jdk8-mips64-public/hotspot: src/share/vm/memory/heapInspection.cpp@2c022e432e10 (annotated)

src/share/vm/memory/heapInspection.cpp@2c022e432e10 (annotated)

src/share/vm/memory/heapInspection.cpp

Fri, 20 Sep 2013 10:53:28 +0200

author: stefank
date: Fri, 20 Sep 2013 10:53:28 +0200
changeset 5769: 2c022e432e10
parent 5307: e0c9a1d29eb4
child 6680: 78bbf4d43a14
permissions: -rw-r--r--

8024974: Incorrect use of GC_locker::is_active()
Summary: SymbolTable and StringTable can make calls to GC_locker::is_active() outside a safepoint. This isn't safe because the GC_locker active state (lock count) is only updated at a safepoint and only remains valid as long as _needs_gc is true. However, outside a safepoint_needs_gc can change to false at any time, which makes it impossible to do a correct call to is_active() in that context. In this case these calls can just be removed since the input argument to basic_add() should never be on the heap and so there's no need to check the GC_locker state. This change also adjusts the assert() in is_active() to makes sure all calls to this function are always done under a safepoint.
Reviewed-by: brutisso, dcubed
Contributed-by: per.liden@oracle.com

 /*
  * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "classfile/classLoaderData.hpp"
 #include "gc_interface/collectedHeap.hpp"
 #include "memory/genCollectedHeap.hpp"
 #include "memory/heapInspection.hpp"
 #include "memory/resourceArea.hpp"
 #include "runtime/os.hpp"
 #include "utilities/globalDefinitions.hpp"
 #include "utilities/macros.hpp"
 #if INCLUDE_ALL_GCS
 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
 #endif // INCLUDE_ALL_GCS
 // HeapInspection
 int KlassInfoEntry::compare(KlassInfoEntry* e1, KlassInfoEntry* e2) {
   if(e1->_instance_words > e2->_instance_words) {
     return -1;
   } else if(e1->_instance_words < e2->_instance_words) {
     return 1;
   }
   // Sort alphabetically, note 'Z' < '[' < 'a', but it's better to group
   // the array classes before all the instance classes.
   ResourceMark rm;
   const char* name1 = e1->klass()->external_name();
   const char* name2 = e2->klass()->external_name();
   bool d1 = (name1[0] == '[');
   bool d2 = (name2[0] == '[');
   if (d1 && !d2) {
     return -1;
   } else if (d2 && !d1) {
     return 1;
   } else {
     return strcmp(name1, name2);
   }
 }
 const char* KlassInfoEntry::name() const {
   const char* name;
   if (_klass->name() != NULL) {
     name = _klass->external_name();
   } else {
     if (_klass == Universe::boolArrayKlassObj())         name = "<boolArrayKlass>";         else
     if (_klass == Universe::charArrayKlassObj())         name = "<charArrayKlass>";         else
     if (_klass == Universe::singleArrayKlassObj())       name = "<singleArrayKlass>";       else
     if (_klass == Universe::doubleArrayKlassObj())       name = "<doubleArrayKlass>";       else
     if (_klass == Universe::byteArrayKlassObj())         name = "<byteArrayKlass>";         else
     if (_klass == Universe::shortArrayKlassObj())        name = "<shortArrayKlass>";        else
     if (_klass == Universe::intArrayKlassObj())          name = "<intArrayKlass>";          else
     if (_klass == Universe::longArrayKlassObj())         name = "<longArrayKlass>";         else
       name = "<no name>";
   }
   return name;
 }
 void KlassInfoEntry::print_on(outputStream* st) const {
   ResourceMark rm;
   // simplify the formatting (ILP32 vs LP64) - always cast the numbers to 64-bit
   st->print_cr(INT64_FORMAT_W(13) "  " UINT64_FORMAT_W(13) "  %s",
                (jlong)  _instance_count,
                (julong) _instance_words * HeapWordSize,
                name());
 }
 KlassInfoEntry* KlassInfoBucket::lookup(Klass* const k) {
   KlassInfoEntry* elt = _list;
   while (elt != NULL) {
     if (elt->is_equal(k)) {
       return elt;
     }
     elt = elt->next();
   }
   elt = new (std::nothrow) KlassInfoEntry(k, list());
   // We may be out of space to allocate the new entry.
   if (elt != NULL) {
     set_list(elt);
   }
   return elt;
 }
 void KlassInfoBucket::iterate(KlassInfoClosure* cic) {
   KlassInfoEntry* elt = _list;
   while (elt != NULL) {
     cic->do_cinfo(elt);
     elt = elt->next();
   }
 }
 void KlassInfoBucket::empty() {
   KlassInfoEntry* elt = _list;
   _list = NULL;
   while (elt != NULL) {
