--- a/hotspot/src/share/vm/gc/g1/concurrentMark.inline.hpp Wed Feb 10 10:26:41 2016 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,377 +0,0 @@
-/*
- * Copyright (c) 2001, 2015, 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.
- *
- */
-
-#ifndef SHARE_VM_GC_G1_CONCURRENTMARK_INLINE_HPP
-#define SHARE_VM_GC_G1_CONCURRENTMARK_INLINE_HPP
-
-#include "gc/g1/concurrentMark.hpp"
-#include "gc/g1/g1CollectedHeap.inline.hpp"
-#include "gc/shared/taskqueue.inline.hpp"
-
-// Utility routine to set an exclusive range of cards on the given
-// card liveness bitmap
-inline void ConcurrentMark::set_card_bitmap_range(BitMap* card_bm,
- BitMap::idx_t start_idx,
- BitMap::idx_t end_idx,
- bool is_par) {
-
- // Set the exclusive bit range [start_idx, end_idx).
- assert((end_idx - start_idx) > 0, "at least one card");
- assert(end_idx <= card_bm->size(), "sanity");
-
- // Silently clip the end index
- end_idx = MIN2(end_idx, card_bm->size());
-
- // For small ranges use a simple loop; otherwise use set_range or
- // use par_at_put_range (if parallel). The range is made up of the
- // cards that are spanned by an object/mem region so 8 cards will
- // allow up to object sizes up to 4K to be handled using the loop.
- if ((end_idx - start_idx) <= 8) {
- for (BitMap::idx_t i = start_idx; i < end_idx; i += 1) {
- if (is_par) {
- card_bm->par_set_bit(i);
- } else {
- card_bm->set_bit(i);
- }
- }
- } else {
- // Note BitMap::par_at_put_range() and BitMap::set_range() are exclusive.
- if (is_par) {
- card_bm->par_at_put_range(start_idx, end_idx, true);
- } else {
- card_bm->set_range(start_idx, end_idx);
- }
- }
-}
-
-// Returns the index in the liveness accounting card bitmap
-// for the given address
-inline BitMap::idx_t ConcurrentMark::card_bitmap_index_for(HeapWord* addr) {
- // Below, the term "card num" means the result of shifting an address
- // by the card shift -- address 0 corresponds to card number 0. One
- // must subtract the card num of the bottom of the heap to obtain a
- // card table index.
- intptr_t card_num = intptr_t(uintptr_t(addr) >> CardTableModRefBS::card_shift);
- return card_num - heap_bottom_card_num();
-}
-
-// Counts the given memory region in the given task/worker
-// counting data structures.
-inline void ConcurrentMark::count_region(MemRegion mr, HeapRegion* hr,
- size_t* marked_bytes_array,
- BitMap* task_card_bm) {
- G1CollectedHeap* g1h = _g1h;
- CardTableModRefBS* ct_bs = g1h->g1_barrier_set();
-
- HeapWord* start = mr.start();
- HeapWord* end = mr.end();
- size_t region_size_bytes = mr.byte_size();
- uint index = hr->hrm_index();
-
- assert(hr == g1h->heap_region_containing(start), "sanity");
- assert(marked_bytes_array != NULL, "pre-condition");
- assert(task_card_bm != NULL, "pre-condition");
-
- // Add to the task local marked bytes for this region.
- marked_bytes_array[index] += region_size_bytes;
-
- BitMap::idx_t start_idx = card_bitmap_index_for(start);
- BitMap::idx_t end_idx = card_bitmap_index_for(end);
-
- // Note: if we're looking at the last region in heap - end
- // could be actually just beyond the end of the heap; end_idx
- // will then correspond to a (non-existent) card that is also
- // just beyond the heap.
- if (g1h->is_in_g1_reserved(end) && !ct_bs->is_card_aligned(end)) {
- // end of region is not card aligned - increment to cover
- // all the cards spanned by the region.
- end_idx += 1;
- }
- // The card bitmap is task/worker specific => no need to use
- // the 'par' BitMap routines.
- // Set bits in the exclusive bit range [start_idx, end_idx).
- set_card_bitmap_range(task_card_bm, start_idx, end_idx, false /* is_par */);
-}
-
-// Counts the given object in the given task/worker counting data structures.
-inline void ConcurrentMark::count_object(oop obj,
- HeapRegion* hr,
- size_t* marked_bytes_array,
- BitMap* task_card_bm,
- size_t word_size) {
- assert(!hr->is_continues_humongous(), "Cannot enter count_object with continues humongous");
- if (!hr->is_starts_humongous()) {
- MemRegion mr((HeapWord*)obj, word_size);
- count_region(mr, hr, marked_bytes_array, task_card_bm);
- } else {
- do {
- MemRegion mr(hr->bottom(), hr->top());
- count_region(mr, hr, marked_bytes_array, task_card_bm);
- hr = _g1h->next_region_in_humongous(hr);
- } while (hr != NULL);
- }
-}
-
-// Attempts to mark the given object and, if successful, counts
-// the object in the given task/worker counting structures.
