line_number = m->line_number_from_bci(bci);
1675 }
1676
1677 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1678 writer->write_id(frame_serial_num); // frame serial number
1679 writer->write_symbolID(m->name()); // method's name
1680 writer->write_symbolID(m->signature()); // method's signature
1681
1682 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass");
1683 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1684 writer->write_u4(class_serial_num); // class serial number
1685 writer->write_u4((u4) line_number); // line number
1686 }
1687
1688
1689 class InlinedFieldNameDumper : public LockedClassesDo {
1690 public:
1691 typedef void (*Callback)(InlinedObjects *owner, const Klass *klass, uintx base_index, int count);
1692
1693 private:
1694 AbstractDumpWriter* _writer;
1695 InlinedObjects *_owner;
1696 Callback _callback;
1697 uintx _index;
1698
1699 void dump_inlined_field_names(GrowableArray<Symbol*>* super_names, Symbol* field_name, InlineKlass* klass) {
1700 super_names->push(field_name);
1701 for (HierarchicalFieldStream<JavaFieldStream> fld(klass); !fld.done(); fld.next()) {
1702 if (!fld.access_flags().is_static()) {
1703 if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
1704 dump_inlined_field_names(super_names, fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
1705 } else {
1706 // get next string ID.
1707 uintx next_index = _owner->get_next_string_id(_index);
1708 if (next_index == 0) {
1709 // something went wrong (overflow?)
1710 // stop generation; the rest of inlined objects will have original field names.
1711 return;
1712 }
1713 _index = next_index;
1714
1715 // Calculate length.
1716 int len = fld.name()->utf8_length();
1717 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
1718 len += (*it)->utf8_length() + 1; // +1 for ".".
1719 }
1720
1721 DumperSupport::write_header(_writer, HPROF_UTF8, oopSize + len);
1722 _writer->write_symbolID(reinterpret_cast<Symbol*>(_index));
1723 // Write the string value.
1724 // 1) super_names.
1725 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
1726 _writer->write_raw((*it)->bytes(), (*it)->utf8_length());
1727 _writer->write_u1('.');
1728 }
1729 // 2) field name.
1730 _writer->write_raw(fld.name()->bytes(), fld.name()->utf8_length());
1731 }
1732 }
1733 }
1734 super_names->pop();
1735 }
1736
1737 void dump_inlined_field_names(Symbol* field_name, InlineKlass* field_klass) {
1738 GrowableArray<Symbol*> super_names(4, mtServiceability);
1739 dump_inlined_field_names(&super_names, field_name, field_klass);
1740 }
1741
1742 public:
1743 InlinedFieldNameDumper(AbstractDumpWriter* writer, InlinedObjects* owner, Callback callback)
1744 : _writer(writer), _owner(owner), _callback(callback), _index(0) {
1745 }
1746
1747 void do_klass(Klass* k) {
1748 if (!k->is_instance_klass()) {
1749 return;
1750 }
1751 InstanceKlass* ik = InstanceKlass::cast(k);
1752 // if (ik->has_inline_type_fields()) {
1753 // return;
1754 // }
1755
1756 uintx base_index = _index;
1757 int count = 0;
1758
1759 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
1760 if (!fld.access_flags().is_static()) {
1761 if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
1762 dump_inlined_field_names(fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
1763 count++;
1764 }
1765 }
1766 }
1767
1768 if (count != 0) {
1769 _callback(_owner, k, base_index, count);
1770 }
1771 }
1772 };
1773
1774 class InlinedFieldsDumper : public LockedClassesDo {
1775 private:
1776 AbstractDumpWriter* _writer;
1777
1778 public:
1779 InlinedFieldsDumper(AbstractDumpWriter* writer) : _writer(writer) {}
1780
1781 void do_klass(Klass* k) {
1782 if (!k->is_instance_klass()) {
1783 return;
1784 }
1785 InstanceKlass* ik = InstanceKlass::cast(k);
1786 // if (ik->has_inline_type_fields()) {
1787 // return;
1788 // }
1789
1790 // We can be at a point where java mirror does not exist yet.
1791 // So we need to check that the class is at least loaded, to avoid crash from a null mirror.
