jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/heapRegionManager.cpp@c2844108a708 (annotated)

src/share/vm/gc_implementation/g1/heapRegionManager.cpp@c2844108a708 (annotated)

src/share/vm/gc_implementation/g1/heapRegionManager.cpp

Thu, 23 Oct 2014 12:02:08 -0700

author: asaha
date: Thu, 23 Oct 2014 12:02:08 -0700
changeset 7476: c2844108a708
parent 7131: d35872270666
child 7535: 7ae4e26cb1e0
child 7835: e5406a79ae90
permissions: -rw-r--r--

Merge

 /*
  * Copyright (c) 2001, 2014, 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_implementation/g1/heapRegion.hpp"
 #include "gc_implementation/g1/heapRegionManager.inline.hpp"
 #include "gc_implementation/g1/heapRegionSet.inline.hpp"
 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
 #include "gc_implementation/g1/concurrentG1Refine.hpp"
 #include "memory/allocation.hpp"
 void HeapRegionManager::initialize(G1RegionToSpaceMapper* heap_storage,
                                G1RegionToSpaceMapper* prev_bitmap,
                                G1RegionToSpaceMapper* next_bitmap,
                                G1RegionToSpaceMapper* bot,
                                G1RegionToSpaceMapper* cardtable,
                                G1RegionToSpaceMapper* card_counts) {
   _allocated_heapregions_length = 0;
   _heap_mapper = heap_storage;
   _prev_bitmap_mapper = prev_bitmap;
   _next_bitmap_mapper = next_bitmap;
   _bot_mapper = bot;
   _cardtable_mapper = cardtable;
   _card_counts_mapper = card_counts;
   MemRegion reserved = heap_storage->reserved();
   _regions.initialize(reserved.start(), reserved.end(), HeapRegion::GrainBytes);
   _available_map.resize(_regions.length(), false);
   _available_map.clear();
 }
 bool HeapRegionManager::is_available(uint region) const {
   return _available_map.at(region);
 }
 #ifdef ASSERT
 bool HeapRegionManager::is_free(HeapRegion* hr) const {
   return _free_list.contains(hr);
 }
 #endif
 HeapRegion* HeapRegionManager::new_heap_region(uint hrm_index) {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   HeapWord* bottom = g1h->bottom_addr_for_region(hrm_index);
   MemRegion mr(bottom, bottom + HeapRegion::GrainWords);
   assert(reserved().contains(mr), "invariant");
   return g1h->allocator()->new_heap_region(hrm_index, g1h->bot_shared(), mr);
 }
 void HeapRegionManager::commit_regions(uint index, size_t num_regions) {
   guarantee(num_regions > 0, "Must commit more than zero regions");
   guarantee(_num_committed + num_regions <= max_length(), "Cannot commit more than the maximum amount of regions");
   _num_committed += (uint)num_regions;
   _heap_mapper->commit_regions(index, num_regions);
   // Also commit auxiliary data
   _prev_bitmap_mapper->commit_regions(index, num_regions);
   _next_bitmap_mapper->commit_regions(index, num_regions);
   _bot_mapper->commit_regions(index, num_regions);
   _cardtable_mapper->commit_regions(index, num_regions);
   _card_counts_mapper->commit_regions(index, num_regions);
 }
 void HeapRegionManager::uncommit_regions(uint start, size_t num_regions) {
   guarantee(num_regions >= 1, err_msg("Need to specify at least one region to uncommit, tried to uncommit zero regions at %u", start));
   guarantee(_num_committed >= num_regions, "pre-condition");
   // Print before uncommitting.
   if (G1CollectedHeap::heap()->hr_printer()->is_active()) {
     for (uint i = start; i < start + num_regions; i++) {
       HeapRegion* hr = at(i);
       G1CollectedHeap::heap()->hr_printer()->uncommit(hr->bottom(), hr->end());
     }
   }
   _num_committed -= (uint)num_regions;
   _available_map.par_clear_range(start, start + num_regions, BitMap::unknown_range);
   _heap_mapper->uncommit_regions(start, num_regions);
   // Also uncommit auxiliary data
   _prev_bitmap_mapper->uncommit_regions(start, num_regions);
   _next_bitmap_mapper->uncommit_regions(start, num_regions);
   _bot_mapper->uncommit_regions(start, num_regions);
   _cardtable_mapper->uncommit_regions(start, num_regions);
   _card_counts_mapper->uncommit_regions(start, num_regions);
