jdk-sandbox: comparison src/hotspot/share/gc/g1/heapRegionRemSet.hpp

equal deleted inserted replaced

-:d58442b8abc1
+:3e31a8beaae4
 #define SHARE_GC_G1_HEAPREGIONREMSET_HPP
 #include "gc/g1/g1CodeCacheRemSet.hpp"
 #include "gc/g1/g1FromCardCache.hpp"
 #include "gc/g1/sparsePRT.hpp"
+#include "utilities/bitMap.hpp"
 // Remembered set for a heap region.  Represent a set of "cards" that
 // contain pointers into the owner heap region.  Cards are defined somewhat
 // abstractly, in terms of what the "BlockOffsetTable" in use can parse.
 class G1CollectedHeap;
 class G1BlockOffsetTable;
 class G1CardLiveData;
 class HeapRegion;
-class HeapRegionRemSetIterator;
 class PerRegionTable;
 class SparsePRT;
 class nmethod;
 // The "_coarse_map" is a bitmap with one bit for each region, where set
 //      it's _coarse_map bit is set, so the that we were attempting to add
 //      is represented.  If a deleted PRT is re-used, a thread adding a bit,
 //      thinking the PRT is for a different region, does no harm.
 class OtherRegionsTable {
-friend class HeapRegionRemSetIterator;
 G1CollectedHeap* _g1h;
 Mutex*           _m;
 // These are protected by "_m".
 CHeapBitMap _coarse_map;
 public:
 // Create a new remembered set. The given mutex is used to ensure consistency.
 OtherRegionsTable(Mutex* m);
+template <class Closure>
+void iterate(Closure& v);
 // Returns the card index of the given within_region pointer relative to the bottom
 // of the given heap region.
 static CardIdx_t card_within_region(OopOrNarrowOopStar within_region, HeapRegion* hr);
 // Adds the reference from "from to this remembered set.
 void add_reference(OopOrNarrowOopStar from, uint tid);
 // Clear the entire contents of this remembered set.
 void clear();
 };
+class PerRegionTable: public CHeapObj<mtGC> {
+friend class OtherRegionsTable;
+HeapRegion*     _hr;
+CHeapBitMap     _bm;
+jint            _occupied;
+// next pointer for free/allocated 'all' list
+PerRegionTable* _next;
+// prev pointer for the allocated 'all' list
+PerRegionTable* _prev;
+// next pointer in collision list
+PerRegionTable * _collision_list_next;
+// Global free list of PRTs
+static PerRegionTable* volatile _free_list;
+protected:
+PerRegionTable(HeapRegion* hr) :
+_hr(hr),
+_bm(HeapRegion::CardsPerRegion, mtGC),
+_occupied(0),
+_next(NULL), _prev(NULL),
+_collision_list_next(NULL)
+{}
+inline void add_card_work(CardIdx_t from_card, bool par);
+inline void add_reference_work(OopOrNarrowOopStar from, bool par);
+public:
+// We need access in order to union things into the base table.
+BitMap* bm() { return &_bm; }
+HeapRegion* hr() const { return OrderAccess::load_acquire(&_hr); }
+jint occupied() const {
+// Overkill, but if we ever need it...
+// guarantee(_occupied == _bm.count_one_bits(), "Check");
+return _occupied;
+}
+void init(HeapRegion* hr, bool clear_links_to_all_list);
+inline void add_reference(OopOrNarrowOopStar from);
+inline void seq_add_reference(OopOrNarrowOopStar from);
+inline void add_card(CardIdx_t from_card_index);
+void seq_add_card(CardIdx_t from_card_index);
+// (Destructively) union the bitmap of the current table into the given
+// bitmap (which is assumed to be of the same size.)
+void union_bitmap_into(BitMap* bm) {
+bm->set_union(_bm);
+}
+// Mem size in bytes.
+size_t mem_size() const {
+return sizeof(PerRegionTable) + _bm.size_in_words() * HeapWordSize;
+}
+// Requires "from" to be in "hr()".
+bool contains_reference(OopOrNarrowOopStar from) const {
+assert(hr()->is_in_reserved(from), "Precondition.");
+size_t card_ind = pointer_delta(from, hr()->bottom(),
+G1CardTable::card_size);
+return _bm.at(card_ind);
+}
+// Bulk-free the PRTs from prt to last, assumes that they are
+// linked together using their _next field.
+static void bulk_free(PerRegionTable* prt, PerRegionTable* last) {
+while (true) {
+PerRegionTable* fl = _free_list;
+last->set_next(fl);
+PerRegionTable* res = Atomic::cmpxchg(prt, &_free_list, fl);
+if (res == fl) {
+return;
+}
+}
+ShouldNotReachHere();
+}
+static void free(PerRegionTable* prt) {
+bulk_free(prt, prt);
+}
+// Returns an initialized PerRegionTable instance.
+static PerRegionTable* alloc(HeapRegion* hr);
+PerRegionTable* next() const { return _next; }
+void set_next(PerRegionTable* next) { _next = next; }
+PerRegionTable* prev() const { return _prev; }