1792 if (!ik->is_loaded()) {
1793 return;
1794 }
1795
1796 u2 inlined_count = 0;
1797 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
1798 if (!fld.access_flags().is_static()) {
1799 if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
1800 inlined_count++;
1801 }
1802 }
1803 }
1804 if (inlined_count != 0) {
1805 _writer->write_u1(HPROF_CLASS_WITH_INLINED_FIELDS);
1806
1807 // class ID
1808 _writer->write_classID(ik);
1809 // number of inlined fields
1810 _writer->write_u2(inlined_count);
1811 u2 index = 0;
1812 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
1813 if (!fld.access_flags().is_static()) {
1814 if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
1815 // inlined field index
1816 _writer->write_u2(index);
1817 // synthetic field count
1818 u2 field_count = DumperSupport::get_instance_fields_count(DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
1819 _writer->write_u2(field_count);
1820 // original field name
1821 _writer->write_symbolID(fld.name());
1822 // inlined field class ID
1823 _writer->write_classID(DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
1824
1825 index += field_count;
1826 } else {
1827 index++;
1828 }
1829 }
1830 }
1831 }
1832 }
1833 };
1834
1835
1836 void InlinedObjects::init() {
1837 _instance = this;
1838
1839 struct Closure : public SymbolClosure {
1840 uintx _min_id = max_uintx;
1841 uintx _max_id = 0;
1842 Closure() : _min_id(max_uintx), _max_id(0) {}
1843
1844 void do_symbol(Symbol** p) {
1845 uintx val = reinterpret_cast<uintx>(*p);
1846 if (val < _min_id) {
1847 _min_id = val;
1848 }
1849 if (val > _max_id) {
1850 _max_id = val;
1851 }
1852 }
1853 } closure;
1854
1855 SymbolTable::symbols_do(&closure);
1856
1857 _min_string_id = closure._min_id;
1858 _max_string_id = closure._max_id;
1859 }
1860
1861 void InlinedObjects::release() {
1862 _instance = nullptr;
1863
1864 if (_inlined_field_map != nullptr) {
1865 delete _inlined_field_map;
1866 _inlined_field_map = nullptr;
1867 }
1868 if (_flat_arrays != nullptr) {
1869 delete _flat_arrays;
1870 _flat_arrays = nullptr;
1871 }
1872 }
1873
1874 void InlinedObjects::inlined_field_names_callback(InlinedObjects* _this, const Klass* klass, uintx base_index, int count) {
1875 if (_this->_inlined_field_map == nullptr) {
1876 _this->_inlined_field_map = new (mtServiceability) GrowableArray<ClassInlinedFields>(100, mtServiceability);
1877 }
1878 _this->_inlined_field_map->append(ClassInlinedFields(klass, base_index));
1879
1880 // counters for dumping classes with inlined fields
1881 _this->_classes_count++;
1882 _this->_inlined_fields_count += count;
1883 }
1884
1885 void InlinedObjects::dump_inlined_field_names(AbstractDumpWriter* writer) {
1886 InlinedFieldNameDumper nameDumper(writer, this, inlined_field_names_callback);
1887 ClassLoaderDataGraph::classes_do(&nameDumper);
1888
1889 if (_inlined_field_map != nullptr) {
1890 // prepare the map for get_base_index_for().
1891 _inlined_field_map->sort(ClassInlinedFields::compare);
1892 }
1893 }
1894
1895 uintx InlinedObjects::get_base_index_for(Klass* k) {
1896 if (_inlined_field_map != nullptr) {
1897 bool found = false;
1898 int idx = _inlined_field_map->find_sorted<ClassInlinedFields, ClassInlinedFields::compare>(ClassInlinedFields(k, 0), found);
1899 if (found) {
1900 return _inlined_field_map->at(idx).base_index;
1901 }
1902 }
1903
1904 // return max_uintx, so get_next_string_id returns 0.
1905 return max_uintx;
1906 }
1907
1908 uintx InlinedObjects::get_next_string_id(uintx id) {
1909 if (++id == _min_string_id) {
1910 return _max_string_id + 1;
1911 }
1912 return id;
1913 }
1914
1915 void InlinedObjects::dump_classed_with_inlined_fields(AbstractDumpWriter* writer) {
1916 if (_classes_count != 0) {
1917 // Record for each class contains tag(u1), class ID and count(u2)
1918 // for each inlined field index(u2), synthetic fields count(u2), original field name and class ID
1919 int size = _classes_count * (1 + sizeof(address) + 2)
1920 + _inlined_fields_count * (2 + 2 + sizeof(address) + sizeof(address));
1921 DumperSupport::write_header(writer, HPROF_INLINED_FIELDS, (u4)size);
1922
1923 InlinedFieldsDumper dumper(writer);
1924 ClassLoaderDataGraph::classes_do(&dumper);
1925 }
1926 }
1927
1928 void InlinedObjects::add_flat_array(oop array) {
1929 if (_flat_arrays == nullptr) {
1930 _flat_arrays = new (mtServiceability) GrowableArray<oop>(100, mtServiceability);
1931 }
1932 _flat_arrays->append(array);
1933 }
1934
1935 void InlinedObjects::dump_flat_arrays(AbstractDumpWriter* writer) {
1936 if (_flat_arrays != nullptr) {
1937 // For each flat array the record contains tag (u1), object ID and class ID.