     KlassInfoEntry* next = elt->next();
     delete elt;
     elt = next;
   }
 }
 void KlassInfoTable::AllClassesFinder::do_klass(Klass* k) {
   // This has the SIDE EFFECT of creating a KlassInfoEntry
   // for <k>, if one doesn't exist yet.
   _table->lookup(k);
 }
 KlassInfoTable::KlassInfoTable(bool need_class_stats) {
   _size_of_instances_in_words = 0;
   _size = 0;
   _ref = (HeapWord*) Universe::boolArrayKlassObj();
   _buckets =
     (KlassInfoBucket*)  AllocateHeap(sizeof(KlassInfoBucket) * _num_buckets,
                                             mtInternal, 0, AllocFailStrategy::RETURN_NULL);
   if (_buckets != NULL) {
     _size = _num_buckets;
     for (int index = 0; index < _size; index++) {
       _buckets[index].initialize();
     }
     if (need_class_stats) {
       AllClassesFinder finder(this);
       ClassLoaderDataGraph::classes_do(&finder);
     }
   }
 }
 KlassInfoTable::~KlassInfoTable() {
   if (_buckets != NULL) {
     for (int index = 0; index < _size; index++) {
       _buckets[index].empty();
     }
     FREE_C_HEAP_ARRAY(KlassInfoBucket, _buckets, mtInternal);
     _size = 0;
   }
 }
 uint KlassInfoTable::hash(const Klass* p) {
   return (uint)(((uintptr_t)p - (uintptr_t)_ref) >> 2);
 }
 KlassInfoEntry* KlassInfoTable::lookup(Klass* k) {
   uint         idx = hash(k) % _size;
   assert(_buckets != NULL, "Allocation failure should have been caught");
   KlassInfoEntry*  e   = _buckets[idx].lookup(k);
   // Lookup may fail if this is a new klass for which we
   // could not allocate space for an new entry.
   assert(e == NULL || k == e->klass(), "must be equal");
   return e;
 }
 // Return false if the entry could not be recorded on account
 // of running out of space required to create a new entry.
 bool KlassInfoTable::record_instance(const oop obj) {
   Klass*        k = obj->klass();
   KlassInfoEntry* elt = lookup(k);
   // elt may be NULL if it's a new klass for which we
   // could not allocate space for a new entry in the hashtable.
   if (elt != NULL) {
     elt->set_count(elt->count() + 1);
     elt->set_words(elt->words() + obj->size());
     _size_of_instances_in_words += obj->size();
     return true;
   } else {
     return false;
   }
 }
 void KlassInfoTable::iterate(KlassInfoClosure* cic) {
   assert(_size == 0 || _buckets != NULL, "Allocation failure should have been caught");
   for (int index = 0; index < _size; index++) {
     _buckets[index].iterate(cic);
   }
 }
 size_t KlassInfoTable::size_of_instances_in_words() const {
   return _size_of_instances_in_words;
 }
 int KlassInfoHisto::sort_helper(KlassInfoEntry** e1, KlassInfoEntry** e2) {
   return (*e1)->compare(*e1,*e2);
 }
 KlassInfoHisto::KlassInfoHisto(KlassInfoTable* cit, const char* title) :
   _cit(cit),
   _title(title) {
   _elements = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<KlassInfoEntry*>(_histo_initial_size, true);
 }
 KlassInfoHisto::~KlassInfoHisto() {
   delete _elements;
 }
 void KlassInfoHisto::add(KlassInfoEntry* cie) {
   elements()->append(cie);
 }
 void KlassInfoHisto::sort() {
   elements()->sort(KlassInfoHisto::sort_helper);
 }
 void KlassInfoHisto::print_elements(outputStream* st) const {
   // simplify the formatting (ILP32 vs LP64) - store the sum in 64-bit
   jlong total = 0;
   julong totalw = 0;
   for(int i=0; i < elements()->length(); i++) {
     st->print("%4d: ", i+1);
     elements()->at(i)->print_on(st);
     total += elements()->at(i)->count();
     totalw += elements()->at(i)->words();
   }
   st->print_cr("Total " INT64_FORMAT_W(13) "  " UINT64_FORMAT_W(13),
                total, totalw * HeapWordSize);
 }
 #define MAKE_COL_NAME(field, name, help)     #name,
 #define MAKE_COL_HELP(field, name, help)     help,
 static const char *name_table[] = {
   HEAP_INSPECTION_COLUMNS_DO(MAKE_COL_NAME)
 };
 static const char *help_table[] = {
   HEAP_INSPECTION_COLUMNS_DO(MAKE_COL_HELP)
 };
 bool KlassInfoHisto::is_selected(const char *col_name) {
   if (_selected_columns == NULL) {
     return true;
   }
   if (strcmp(_selected_columns, col_name) == 0) {
     return true;
   }
   const char *start = strstr(_selected_columns, col_name);
   if (start == NULL) {
     return false;
   }
   // The following must be true, because _selected_columns != col_name
   if (start > _selected_columns && start[-1] != ',') {
     return false;
   }
