jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/heapRegionSeq.cpp@8a5ea0a9ccc4 (annotated)

src/share/vm/gc_implementation/g1/heapRegionSeq.cpp@8a5ea0a9ccc4 (annotated)

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

Sat, 06 Oct 2012 01:17:44 -0700

author: johnc
date: Sat, 06 Oct 2012 01:17:44 -0700
changeset 4173: 8a5ea0a9ccc4
parent 3900: d2a62e0f25eb
child 5074: b0d20fa374b4
permissions: -rw-r--r--

7127708: G1: change task num types from int to uint in concurrent mark
Summary: Change the type of various task num fields, parameters etc to unsigned and rename them to be more consistent with the other collectors. Code changes were also reviewed by Vitaly Davidovich.
Reviewed-by: johnc
Contributed-by: Kaushik Srenevasan <kaushik@twitter.com>

 /*
  * Copyright (c) 2001, 2012, 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/heapRegionSeq.inline.hpp"
 #include "gc_implementation/g1/heapRegionSets.hpp"
 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
 #include "memory/allocation.hpp"
 // Private
 uint HeapRegionSeq::find_contiguous_from(uint from, uint num) {
   uint len = length();
   assert(num > 1, "use this only for sequences of length 2 or greater");
   assert(from <= len,
          err_msg("from: %u should be valid and <= than %u", from, len));
   uint curr = from;
   uint first = G1_NULL_HRS_INDEX;
   uint num_so_far = 0;
   while (curr < len && num_so_far < num) {
     if (at(curr)->is_empty()) {
       if (first == G1_NULL_HRS_INDEX) {
         first = curr;
         num_so_far = 1;
       } else {
         num_so_far += 1;
       }
     } else {
       first = G1_NULL_HRS_INDEX;
       num_so_far = 0;
     }
     curr += 1;
   }
   assert(num_so_far <= num, "post-condition");
   if (num_so_far == num) {
     // we found enough space for the humongous object
     assert(from <= first && first < len, "post-condition");
     assert(first < curr && (curr - first) == num, "post-condition");
     for (uint i = first; i < first + num; ++i) {
       assert(at(i)->is_empty(), "post-condition");
     }
     return first;
   } else {
     // we failed to find enough space for the humongous object
     return G1_NULL_HRS_INDEX;
   }
 }
 // Public
 void HeapRegionSeq::initialize(HeapWord* bottom, HeapWord* end,
                                uint max_length) {
   assert((uintptr_t) bottom % HeapRegion::GrainBytes == 0,
          "bottom should be heap region aligned");
   assert((uintptr_t) end % HeapRegion::GrainBytes == 0,
          "end should be heap region aligned");
   _length = 0;
   _heap_bottom = bottom;
   _heap_end = end;
   _region_shift = HeapRegion::LogOfHRGrainBytes;
   _next_search_index = 0;
   _allocated_length = 0;
   _max_length = max_length;
   _regions = NEW_C_HEAP_ARRAY(HeapRegion*, max_length, mtGC);
   memset(_regions, 0, (size_t) max_length * sizeof(HeapRegion*));
   _regions_biased = _regions - ((uintx) bottom >> _region_shift);
   assert(&_regions[0] == &_regions_biased[addr_to_index_biased(bottom)],
          "bottom should be included in the region with index 0");
 }
 MemRegion HeapRegionSeq::expand_by(HeapWord* old_end,
                                    HeapWord* new_end,
                                    FreeRegionList* list) {
   assert(old_end < new_end, "don't call it otherwise");
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   HeapWord* next_bottom = old_end;
   assert(_heap_bottom <= next_bottom, "invariant");
   while (next_bottom < new_end) {
     assert(next_bottom < _heap_end, "invariant");
     uint index = length();
     assert(index < _max_length, "otherwise we cannot expand further");
     if (index == 0) {
       // We have not allocated any regions so far
       assert(next_bottom == _heap_bottom, "invariant");
     } else {
       // next_bottom should match the end of the last/previous region
       assert(next_bottom == at(index - 1)->end(), "invariant");
     }
     if (index == _allocated_length) {
       // We have to allocate a new HeapRegion.
       HeapRegion* new_hr = g1h->new_heap_region(index, next_bottom);
       if (new_hr == NULL) {
         // allocation failed, we bail out and return what we have done so far
         return MemRegion(old_end, next_bottom);
       }
       assert(_regions[index] == NULL, "invariant");
       _regions[index] = new_hr;
       increment_length(&_allocated_length);
     }
     // Have to increment the length first, otherwise we will get an
     // assert failure at(index) below.
     increment_length(&_length);
     HeapRegion* hr = at(index);
     list->add_as_tail(hr);
     next_bottom = hr->end();
   }
   assert(next_bottom == new_end, "post-condition");
   return MemRegion(old_end, next_bottom);
 }
 uint HeapRegionSeq::free_suffix() {
   uint res = 0;
   uint index = length();
   while (index > 0) {
     index -= 1;
     if (!at(index)->is_empty()) {
       break;
     }
     res += 1;
   }
   return res;
 }
 uint HeapRegionSeq::find_contiguous(uint num) {
   assert(num > 1, "use this only for sequences of length 2 or greater");
   assert(_next_search_index <= length(),