1938 int size = _flat_arrays->length() * (1 + sizeof(address) + sizeof(address));
1939
1940 DumperSupport::write_header(writer, HPROF_FLAT_ARRAYS, (u4)size);
1941 for (GrowableArrayIterator<oop> it = _flat_arrays->begin(); it != _flat_arrays->end(); ++it) {
1942 flatArrayOop array = flatArrayOop(*it);
1943 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
1944 InlineKlass* element_klass = array_klass->element_klass();
1945 writer->write_u1(HPROF_FLAT_ARRAY);
1946 writer->write_objectID(array);
1947 writer->write_classID(element_klass);
1948 }
1949 }
1950 }
1951
1952
1953 // Support class used to generate HPROF_UTF8 records from the entries in the
1954 // SymbolTable.
1955
1956 class SymbolTableDumper : public SymbolClosure {
1957 private:
1958 AbstractDumpWriter* _writer;
1959 AbstractDumpWriter* writer() const { return _writer; }
1960 public:
1961 SymbolTableDumper(AbstractDumpWriter* writer) { _writer = writer; }
1962 void do_symbol(Symbol** p);
1963 };
1964
1965 void SymbolTableDumper::do_symbol(Symbol** p) {
1966 ResourceMark rm;
1967 Symbol* sym = *p;
1968 int len = sym->utf8_length();
1969 if (len > 0) {
1970 char* s = sym->as_utf8();
1971 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1972 writer()->write_symbolID(sym);
2424 return;
2425 }
2426 }
2427
2428 if (DumperSupport::mask_dormant_archived_object(o, nullptr) == nullptr) {
2429 return;
2430 }
2431
2432 if (o->is_instance()) {
2433 // create a HPROF_GC_INSTANCE record for each object
2434 DumperSupport::dump_instance(writer(), o, &_class_cache);
2435 // If we encounter an unmounted virtual thread it needs to be dumped explicitly
2436 // (mounted virtual threads are dumped with their carriers).
2437 if (java_lang_VirtualThread::is_instance(o)
2438 && ThreadDumper::should_dump_vthread(o) && !ThreadDumper::is_vthread_mounted(o)) {
2439 _vthread_dumper->dump_vthread(o, writer());
2440 }
2441 } else if (o->is_objArray()) {
2442 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
2443 DumperSupport::dump_object_array(writer(), objArrayOop(o));
2444 } else if (o->is_flatArray()) {
2445 DumperSupport::dump_flat_array(writer(), flatArrayOop(o), &_class_cache);
2446 } else if (o->is_typeArray()) {
2447 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
2448 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
2449 }
2450 }
2451
2452 // The dumper controller for parallel heap dump
2453 class DumperController : public CHeapObj<mtInternal> {
2454 private:
2455 Monitor* _lock;
2456 Mutex* _global_writer_lock;
2457
2458 const uint _dumper_number;
2459 uint _complete_number;
2460
2461 bool _started; // VM dumper started and acquired global writer lock
2462
2463 public:
2464 DumperController(uint number) :
2465 // _lock and _global_writer_lock are used for synchronization between GC worker threads inside safepoint,
2505 _complete_number++;
2506 // propagate local error to global if any
2507 if (local_writer->has_error()) {
2508 global_writer->set_error(local_writer->error());
2509 }
2510 ml.notify();
2511 }
2512
2513 void wait_all_dumpers_complete() {
2514 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2515 while (_complete_number != _dumper_number) {
2516 ml.wait();
2517 }
2518 }
2519 };
2520
2521 // DumpMerger merges separate dump files into a complete one
2522 class DumpMerger : public StackObj {
2523 private:
2524 DumpWriter* _writer;
2525 InlinedObjects* _inlined_objects;
2526 const char* _path;
2527 bool _has_error;
2528 int _dump_seq;
2529
2530 private:
2531 void merge_file(const char* path);
2532 void merge_done();
2533 void set_error(const char* msg);
2534
2535 public:
2536 DumpMerger(const char* path, DumpWriter* writer, InlinedObjects* inlined_objects, int dump_seq) :
2537 _writer(writer),
2538 _inlined_objects(inlined_objects),
2539 _path(path),
2540 _has_error(_writer->has_error()),
2541 _dump_seq(dump_seq) {}
2542
2543 void do_merge();
2544
2545 // returns path for the parallel DumpWriter (resource allocated)
2546 static char* get_writer_path(const char* base_path, int seq);
2547
2548 };
2549
2550 char* DumpMerger::get_writer_path(const char* base_path, int seq) {
2551 // approximate required buffer size
2552 size_t buf_size = strlen(base_path)
2553 + 2 // ".p"
2554 + 10 // number (that's enough for 2^32 parallel dumpers)
2555 + 1; // '\0'
2556
2557 char* path = NEW_RESOURCE_ARRAY(char, buf_size);
2558 memset(path, 0, buf_size);
2559
2560 os::snprintf(path, buf_size, "%s.p%d", base_path, seq);
2561
2562 return path;
2563 }
2564
2565
2566 void DumpMerger::merge_done() {
2567 // Writes the HPROF_HEAP_DUMP_END record.