-inline bool ConcurrentMark::par_mark_and_count(oop obj,
- HeapRegion* hr,
- size_t* marked_bytes_array,
- BitMap* task_card_bm) {
- if (_nextMarkBitMap->parMark((HeapWord*)obj)) {
- // Update the task specific count data for the object.
- count_object(obj, hr, marked_bytes_array, task_card_bm, obj->size());
- return true;
- }
- return false;
-}
-
-// Attempts to mark the given object and, if successful, counts
-// the object in the task/worker counting structures for the
-// given worker id.
-inline bool ConcurrentMark::par_mark_and_count(oop obj,
- size_t word_size,
- HeapRegion* hr,
- uint worker_id) {
- if (_nextMarkBitMap->parMark((HeapWord*)obj)) {
- size_t* marked_bytes_array = count_marked_bytes_array_for(worker_id);
- BitMap* task_card_bm = count_card_bitmap_for(worker_id);
- count_object(obj, hr, marked_bytes_array, task_card_bm, word_size);
- return true;
- }
- return false;
-}
-
-inline bool CMBitMapRO::iterate(BitMapClosure* cl, MemRegion mr) {
- HeapWord* start_addr = MAX2(startWord(), mr.start());
- HeapWord* end_addr = MIN2(endWord(), mr.end());
-
- if (end_addr > start_addr) {
- // Right-open interval [start-offset, end-offset).
- BitMap::idx_t start_offset = heapWordToOffset(start_addr);
- BitMap::idx_t end_offset = heapWordToOffset(end_addr);
-
- start_offset = _bm.get_next_one_offset(start_offset, end_offset);
- while (start_offset < end_offset) {
- if (!cl->do_bit(start_offset)) {
- return false;
- }
- HeapWord* next_addr = MIN2(nextObject(offsetToHeapWord(start_offset)), end_addr);
- BitMap::idx_t next_offset = heapWordToOffset(next_addr);
- start_offset = _bm.get_next_one_offset(next_offset, end_offset);
- }
- }
- return true;
-}
-
-#define check_mark(addr) \
- assert(_bmStartWord <= (addr) && (addr) < (_bmStartWord + _bmWordSize), \
- "outside underlying space?"); \
- assert(G1CollectedHeap::heap()->is_in_exact(addr), \
- "Trying to access not available bitmap " PTR_FORMAT \
- " corresponding to " PTR_FORMAT " (%u)", \
- p2i(this), p2i(addr), G1CollectedHeap::heap()->addr_to_region(addr));
-
-inline void CMBitMap::mark(HeapWord* addr) {
- check_mark(addr);
- _bm.set_bit(heapWordToOffset(addr));
-}
-
-inline void CMBitMap::clear(HeapWord* addr) {
- check_mark(addr);
- _bm.clear_bit(heapWordToOffset(addr));
-}
-
-inline bool CMBitMap::parMark(HeapWord* addr) {
- check_mark(addr);
- return _bm.par_set_bit(heapWordToOffset(addr));
-}
-
-#undef check_mark
-
-template<typename Fn>
-inline void CMMarkStack::iterate(Fn fn) {
- assert(_saved_index == _index, "saved index: %d index: %d", _saved_index, _index);
- for (int i = 0; i < _index; ++i) {
- fn(_base[i]);
- }
-}
-
-// It scans an object and visits its children.
-inline void CMTask::scan_object(oop obj) { process_grey_object<true>(obj); }
-
-inline void CMTask::push(oop obj) {
- HeapWord* objAddr = (HeapWord*) obj;
- assert(_g1h->is_in_g1_reserved(objAddr), "invariant");
- assert(!_g1h->is_on_master_free_list(
- _g1h->heap_region_containing((HeapWord*) objAddr)), "invariant");
- assert(!_g1h->is_obj_ill(obj), "invariant");
- assert(_nextMarkBitMap->isMarked(objAddr), "invariant");
-
- if (!_task_queue->push(obj)) {
- // The local task queue looks full. We need to push some entries
- // to the global stack.
- move_entries_to_global_stack();
-
- // this should succeed since, even if we overflow the global
- // stack, we should have definitely removed some entries from the
- // local queue. So, there must be space on it.
- bool success = _task_queue->push(obj);
- assert(success, "invariant");
- }
-}
-
-inline bool CMTask::is_below_finger(oop obj, HeapWord* global_finger) const {
- // If obj is above the global finger, then the mark bitmap scan
- // will find it later, and no push is needed. Similarly, if we have
- // a current region and obj is between the local finger and the
- // end of the current region, then no push is needed. The tradeoff
- // of checking both vs only checking the global finger is that the
- // local check will be more accurate and so result in fewer pushes,
- // but may also be a little slower.