          err_msg("_next_search_index: %u should be valid and <= than %u",
                  _next_search_index, length()));
   uint start = _next_search_index;
   uint res = find_contiguous_from(start, num);
   if (res == G1_NULL_HRS_INDEX && start > 0) {
     // Try starting from the beginning. If _next_search_index was 0,
     // no point in doing this again.
     res = find_contiguous_from(0, num);
   }
   if (res != G1_NULL_HRS_INDEX) {
     assert(res < length(), err_msg("res: %u should be valid", res));
     _next_search_index = res + num;
     assert(_next_search_index <= length(),
            err_msg("_next_search_index: %u should be valid and <= than %u",
                    _next_search_index, length()));
   }
   return res;
 }
 void HeapRegionSeq::iterate(HeapRegionClosure* blk) const {
   iterate_from((HeapRegion*) NULL, blk);
 }
 void HeapRegionSeq::iterate_from(HeapRegion* hr, HeapRegionClosure* blk) const {
   uint hr_index = 0;
   if (hr != NULL) {
     hr_index = hr->hrs_index();
   }
   uint len = length();
   for (uint i = hr_index; i < len; i += 1) {
     bool res = blk->doHeapRegion(at(i));
     if (res) {
       blk->incomplete();
       return;
     }
   }
   for (uint i = 0; i < hr_index; i += 1) {
     bool res = blk->doHeapRegion(at(i));
     if (res) {
       blk->incomplete();
       return;
     }
   }
 }
 MemRegion HeapRegionSeq::shrink_by(size_t shrink_bytes,
                                    uint* num_regions_deleted) {
   // Reset this in case it's currently pointing into the regions that
   // we just removed.
   _next_search_index = 0;
   assert(shrink_bytes % os::vm_page_size() == 0, "unaligned");
   assert(shrink_bytes % HeapRegion::GrainBytes == 0, "unaligned");
   assert(length() > 0, "the region sequence should not be empty");
   assert(length() <= _allocated_length, "invariant");
   assert(_allocated_length > 0, "we should have at least one region committed");
   // around the loop, i will be the next region to be removed
   uint i = length() - 1;
   assert(i > 0, "we should never remove all regions");
   // [last_start, end) is the MemRegion that covers the regions we will remove.
   HeapWord* end = at(i)->end();
   HeapWord* last_start = end;
   *num_regions_deleted = 0;
   while (shrink_bytes > 0) {
     HeapRegion* cur = at(i);
     // We should leave the humongous regions where they are.
     if (cur->isHumongous()) break;
     // We should stop shrinking if we come across a non-empty region.
     if (!cur->is_empty()) break;
     i -= 1;
     *num_regions_deleted += 1;
     shrink_bytes -= cur->capacity();
     last_start = cur->bottom();
     decrement_length(&_length);
     // We will reclaim the HeapRegion. _allocated_length should be
     // covering this index. So, even though we removed the region from
     // the active set by decreasing _length, we still have it
     // available in the future if we need to re-use it.
     assert(i > 0, "we should never remove all regions");
     assert(length() > 0, "we should never remove all regions");
   }
   return MemRegion(last_start, end);
 }
 #ifndef PRODUCT
 void HeapRegionSeq::verify_optional() {
   guarantee(_length <= _allocated_length,
             err_msg("invariant: _length: %u _allocated_length: %u",
                     _length, _allocated_length));
   guarantee(_allocated_length <= _max_length,
             err_msg("invariant: _allocated_length: %u _max_length: %u",
                     _allocated_length, _max_length));
   guarantee(_next_search_index <= _length,
             err_msg("invariant: _next_search_index: %u _length: %u",
                     _next_search_index, _length));
   HeapWord* prev_end = _heap_bottom;
   for (uint i = 0; i < _allocated_length; i += 1) {
     HeapRegion* hr = _regions[i];
     guarantee(hr != NULL, err_msg("invariant: i: %u", i));
     guarantee(hr->bottom() == prev_end,
               err_msg("invariant i: %u "HR_FORMAT" prev_end: "PTR_FORMAT,
                       i, HR_FORMAT_PARAMS(hr), prev_end));
     guarantee(hr->hrs_index() == i,
               err_msg("invariant: i: %u hrs_index(): %u", i, hr->hrs_index()));
     if (i < _length) {
       // Asserts will fire if i is >= _length
       HeapWord* addr = hr->bottom();
       guarantee(addr_to_region(addr) == hr, "sanity");
       guarantee(addr_to_region_unsafe(addr) == hr, "sanity");
     } else {
       guarantee(hr->is_empty(), "sanity");
       guarantee(!hr->isHumongous(), "sanity");
       // using assert instead of guarantee here since containing_set()
       // is only available in non-product builds.
       assert(hr->containing_set() == NULL, "sanity");
     }
     if (hr->startsHumongous()) {
       prev_end = hr->orig_end();
     } else {
       prev_end = hr->end();
     }
   }
   for (uint i = _allocated_length; i < _max_length; i += 1) {
     guarantee(_regions[i] == NULL, err_msg("invariant i: %u", i));
   }
 }
 #endif // PRODUCT

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/heapRegionSeq.cpp@8a5ea0a9ccc4 (annotated)

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