2568 if (!_has_error) {
2569 DumperSupport::end_of_dump(_writer);
2570 _inlined_objects->dump_flat_arrays(_writer);
2571 _writer->flush();
2572 _inlined_objects->release();
2573 }
2574 _dump_seq = 0; //reset
2575 }
2576
2577 void DumpMerger::set_error(const char* msg) {
2578 assert(msg != nullptr, "sanity check");
2579 log_error(heapdump)("%s (file: %s)", msg, _path);
2580 _writer->set_error(msg);
2581 _has_error = true;
2582 }
2583
2584 #ifdef LINUX
2585 // Merge segmented heap files via sendfile, it's more efficient than the
2586 // read+write combination, which would require transferring data to and from
2587 // user space.
2588 void DumpMerger::merge_file(const char* path) {
2589 TraceTime timer("Merge segmented heap file directly", TRACETIME_LOG(Info, heapdump));
2590
2591 int segment_fd = os::open(path, O_RDONLY, 0);
2592 if (segment_fd == -1) {
2687 }
2688 };
2689
2690 // The VM operation that performs the heap dump
2691 class VM_HeapDumper : public VM_GC_Operation, public WorkerTask, public UnmountedVThreadDumper {
2692 private:
2693 static VM_HeapDumper* _global_dumper;
2694 static DumpWriter* _global_writer;
2695 DumpWriter* _local_writer;
2696 JavaThread* _oome_thread;
2697 Method* _oome_constructor;
2698 bool _gc_before_heap_dump;
2699 GrowableArray<Klass*>* _klass_map;
2700
2701 ThreadDumper** _thread_dumpers; // platform, carrier and mounted virtual threads
2702 int _thread_dumpers_count;
2703 volatile int _thread_serial_num;
2704 volatile int _frame_serial_num;
2705
2706 volatile int _dump_seq;
2707
2708 // Inlined object support.
2709 InlinedObjects _inlined_objects;
2710
2711 // parallel heap dump support
2712 uint _num_dumper_threads;
2713 DumperController* _dumper_controller;
2714 ParallelObjectIterator* _poi;
2715
2716 // Dumper id of VMDumper thread.
2717 static const int VMDumperId = 0;
2718 // VM dumper dumps both heap and non-heap data, other dumpers dump heap-only data.
2719 static bool is_vm_dumper(int dumper_id) { return dumper_id == VMDumperId; }
2720 // the 1st dumper calling get_next_dumper_id becomes VM dumper
2721 int get_next_dumper_id() {
2722 return Atomic::fetch_then_add(&_dump_seq, 1);
2723 }
2724
2725 // accessors and setters
2726 static VM_HeapDumper* dumper() { assert(_global_dumper != nullptr, "Error"); return _global_dumper; }
2727 static DumpWriter* writer() { assert(_global_writer != nullptr, "Error"); return _global_writer; }
2728
2729 void set_global_dumper() {
2730 assert(_global_dumper == nullptr, "Error");
2791 }
2792
2793 ~VM_HeapDumper() {
2794 if (_thread_dumpers != nullptr) {
2795 for (int i = 0; i < _thread_dumpers_count; i++) {
2796 delete _thread_dumpers[i];
2797 }
2798 FREE_C_HEAP_ARRAY(ThreadDumper*, _thread_dumpers);
2799 }
2800
2801 if (_dumper_controller != nullptr) {
2802 delete _dumper_controller;
2803 _dumper_controller = nullptr;
2804 }
2805 delete _klass_map;
2806 }
2807 int dump_seq() { return _dump_seq; }
2808 bool is_parallel_dump() { return _num_dumper_threads > 1; }
2809 void prepare_parallel_dump(WorkerThreads* workers);
2810
2811 InlinedObjects* inlined_objects() { return &_inlined_objects; }
2812
2813 VMOp_Type type() const { return VMOp_HeapDumper; }
2814 virtual bool doit_prologue();
2815 void doit();
2816 void work(uint worker_id);
2817
2818 // UnmountedVThreadDumper implementation
2819 void dump_vthread(oop vt, AbstractDumpWriter* segment_writer);
2820 };
2821
2822 VM_HeapDumper* VM_HeapDumper::_global_dumper = nullptr;
2823 DumpWriter* VM_HeapDumper::_global_writer = nullptr;
2824
2825 bool VM_HeapDumper::skip_operation() const {
2826 return false;
2827 }
2828
