--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/parallel/parMarkBitMap.cpp Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,219 @@
+/*
+ * Copyright (c) 2005, 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/parallel/parMarkBitMap.hpp"
+#include "gc/parallel/psParallelCompact.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/atomic.inline.hpp"
+#include "runtime/os.hpp"
+#include "services/memTracker.hpp"
+#include "utilities/bitMap.inline.hpp"
+
+bool
+ParMarkBitMap::initialize(MemRegion covered_region)
+{
+ const idx_t bits = bits_required(covered_region);
+ // The bits will be divided evenly between two bitmaps; each of them should be
+ // an integral number of words.
+ assert(bits % (BitsPerWord * 2) == 0, "region size unaligned");
+
+ const size_t words = bits / BitsPerWord;
+ const size_t raw_bytes = words * sizeof(idx_t);
+ const size_t page_sz = os::page_size_for_region_aligned(raw_bytes, 10);
+ const size_t granularity = os::vm_allocation_granularity();
+ _reserved_byte_size = align_size_up(raw_bytes, MAX2(page_sz, granularity));
+
+ const size_t rs_align = page_sz == (size_t) os::vm_page_size() ? 0 :
+ MAX2(page_sz, granularity);
+ ReservedSpace rs(_reserved_byte_size, rs_align, rs_align > 0);
+ os::trace_page_sizes("par bitmap", raw_bytes, raw_bytes, page_sz,
+ rs.base(), rs.size());
+
+ MemTracker::record_virtual_memory_type((address)rs.base(), mtGC);
+
+ _virtual_space = new PSVirtualSpace(rs, page_sz);
+ if (_virtual_space != NULL && _virtual_space->expand_by(_reserved_byte_size)) {
+ _region_start = covered_region.start();
+ _region_size = covered_region.word_size();
+ BitMap::bm_word_t* map = (BitMap::bm_word_t*)_virtual_space->reserved_low_addr();
+ _beg_bits.set_map(map);
+ _beg_bits.set_size(bits / 2);
+ _end_bits.set_map(map + words / 2);
+ _end_bits.set_size(bits / 2);
+ return true;
+ }
+
+ _region_start = 0;
+ _region_size = 0;
+ if (_virtual_space != NULL) {
+ delete _virtual_space;
+ _virtual_space = NULL;
+ // Release memory reserved in the space.
+ rs.release();
+ }
+ return false;
+}
+
+#ifdef ASSERT
+extern size_t mark_bitmap_count;
+extern size_t mark_bitmap_size;
+#endif // #ifdef ASSERT
+
+bool
+ParMarkBitMap::mark_obj(HeapWord* addr, size_t size)
+{
+ const idx_t beg_bit = addr_to_bit(addr);
+ if (_beg_bits.par_set_bit(beg_bit)) {
+ const idx_t end_bit = addr_to_bit(addr + size - 1);
+ bool end_bit_ok = _end_bits.par_set_bit(end_bit);
+ assert(end_bit_ok, "concurrency problem");
+ DEBUG_ONLY(Atomic::inc_ptr(&mark_bitmap_count));
+ DEBUG_ONLY(Atomic::add_ptr(size, &mark_bitmap_size));
+ return true;
+ }
+ return false;
+}
+
+size_t ParMarkBitMap::live_words_in_range(HeapWord* beg_addr, oop end_obj) const
+{
+ assert(beg_addr <= (HeapWord*)end_obj, "bad range");
+ assert(is_marked(end_obj), "end_obj must be live");
+
+ idx_t live_bits = 0;
+
+ // The bitmap routines require the right boundary to be word-aligned.
+ const idx_t end_bit = addr_to_bit((HeapWord*)end_obj);
+ const idx_t range_end = BitMap::word_align_up(end_bit);
+
+ idx_t beg_bit = find_obj_beg(addr_to_bit(beg_addr), range_end);
+ while (beg_bit < end_bit) {
+ idx_t tmp_end = find_obj_end(beg_bit, range_end);
+ assert(tmp_end < end_bit, "missing end bit");
+ live_bits += tmp_end - beg_bit + 1;
+ beg_bit = find_obj_beg(tmp_end + 1, range_end);
+ }
+ return bits_to_words(live_bits);
+}
+
+ParMarkBitMap::IterationStatus
+ParMarkBitMap::iterate(ParMarkBitMapClosure* live_closure,
+ idx_t range_beg, idx_t range_end) const
+{
+ DEBUG_ONLY(verify_bit(range_beg);)
+ DEBUG_ONLY(verify_bit(range_end);)
+ assert(range_beg <= range_end, "live range invalid");
+
+ // The bitmap routines require the right boundary to be word-aligned.