+void set_prev(PerRegionTable* prev) { _prev = prev; }
+// Accessor and Modification routines for the pointer for the
+// singly linked collision list that links the PRTs within the
+// OtherRegionsTable::_fine_grain_regions hash table.
+//
+// It might be useful to also make the collision list doubly linked
+// to avoid iteration over the collisions list during scrubbing/deletion.
+// OTOH there might not be many collisions.
+PerRegionTable* collision_list_next() const {
+return _collision_list_next;
+}
+void set_collision_list_next(PerRegionTable* next) {
+_collision_list_next = next;
+}
+PerRegionTable** collision_list_next_addr() {
+return &_collision_list_next;
+}
+static size_t fl_mem_size() {
+PerRegionTable* cur = _free_list;
+size_t res = 0;
+while (cur != NULL) {
+res += cur->mem_size();
+cur = cur->next();
+}
+return res;
+}
+static void test_fl_mem_size();
+};
 class HeapRegionRemSet : public CHeapObj<mtGC> {
 friend class VMStructs;
-friend class HeapRegionRemSetIterator;
 private:
 G1BlockOffsetTable* _bot;
 // A set of code blobs (nmethods) whose code contains pointers into
 HeapRegionRemSet(G1BlockOffsetTable* bot, HeapRegion* hr);
 // Setup sparse and fine-grain tables sizes.
 static void setup_remset_size();
-bool cardset_is_empty() const {
-return _other_regions.is_empty();
-}
 bool is_empty() const {
-return (strong_code_roots_list_length() == 0) && cardset_is_empty();
+return (strong_code_roots_list_length() == 0) && _other_regions.is_empty();
 }
 bool occupancy_less_or_equal_than(size_t occ) const {
 return (strong_code_roots_list_length() == 0) && _other_regions.occupancy_less_or_equal_than(occ);
 }
+// For each PRT in the card (remembered) set call one of the following methods
+// of the given closure:
+//
+// set_full_region_dirty(uint region_idx) - pass the region index for coarse PRTs
+// set_bitmap_dirty(uint region_idx, BitMap* bitmap) - pass the region index and bitmap for fine PRTs
+// set_cards_dirty(uint region_idx, elem_t* cards, uint num_cards) - pass region index and cards for sparse PRTs
+template <class Closure>
+inline void iterate_prts(Closure& cl);
 size_t occupied() {
 MutexLocker x(&_m, Mutex::_no_safepoint_check_flag);
 return occupied_locked();
 }
 static void test();
 #endif
 };
-class HeapRegionRemSetIterator : public StackObj {
-private:
-// The region RSet over which we are iterating.
-HeapRegionRemSet* _hrrs;
-// Local caching of HRRS fields.
-const BitMap*             _coarse_map;
-G1BlockOffsetTable*       _bot;
-G1CollectedHeap*          _g1h;
-// The number of cards yielded since initialization.
-size_t _n_yielded_fine;
-size_t _n_yielded_coarse;
-size_t _n_yielded_sparse;
-// Indicates what granularity of table that we are currently iterating over.
-// We start iterating over the sparse table, progress to the fine grain
-// table, and then finish with the coarse table.
-enum IterState {
-Sparse,
-Fine,
-Coarse
-};
-IterState _is;
-// For both Coarse and Fine remembered set iteration this contains the
-// first card number of the heap region we currently iterate over.
-size_t _cur_region_card_offset;
-// Current region index for the Coarse remembered set iteration.
-int    _coarse_cur_region_index;
-size_t _coarse_cur_region_cur_card;
-bool coarse_has_next(size_t& card_index);
-// The PRT we are currently iterating over.
-PerRegionTable* _fine_cur_prt;
-// Card offset within the current PRT.
-size_t _cur_card_in_prt;
-// Update internal variables when switching to the given PRT.
-void switch_to_prt(PerRegionTable* prt);
-bool fine_has_next();
-bool fine_has_next(size_t& card_index);
-// The Sparse remembered set iterator.
-SparsePRTIter _sparse_iter;
-public:
-HeapRegionRemSetIterator(HeapRegionRemSet* hrrs);
-// If there remains one or more cards to be yielded, returns true and
-// sets "card_index" to one of those cards (which is then considered
-// yielded.)   Otherwise, returns false (and leaves "card_index"
-// undefined.)
-bool has_next(size_t& card_index);
-size_t n_yielded_fine() { return _n_yielded_fine; }
-size_t n_yielded_coarse() { return _n_yielded_coarse; }
-size_t n_yielded_sparse() { return _n_yielded_sparse; }
-size_t n_yielded() {
-return n_yielded_fine() + n_yielded_coarse() + n_yielded_sparse();
-}
-};
 #endif // SHARE_GC_G1_HEAPREGIONREMSET_HPP

changeset 55510	3e31a8beaae4
parent 55148	0dab93cb3b0c
child 58552	906a9dd5d8e8