2829 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
2830 void DumperSupport::end_of_dump(AbstractDumpWriter* writer) {
2831 writer->finish_dump_segment();
2832
2967 _dumper_controller->lock_global_writer();
2968 _dumper_controller->signal_start();
2969 } else {
2970 _dumper_controller->wait_for_start_signal();
2971 }
2972
2973 if (is_vm_dumper(dumper_id)) {
2974 TraceTime timer("Dump non-objects", TRACETIME_LOG(Info, heapdump));
2975 // Write the file header - we always use 1.0.2
2976 const char* header = "JAVA PROFILE 1.0.2";
2977
2978 // header is few bytes long - no chance to overflow int
2979 writer()->write_raw(header, strlen(header) + 1); // NUL terminated
2980 writer()->write_u4(oopSize);
2981 // timestamp is current time in ms
2982 writer()->write_u8(os::javaTimeMillis());
2983 // HPROF_UTF8 records
2984 SymbolTableDumper sym_dumper(writer());
2985 SymbolTable::symbols_do(&sym_dumper);
2986
2987 // HPROF_UTF8 records for inlined field names.
2988 inlined_objects()->init();
2989 inlined_objects()->dump_inlined_field_names(writer());
2990
2991 // HPROF_INLINED_FIELDS
2992 inlined_objects()->dump_classed_with_inlined_fields(writer());
2993
2994 // write HPROF_LOAD_CLASS records
2995 {
2996 LockedClassesDo locked_load_classes(&do_load_class);
2997 ClassLoaderDataGraph::classes_do(&locked_load_classes);
2998 }
2999
3000 // write HPROF_FRAME and HPROF_TRACE records
3001 // this must be called after _klass_map is built when iterating the classes above.
3002 dump_stack_traces(writer());
3003
3004 // unlock global writer, so parallel dumpers can dump stack traces of unmounted virtual threads
3005 _dumper_controller->unlock_global_writer();
3006 }
3007
3008 // HPROF_HEAP_DUMP/HPROF_HEAP_DUMP_SEGMENT starts here
3009
3010 ResourceMark rm;
3011 // share global compressor, local DumpWriter is not responsible for its life cycle
3012 DumpWriter segment_writer(DumpMerger::get_writer_path(writer()->get_file_path(), dumper_id),
3013 writer()->is_overwrite(), writer()->compressor());
3161 (error() != nullptr) ? error() : "reason unknown");
3162 }
3163 return -1;
3164 }
3165
3166 // generate the segmented heap dump into separate files
3167 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome, num_dump_threads);
3168 VMThread::execute(&dumper);
3169
3170 // record any error that the writer may have encountered
3171 set_error(writer.error());
3172
3173 // Heap dump process is done in two phases
3174 //
3175 // Phase 1: Concurrent threads directly write heap data to multiple heap files.
3176 // This is done by VM_HeapDumper, which is performed within safepoint.
3177 //
3178 // Phase 2: Merge multiple heap files into one complete heap dump file.
3179 // This is done by DumpMerger, which is performed outside safepoint
3180
3181 DumpMerger merger(path, &writer, dumper.inlined_objects(), dumper.dump_seq());
3182 Thread* current_thread = Thread::current();
3183 if (current_thread->is_AttachListener_thread()) {
3184 // perform heapdump file merge operation in the current thread prevents us
3185 // from occupying the VM Thread, which in turn affects the occurrence of
3186 // GC and other VM operations.
3187 merger.do_merge();
3188 } else {
3189 // otherwise, performs it by VM thread
3190 VM_HeapDumpMerge op(&merger);
3191 VMThread::execute(&op);
3192 }
3193 if (writer.error() != nullptr) {
3194 set_error(writer.error());
3195 }
3196
3197 // emit JFR event
3198 if (error() == nullptr) {
3199 event.set_destination(path);
3200 event.set_gcBeforeDump(_gc_before_heap_dump);
3201 event.set_size(writer.bytes_written());
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