   char x = start[strlen(col_name)];
   if (x != ',' && x != '\0') {
     return false;
   }
   return true;
 }
 void KlassInfoHisto::print_title(outputStream* st, bool csv_format,
                                  bool selected[], int width_table[],
                                  const char *name_table[]) {
   if (csv_format) {
     st->print("Index,Super");
     for (int c=0; c<KlassSizeStats::_num_columns; c++) {
        if (selected[c]) {st->print(",%s", name_table[c]);}
     }
     st->print(",ClassName");
   } else {
     st->print("Index Super");
     for (int c=0; c<KlassSizeStats::_num_columns; c++) {
       if (selected[c]) {st->print(str_fmt(width_table[c]), name_table[c]);}
     }
     st->print(" ClassName");
   }
   if (is_selected("ClassLoader")) {
     st->print(",ClassLoader");
   }
   st->cr();
 }
 void KlassInfoHisto::print_class_stats(outputStream* st,
                                       bool csv_format, const char *columns) {
   ResourceMark rm;
   KlassSizeStats sz, sz_sum;
   int i;
   julong *col_table = (julong*)(&sz);
   julong *colsum_table = (julong*)(&sz_sum);
   int width_table[KlassSizeStats::_num_columns];
   bool selected[KlassSizeStats::_num_columns];
   _selected_columns = columns;
   memset(&sz_sum, 0, sizeof(sz_sum));
   for (int c=0; c<KlassSizeStats::_num_columns; c++) {
     selected[c] = is_selected(name_table[c]);
   }
   for(i=0; i < elements()->length(); i++) {
     elements()->at(i)->set_index(i+1);
   }
   for (int pass=1; pass<=2; pass++) {
     if (pass == 2) {
       print_title(st, csv_format, selected, width_table, name_table);
     }
     for(i=0; i < elements()->length(); i++) {
       KlassInfoEntry* e = (KlassInfoEntry*)elements()->at(i);
       const Klass* k = e->klass();
       memset(&sz, 0, sizeof(sz));
       sz._inst_count = e->count();
       sz._inst_bytes = HeapWordSize * e->words();
       k->collect_statistics(&sz);
       sz._total_bytes = sz._ro_bytes + sz._rw_bytes;
       if (pass == 1) {
         for (int c=0; c<KlassSizeStats::_num_columns; c++) {
           colsum_table[c] += col_table[c];
         }
       } else {
         int super_index = -1;
         if (k->oop_is_instance()) {
           Klass* super = ((InstanceKlass*)k)->java_super();
           if (super) {
             KlassInfoEntry* super_e = _cit->lookup(super);
             if (super_e) {
               super_index = super_e->index();
             }
           }
         }
         if (csv_format) {
           st->print("%d,%d", e->index(), super_index);
           for (int c=0; c<KlassSizeStats::_num_columns; c++) {
             if (selected[c]) {st->print("," JULONG_FORMAT, col_table[c]);}
           }
           st->print(",%s",e->name());
         } else {
           st->print("%5d %5d", e->index(), super_index);
           for (int c=0; c<KlassSizeStats::_num_columns; c++) {
             if (selected[c]) {print_julong(st, width_table[c], col_table[c]);}
           }
           st->print(" %s", e->name());
         }
         if (is_selected("ClassLoader")) {
           ClassLoaderData* loader_data = k->class_loader_data();
           st->print(",");
           loader_data->print_value_on(st);
         }
         st->cr();
       }
     }
     if (pass == 1) {
       for (int c=0; c<KlassSizeStats::_num_columns; c++) {
         width_table[c] = col_width(colsum_table[c], name_table[c]);
       }
     }
   }
   sz_sum._inst_size = 0;
   if (csv_format) {
     st->print(",");
     for (int c=0; c<KlassSizeStats::_num_columns; c++) {
       if (selected[c]) {st->print("," JULONG_FORMAT, colsum_table[c]);}
     }
   } else {
     st->print("           ");
     for (int c=0; c<KlassSizeStats::_num_columns; c++) {
       if (selected[c]) {print_julong(st, width_table[c], colsum_table[c]);}
     }
     st->print(" Total");
     if (sz_sum._total_bytes > 0) {
       st->cr();
       st->print("           ");
       for (int c=0; c<KlassSizeStats::_num_columns; c++) {
         if (selected[c]) {
           switch (c) {
           case KlassSizeStats::_index_inst_size:
           case KlassSizeStats::_index_inst_count:
           case KlassSizeStats::_index_method_count:
             st->print(str_fmt(width_table[c]), "-");
             break;
           default:
             {