 }
 void HeapRegionManager::make_regions_available(uint start, uint num_regions) {
   guarantee(num_regions > 0, "No point in calling this for zero regions");
   commit_regions(start, num_regions);
   for (uint i = start; i < start + num_regions; i++) {
     if (_regions.get_by_index(i) == NULL) {
       HeapRegion* new_hr = new_heap_region(i);
       _regions.set_by_index(i, new_hr);
       _allocated_heapregions_length = MAX2(_allocated_heapregions_length, i + 1);
     }
   }
   _available_map.par_set_range(start, start + num_regions, BitMap::unknown_range);
   for (uint i = start; i < start + num_regions; i++) {
     assert(is_available(i), err_msg("Just made region %u available but is apparently not.", i));
     HeapRegion* hr = at(i);
     if (G1CollectedHeap::heap()->hr_printer()->is_active()) {
       G1CollectedHeap::heap()->hr_printer()->commit(hr->bottom(), hr->end());
     }
     HeapWord* bottom = G1CollectedHeap::heap()->bottom_addr_for_region(i);
     MemRegion mr(bottom, bottom + HeapRegion::GrainWords);
     hr->initialize(mr);
     insert_into_free_list(at(i));
   }
 }
 uint HeapRegionManager::expand_by(uint num_regions) {
   return expand_at(0, num_regions);
 }
 uint HeapRegionManager::expand_at(uint start, uint num_regions) {
   if (num_regions == 0) {
     return 0;
   }
   uint cur = start;
   uint idx_last_found = 0;
   uint num_last_found = 0;
   uint expanded = 0;
   while (expanded < num_regions &&
          (num_last_found = find_unavailable_from_idx(cur, &idx_last_found)) > 0) {
     uint to_expand = MIN2(num_regions - expanded, num_last_found);
     make_regions_available(idx_last_found, to_expand);
     expanded += to_expand;
     cur = idx_last_found + num_last_found + 1;
   }
   verify_optional();
   return expanded;
 }
 uint HeapRegionManager::find_contiguous(size_t num, bool empty_only) {
   uint found = 0;
   size_t length_found = 0;
   uint cur = 0;
   while (length_found < num && cur < max_length()) {
     HeapRegion* hr = _regions.get_by_index(cur);
     if ((!empty_only && !is_available(cur)) || (is_available(cur) && hr != NULL && hr->is_empty())) {
       // This region is a potential candidate for allocation into.
       length_found++;
     } else {
       // This region is not a candidate. The next region is the next possible one.
       found = cur + 1;
       length_found = 0;
     }
     cur++;
   }
   if (length_found == num) {
     for (uint i = found; i < (found + num); i++) {
       HeapRegion* hr = _regions.get_by_index(i);
       // sanity check
       guarantee((!empty_only && !is_available(i)) || (is_available(i) && hr != NULL && hr->is_empty()),
                 err_msg("Found region sequence starting at " UINT32_FORMAT ", length " SIZE_FORMAT
                         " that is not empty at " UINT32_FORMAT ". Hr is " PTR_FORMAT, found, num, i, p2i(hr)));
     }
     return found;
   } else {
     return G1_NO_HRM_INDEX;
   }
 }
 HeapRegion* HeapRegionManager::next_region_in_heap(const HeapRegion* r) const {
   guarantee(r != NULL, "Start region must be a valid region");
   guarantee(is_available(r->hrm_index()), err_msg("Trying to iterate starting from region %u which is not in the heap", r->hrm_index()));
   for (uint i = r->hrm_index() + 1; i < _allocated_heapregions_length; i++) {
     HeapRegion* hr = _regions.get_by_index(i);
     if (is_available(i)) {
       return hr;
     }
   }
   return NULL;
 }
 void HeapRegionManager::iterate(HeapRegionClosure* blk) const {
   uint len = max_length();
   for (uint i = 0; i < len; i++) {
     if (!is_available(i)) {
       continue;
     }
     guarantee(at(i) != NULL, err_msg("Tried to access region %u that has a NULL HeapRegion*", i));
     bool res = blk->doHeapRegion(at(i));
     if (res) {
       blk->incomplete();
       return;
     }
   }
 }
 uint HeapRegionManager::find_unavailable_from_idx(uint start_idx, uint* res_idx) const {
   guarantee(res_idx != NULL, "checking");
   guarantee(start_idx <= (max_length() + 1), "checking");