+ const idx_t search_end = BitMap::word_align_up(range_end);
+
+ idx_t cur_beg = find_obj_beg(range_beg, search_end);
+ while (cur_beg < range_end) {
+ const idx_t cur_end = find_obj_end(cur_beg, search_end);
+ if (cur_end >= range_end) {
+ // The obj ends outside the range.
+ live_closure->set_source(bit_to_addr(cur_beg));
+ return incomplete;
+ }
+
+ const size_t size = obj_size(cur_beg, cur_end);
+ IterationStatus status = live_closure->do_addr(bit_to_addr(cur_beg), size);
+ if (status != incomplete) {
+ assert(status == would_overflow || status == full, "sanity");
+ return status;
+ }
+
+ // Successfully processed the object; look for the next object.
+ cur_beg = find_obj_beg(cur_end + 1, search_end);
+ }
+
+ live_closure->set_source(bit_to_addr(range_end));
+ return complete;
+}
+
+ParMarkBitMap::IterationStatus
+ParMarkBitMap::iterate(ParMarkBitMapClosure* live_closure,
+ ParMarkBitMapClosure* dead_closure,
+ idx_t range_beg, idx_t range_end,
+ idx_t dead_range_end) const
+{
+ DEBUG_ONLY(verify_bit(range_beg);)
+ DEBUG_ONLY(verify_bit(range_end);)
+ DEBUG_ONLY(verify_bit(dead_range_end);)
+ assert(range_beg <= range_end, "live range invalid");
+ assert(range_end <= dead_range_end, "dead range invalid");
+
+ // The bitmap routines require the right boundary to be word-aligned.
+ const idx_t live_search_end = BitMap::word_align_up(range_end);
+ const idx_t dead_search_end = BitMap::word_align_up(dead_range_end);
+
+ idx_t cur_beg = range_beg;
+ if (range_beg < range_end && is_unmarked(range_beg)) {
+ // The range starts with dead space. Look for the next object, then fill.
+ cur_beg = find_obj_beg(range_beg + 1, dead_search_end);
+ const idx_t dead_space_end = MIN2(cur_beg - 1, dead_range_end - 1);
+ const size_t size = obj_size(range_beg, dead_space_end);
+ dead_closure->do_addr(bit_to_addr(range_beg), size);
+ }
+
+ while (cur_beg < range_end) {
+ const idx_t cur_end = find_obj_end(cur_beg, live_search_end);
+ if (cur_end >= range_end) {
+ // The obj ends outside the range.
+ live_closure->set_source(bit_to_addr(cur_beg));
+ return incomplete;
+ }
+
+ const size_t size = obj_size(cur_beg, cur_end);
+ IterationStatus status = live_closure->do_addr(bit_to_addr(cur_beg), size);
+ if (status != incomplete) {
+ assert(status == would_overflow || status == full, "sanity");
+ return status;
+ }
+
+ // Look for the start of the next object.
+ const idx_t dead_space_beg = cur_end + 1;
+ cur_beg = find_obj_beg(dead_space_beg, dead_search_end);
+ if (cur_beg > dead_space_beg) {
+ // Found dead space; compute the size and invoke the dead closure.
+ const idx_t dead_space_end = MIN2(cur_beg - 1, dead_range_end - 1);
+ const size_t size = obj_size(dead_space_beg, dead_space_end);
+ dead_closure->do_addr(bit_to_addr(dead_space_beg), size);
+ }
+ }
+
+ live_closure->set_source(bit_to_addr(range_end));
+ return complete;
+}
+
+#ifdef ASSERT
+void ParMarkBitMap::verify_clear() const
+{
+ const idx_t* const beg = (const idx_t*)_virtual_space->committed_low_addr();
+ const idx_t* const end = (const idx_t*)_virtual_space->committed_high_addr();
+ for (const idx_t* p = beg; p < end; ++p) {
+ assert(*p == 0, "bitmap not clear");
+ }
+}
+#endif // #ifdef ASSERT