               double perc = (double)(100) * (double)(colsum_table[c]) / (double)sz_sum._total_bytes;
               st->print(perc_fmt(width_table[c]), perc);
             }
           }
         }
       }
     }
   }
   st->cr();
   if (!csv_format) {
     print_title(st, csv_format, selected, width_table, name_table);
   }
 }
 julong KlassInfoHisto::annotations_bytes(Array<AnnotationArray*>* p) const {
   julong bytes = 0;
   if (p != NULL) {
     for (int i = 0; i < p->length(); i++) {
       bytes += count_bytes_array(p->at(i));
     }
     bytes += count_bytes_array(p);
   }
   return bytes;
 }
 void KlassInfoHisto::print_histo_on(outputStream* st, bool print_stats,
                                     bool csv_format, const char *columns) {
   if (print_stats) {
     print_class_stats(st, csv_format, columns);
   } else {
     st->print_cr("%s",title());
     print_elements(st);
   }
 }
 class HistoClosure : public KlassInfoClosure {
  private:
   KlassInfoHisto* _cih;
  public:
   HistoClosure(KlassInfoHisto* cih) : _cih(cih) {}
   void do_cinfo(KlassInfoEntry* cie) {
     _cih->add(cie);
   }
 };
 class RecordInstanceClosure : public ObjectClosure {
  private:
   KlassInfoTable* _cit;
   size_t _missed_count;
   BoolObjectClosure* _filter;
  public:
   RecordInstanceClosure(KlassInfoTable* cit, BoolObjectClosure* filter) :
     _cit(cit), _missed_count(0), _filter(filter) {}
   void do_object(oop obj) {
     if (should_visit(obj)) {
       if (!_cit->record_instance(obj)) {
         _missed_count++;
       }
     }
   }
   size_t missed_count() { return _missed_count; }
  private:
   bool should_visit(oop obj) {
     return _filter == NULL || _filter->do_object_b(obj);
   }
 };
 size_t HeapInspection::populate_table(KlassInfoTable* cit, BoolObjectClosure *filter) {
   ResourceMark rm;
   RecordInstanceClosure ric(cit, filter);
   Universe::heap()->object_iterate(&ric);
   return ric.missed_count();
 }
 void HeapInspection::heap_inspection(outputStream* st) {
   ResourceMark rm;
   if (_print_help) {
     for (int c=0; c<KlassSizeStats::_num_columns; c++) {
       st->print("%s:\n\t", name_table[c]);
       const int max_col = 60;
       int col = 0;
       for (const char *p = help_table[c]; *p; p++,col++) {
         if (col >= max_col && *p == ' ') {
           st->print("\n\t");
           col = 0;
         } else {
           st->print("%c", *p);
         }
       }
       st->print_cr(".\n");
     }
     return;
   }
   KlassInfoTable cit(_print_class_stats);
   if (!cit.allocation_failed()) {
     size_t missed_count = populate_table(&cit);
     if (missed_count != 0) {
       st->print_cr("WARNING: Ran out of C-heap; undercounted " SIZE_FORMAT
                    " total instances in data below",
                    missed_count);
     }
     // Sort and print klass instance info
     const char *title = "\n"
               " num     #instances         #bytes  class name\n"
               "----------------------------------------------";
     KlassInfoHisto histo(&cit, title);
     HistoClosure hc(&histo);
     cit.iterate(&hc);
     histo.sort();
     histo.print_histo_on(st, _print_class_stats, _csv_format, _columns);
   } else {
     st->print_cr("WARNING: Ran out of C-heap; histogram not generated");
   }
   st->flush();
 }
 class FindInstanceClosure : public ObjectClosure {
  private:
   Klass* _klass;
   GrowableArray<oop>* _result;
  public:
   FindInstanceClosure(Klass* k, GrowableArray<oop>* result) : _klass(k), _result(result) {};
   void do_object(oop obj) {
     if (obj->is_a(_klass)) {
       _result->append(obj);
     }
   }
 };
 void HeapInspection::find_instances_at_safepoint(Klass* k, GrowableArray<oop>* result) {
   assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
   assert(Heap_lock->is_locked(), "should have the Heap_lock");
   // Ensure that the heap is parsable
   Universe::heap()->ensure_parsability(false);  // no need to retire TALBs
   // Iterate over objects in the heap
   FindInstanceClosure fic(k, result);
   // If this operation encounters a bad object when using CMS,
   // consider using safe_object_iterate() which avoids metadata
   // objects that may contain bad references.
   Universe::heap()->object_iterate(&fic);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/memory/heapInspection.cpp@2c022e432e10 (annotated)

src/share/vm/memory/heapInspection.cpp