コード例 #1
0
bool ReservedMemoryRegion::remove_uncommitted_region(address addr, size_t sz) {
  // uncommit stack guard pages
  if (flag() == mtThreadStack && !same_region(addr, sz)) {
    return true;
  }

  assert(addr != NULL, "Invalid address");
  assert(sz > 0, "Invalid size");

  if (all_committed()) {
    assert(_committed_regions.is_empty(), "Sanity check");
    assert(contain_region(addr, sz), "Reserved region does not contain this region");
    set_all_committed(false);
    VirtualMemorySummary::record_uncommitted_memory(sz, flag());
    if (same_region(addr, sz)) {
      return true;
    } else {
      CommittedMemoryRegion rgn(base(), size(), *call_stack());
      if (rgn.base() == addr || rgn.end() == (addr + sz)) {
        rgn.exclude_region(addr, sz);
        return add_committed_region(rgn);
      } else {
        // split this region
        // top of the whole region
        address top =rgn.end();
        // use this region for lower part
        size_t exclude_size = rgn.end() - addr;
        rgn.exclude_region(addr, exclude_size);
        if (add_committed_region(rgn)) {
          // higher part
          address high_base = addr + sz;
          size_t  high_size = top - high_base;
          CommittedMemoryRegion high_rgn(high_base, high_size, NativeCallStack::EMPTY_STACK);
          return add_committed_region(high_rgn);
        } else {
          return false;
        }
      }
    }
  } else {
    // we have to walk whole list to remove the committed regions in
    // specified range
    LinkedListNode<CommittedMemoryRegion>* head =
      _committed_regions.head();
    LinkedListNode<CommittedMemoryRegion>* prev = NULL;
    VirtualMemoryRegion uncommitted_rgn(addr, sz);

    while (head != NULL && !uncommitted_rgn.is_empty()) {
      CommittedMemoryRegion* crgn = head->data();
      // this committed region overlaps to region to uncommit
      if (crgn->overlap_region(uncommitted_rgn.base(), uncommitted_rgn.size())) {
        if (crgn->same_region(uncommitted_rgn.base(), uncommitted_rgn.size())) {
          // find matched region, remove the node will do
          VirtualMemorySummary::record_uncommitted_memory(uncommitted_rgn.size(), flag());
          _committed_regions.remove_after(prev);
          return true;
        } else if (crgn->contain_region(uncommitted_rgn.base(), uncommitted_rgn.size())) {
          // this committed region contains whole uncommitted region
          VirtualMemorySummary::record_uncommitted_memory(uncommitted_rgn.size(), flag());
          return remove_uncommitted_region(head, uncommitted_rgn.base(), uncommitted_rgn.size());
        } else if (uncommitted_rgn.contain_region(crgn->base(), crgn->size())) {
          // this committed region has been uncommitted
          size_t exclude_size = crgn->end() - uncommitted_rgn.base();
          uncommitted_rgn.exclude_region(uncommitted_rgn.base(), exclude_size);
          VirtualMemorySummary::record_uncommitted_memory(crgn->size(), flag());
          LinkedListNode<CommittedMemoryRegion>* tmp = head;
          head = head->next();
          _committed_regions.remove_after(prev);
          continue;
        } else if (crgn->contain_address(uncommitted_rgn.base())) {
          size_t toUncommitted = crgn->end() - uncommitted_rgn.base();
          crgn->exclude_region(uncommitted_rgn.base(), toUncommitted);
          uncommitted_rgn.exclude_region(uncommitted_rgn.base(), toUncommitted);
          VirtualMemorySummary::record_uncommitted_memory(toUncommitted, flag());
        } else if (uncommitted_rgn.contain_address(crgn->base())) {
          size_t toUncommitted = uncommitted_rgn.end() - crgn->base();
          crgn->exclude_region(crgn->base(), toUncommitted);
          uncommitted_rgn.exclude_region(uncommitted_rgn.end() - toUncommitted,
            toUncommitted);
          VirtualMemorySummary::record_uncommitted_memory(toUncommitted, flag());
        }
      }
      prev = head;
      head = head->next();
    }
  }

  return true;
}
コード例 #2
0
bool ReservedMemoryRegion::remove_uncommitted_region(address addr, size_t sz) {
  // uncommit stack guard pages
  if (flag() == mtThreadStack && !same_region(addr, sz)) {
    return true;
  }

  assert(addr != NULL, "Invalid address");
  assert(sz > 0, "Invalid size");

  if (all_committed()) {
    assert(_committed_regions.is_empty(), "Sanity check");
    assert(contain_region(addr, sz), "Reserved region does not contain this region");
    set_all_committed(false);
    VirtualMemorySummary::record_uncommitted_memory(sz, flag());
    if (same_region(addr, sz)) {
      return true;
    } else {
      CommittedMemoryRegion rgn(base(), size(), *call_stack());
      if (rgn.base() == addr || rgn.end() == (addr + sz)) {
        rgn.exclude_region(addr, sz);
        return add_committed_region(rgn);
      } else {
        // split this region
        // top of the whole region
        address top =rgn.end();
        // use this region for lower part
        size_t exclude_size = rgn.end() - addr;
        rgn.exclude_region(addr, exclude_size);
        if (add_committed_region(rgn)) {
          // higher part
          address high_base = addr + sz;
          size_t  high_size = top - high_base;
          CommittedMemoryRegion high_rgn(high_base, high_size, NativeCallStack::EMPTY_STACK);
          return add_committed_region(high_rgn);
        } else {
          return false;
        }
      }
    }
  } else {
    CommittedMemoryRegion del_rgn(addr, sz, *call_stack());
    address end = addr + sz;

    LinkedListNode<CommittedMemoryRegion>* head = _committed_regions.head();
    LinkedListNode<CommittedMemoryRegion>* prev = NULL;
    CommittedMemoryRegion* crgn;

    while (head != NULL) {
      crgn = head->data();

      if (crgn->same_region(addr, sz)) {
        VirtualMemorySummary::record_uncommitted_memory(crgn->size(), flag());
          _committed_regions.remove_after(prev);
          return true;
      }

      // del_rgn contains crgn
      if (del_rgn.contain_region(crgn->base(), crgn->size())) {
          VirtualMemorySummary::record_uncommitted_memory(crgn->size(), flag());
          head = head->next();
          _committed_regions.remove_after(prev);
        continue;  // don't update head or prev
        }

      // Found addr in the current crgn. There are 2 subcases:
      if (crgn->contain_address(addr)) {

        // (1) Found addr+size in current crgn as well. (del_rgn is contained in crgn)
        if (crgn->contain_address(end - 1)) {
          VirtualMemorySummary::record_uncommitted_memory(sz, flag());
          return remove_uncommitted_region(head, addr, sz); // done!
        } else {
          // (2) Did not find del_rgn's end in crgn.
          size_t size = crgn->end() - del_rgn.base();
          crgn->exclude_region(addr, size);
          VirtualMemorySummary::record_uncommitted_memory(size, flag());
      }

      } else if (crgn->contain_address(end - 1)) {
      // Found del_rgn's end, but not its base addr.
        size_t size = del_rgn.end() - crgn->base();
        crgn->exclude_region(crgn->base(), size);
        VirtualMemorySummary::record_uncommitted_memory(size, flag());
        return true;  // should be done if the list is sorted properly!
      }

      prev = head;
      head = head->next();
    }
  }

  return true;
}