   uint num_regions = 0;
   uint cur = start_idx;
   while (cur < max_length() && is_available(cur)) {
     cur++;
   }
   if (cur == max_length()) {
     return num_regions;
   }
   *res_idx = cur;
   while (cur < max_length() && !is_available(cur)) {
     cur++;
   }
   num_regions = cur - *res_idx;
 #ifdef ASSERT
   for (uint i = *res_idx; i < (*res_idx + num_regions); i++) {
     assert(!is_available(i), "just checking");
   }
   assert(cur == max_length() || num_regions == 0 || is_available(cur),
          err_msg("The region at the current position %u must be available or at the end of the heap.", cur));
 #endif
   return num_regions;
 }
 uint HeapRegionManager::start_region_for_worker(uint worker_i, uint num_workers, uint num_regions) const {
   return num_regions * worker_i / num_workers;
 }
 void HeapRegionManager::par_iterate(HeapRegionClosure* blk, uint worker_id, uint num_workers, jint claim_value) const {
   const uint start_index = start_region_for_worker(worker_id, num_workers, _allocated_heapregions_length);
   // Every worker will actually look at all regions, skipping over regions that
   // are currently not committed.
   // This also (potentially) iterates over regions newly allocated during GC. This
   // is no problem except for some extra work.
   for (uint count = 0; count < _allocated_heapregions_length; count++) {
     const uint index = (start_index + count) % _allocated_heapregions_length;
     assert(0 <= index && index < _allocated_heapregions_length, "sanity");
     // Skip over unavailable regions
     if (!is_available(index)) {
       continue;
     }
     HeapRegion* r = _regions.get_by_index(index);
     // We'll ignore "continues humongous" regions (we'll process them
     // when we come across their corresponding "start humongous"
     // region) and regions already claimed.
     if (r->claim_value() == claim_value || r->continuesHumongous()) {
       continue;
     }
     // OK, try to claim it
     if (!r->claimHeapRegion(claim_value)) {
       continue;
     }
     // Success!
     if (r->startsHumongous()) {
       // If the region is "starts humongous" we'll iterate over its
       // "continues humongous" first; in fact we'll do them
       // first. The order is important. In one case, calling the
       // closure on the "starts humongous" region might de-allocate
       // and clear all its "continues humongous" regions and, as a
       // result, we might end up processing them twice. So, we'll do
       // them first (note: most closures will ignore them anyway) and
       // then we'll do the "starts humongous" region.
       for (uint ch_index = index + 1; ch_index < index + r->region_num(); ch_index++) {
         HeapRegion* chr = _regions.get_by_index(ch_index);
         assert(chr->continuesHumongous(), "Must be humongous region");
         assert(chr->humongous_start_region() == r,
                err_msg("Must work on humongous continuation of the original start region "
                        PTR_FORMAT ", but is " PTR_FORMAT, p2i(r), p2i(chr)));
         assert(chr->claim_value() != claim_value,
                "Must not have been claimed yet because claiming of humongous continuation first claims the start region");
         bool claim_result = chr->claimHeapRegion(claim_value);
         // We should always be able to claim it; no one else should
         // be trying to claim this region.
         guarantee(claim_result, "We should always be able to claim the continuesHumongous part of the humongous object");
         bool res2 = blk->doHeapRegion(chr);
         if (res2) {
           return;
         }
         // Right now, this holds (i.e., no closure that actually
         // does something with "continues humongous" regions
         // clears them). We might have to weaken it in the future,
         // but let's leave these two asserts here for extra safety.
         assert(chr->continuesHumongous(), "should still be the case");
         assert(chr->humongous_start_region() == r, "sanity");