- HeapWord* objAddr = (HeapWord*)obj;
- if (_finger != NULL) {
- // We have a current region.
-
- // Finger and region values are all NULL or all non-NULL. We
- // use _finger to check since we immediately use its value.
- assert(_curr_region != NULL, "invariant");
- assert(_region_limit != NULL, "invariant");
- assert(_region_limit <= global_finger, "invariant");
-
- // True if obj is less than the local finger, or is between
- // the region limit and the global finger.
- if (objAddr < _finger) {
- return true;
- } else if (objAddr < _region_limit) {
- return false;
- } // Else check global finger.
- }
- // Check global finger.
- return objAddr < global_finger;
-}
-
-template<bool scan>
-inline void CMTask::process_grey_object(oop obj) {
- assert(scan || obj->is_typeArray(), "Skipping scan of grey non-typeArray");
- assert(_nextMarkBitMap->isMarked((HeapWord*) obj), "invariant");
-
- size_t obj_size = obj->size();
- _words_scanned += obj_size;
-
- if (scan) {
- obj->oop_iterate(_cm_oop_closure);
- }
- check_limits();
-}
-
-
-
-inline void CMTask::make_reference_grey(oop obj, HeapRegion* hr) {
- if (_cm->par_mark_and_count(obj, hr, _marked_bytes_array, _card_bm)) {
- // No OrderAccess:store_load() is needed. It is implicit in the
- // CAS done in CMBitMap::parMark() call in the routine above.
- HeapWord* global_finger = _cm->finger();
-
- // We only need to push a newly grey object on the mark
- // stack if it is in a section of memory the mark bitmap
- // scan has already examined. Mark bitmap scanning
- // maintains progress "fingers" for determining that.
- //
- // Notice that the global finger might be moving forward
- // concurrently. This is not a problem. In the worst case, we
- // mark the object while it is above the global finger and, by
- // the time we read the global finger, it has moved forward
- // past this object. In this case, the object will probably
- // be visited when a task is scanning the region and will also
- // be pushed on the stack. So, some duplicate work, but no
- // correctness problems.
- if (is_below_finger(obj, global_finger)) {
- if (obj->is_typeArray()) {
- // Immediately process arrays of primitive types, rather
- // than pushing on the mark stack. This keeps us from
- // adding humongous objects to the mark stack that might
- // be reclaimed before the entry is processed - see
- // selection of candidates for eager reclaim of humongous
- // objects. The cost of the additional type test is
- // mitigated by avoiding a trip through the mark stack,
- // by only doing a bookkeeping update and avoiding the
- // actual scan of the object - a typeArray contains no
- // references, and the metadata is built-in.
- process_grey_object<false>(obj);
- } else {
- push(obj);
- }
- }
- }
-}
-
-inline void CMTask::deal_with_reference(oop obj) {
- increment_refs_reached();
-
- HeapWord* objAddr = (HeapWord*) obj;
- assert(obj->is_oop_or_null(true /* ignore mark word */), "Expected an oop or NULL at " PTR_FORMAT, p2i(obj));
- if (_g1h->is_in_g1_reserved(objAddr)) {
- assert(obj != NULL, "null check is implicit");
- if (!_nextMarkBitMap->isMarked(objAddr)) {
- // Only get the containing region if the object is not marked on the
- // bitmap (otherwise, it's a waste of time since we won't do
- // anything with it).
- HeapRegion* hr = _g1h->heap_region_containing(obj);
- if (!hr->obj_allocated_since_next_marking(obj)) {
- make_reference_grey(obj, hr);
- }
- }
- }
-}
-
-inline void ConcurrentMark::markPrev(oop p) {
- assert(!_prevMarkBitMap->isMarked((HeapWord*) p), "sanity");
- // Note we are overriding the read-only view of the prev map here, via
- // the cast.
- ((CMBitMap*)_prevMarkBitMap)->mark((HeapWord*) p);
-}
-
-inline void ConcurrentMark::grayRoot(oop obj, size_t word_size,
- uint worker_id, HeapRegion* hr) {
- assert(obj != NULL, "pre-condition");
- HeapWord* addr = (HeapWord*) obj;
- if (hr == NULL) {
- hr = _g1h->heap_region_containing(addr);
- } else {
- assert(hr->is_in(addr), "pre-condition");
- }
- assert(hr != NULL, "sanity");
- // Given that we're looking for a region that contains an object
- // header it's impossible to get back a HC region.
- assert(!hr->is_continues_humongous(), "sanity");
-
- if (addr < hr->next_top_at_mark_start()) {
- if (!_nextMarkBitMap->isMarked(addr)) {
- par_mark_and_count(obj, word_size, hr, worker_id);
- }
- }
-}
-
-#endif // SHARE_VM_GC_G1_CONCURRENTMARK_INLINE_HPP