       }
     }
     bool res = blk->doHeapRegion(r);
     if (res) {
       return;
     }
   }
 }
 uint HeapRegionManager::shrink_by(uint num_regions_to_remove) {
   assert(length() > 0, "the region sequence should not be empty");
   assert(length() <= _allocated_heapregions_length, "invariant");
   assert(_allocated_heapregions_length > 0, "we should have at least one region committed");
   assert(num_regions_to_remove < length(), "We should never remove all regions");
   if (num_regions_to_remove == 0) {
     return 0;
   }
   uint removed = 0;
   uint cur = _allocated_heapregions_length - 1;
   uint idx_last_found = 0;
   uint num_last_found = 0;
   while ((removed < num_regions_to_remove) &&
       (num_last_found = find_empty_from_idx_reverse(cur, &idx_last_found)) > 0) {
     uint to_remove = MIN2(num_regions_to_remove - removed, num_last_found);
     uncommit_regions(idx_last_found + num_last_found - to_remove, to_remove);
     cur -= num_last_found;
     removed += to_remove;
   }
   verify_optional();
   return removed;
 }
 uint HeapRegionManager::find_empty_from_idx_reverse(uint start_idx, uint* res_idx) const {
   guarantee(start_idx < _allocated_heapregions_length, "checking");
   guarantee(res_idx != NULL, "checking");
   uint num_regions_found = 0;
   jlong cur = start_idx;
   while (cur != -1 && !(is_available(cur) && at(cur)->is_empty())) {
     cur--;
   }
   if (cur == -1) {
     return num_regions_found;
   }
   jlong old_cur = cur;
   // cur indexes the first empty region
   while (cur != -1 && is_available(cur) && at(cur)->is_empty()) {
     cur--;
   }
   *res_idx = cur + 1;
   num_regions_found = old_cur - cur;
 #ifdef ASSERT
   for (uint i = *res_idx; i < (*res_idx + num_regions_found); i++) {
     assert(at(i)->is_empty(), "just checking");
   }
 #endif
   return num_regions_found;
 }
 void HeapRegionManager::verify() {
   guarantee(length() <= _allocated_heapregions_length,
             err_msg("invariant: _length: %u _allocated_length: %u",
                     length(), _allocated_heapregions_length));
   guarantee(_allocated_heapregions_length <= max_length(),
             err_msg("invariant: _allocated_length: %u _max_length: %u",
                     _allocated_heapregions_length, max_length()));
   bool prev_committed = true;
   uint num_committed = 0;
   HeapWord* prev_end = heap_bottom();
   for (uint i = 0; i < _allocated_heapregions_length; i++) {
     if (!is_available(i)) {
       prev_committed = false;
       continue;
     }
     num_committed++;
     HeapRegion* hr = _regions.get_by_index(i);
     guarantee(hr != NULL, err_msg("invariant: i: %u", i));
     guarantee(!prev_committed || hr->bottom() == prev_end,
               err_msg("invariant i: %u "HR_FORMAT" prev_end: "PTR_FORMAT,
                       i, HR_FORMAT_PARAMS(hr), p2i(prev_end)));
     guarantee(hr->hrm_index() == i,
               err_msg("invariant: i: %u hrm_index(): %u", i, hr->hrm_index()));
     // Asserts will fire if i is >= _length
     HeapWord* addr = hr->bottom();
     guarantee(addr_to_region(addr) == hr, "sanity");
     // We cannot check whether the region is part of a particular set: at the time
     // this method may be called, we have only completed allocation of the regions,
     // but not put into a region set.
     prev_committed = true;
     if (hr->startsHumongous()) {
       prev_end = hr->orig_end();
     } else {
       prev_end = hr->end();
     }
   }
   for (uint i = _allocated_heapregions_length; i < max_length(); i++) {
     guarantee(_regions.get_by_index(i) == NULL, err_msg("invariant i: %u", i));
   }
   guarantee(num_committed == _num_committed, err_msg("Found %u committed regions, but should be %u", num_committed, _num_committed));
   _free_list.verify();
 }
 #ifndef PRODUCT
 void HeapRegionManager::verify_optional() {
   verify();
 }
 #endif // PRODUCT

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/heapRegionManager.cpp@c2844108a708 (annotated)

src/share/vm/gc_implementation/g1/heapRegionManager.cpp