void MMLru::Container::updateLruInsertionPoint()

in cachelib/allocator/MMLru-inl.h [159:198]

• 31 lines of code
• 9 McCabe index (conditional complexity)

void MMLru::Container<T, HookPtr>::updateLruInsertionPoint() noexcept {
  if (config_.lruInsertionPointSpec == 0) {
    return;
  }

  // If insertionPoint_ is nullptr initialize it to tail first
  if (insertionPoint_ == nullptr) {
    insertionPoint_ = lru_.getTail();
    tailSize_ = 0;
    if (insertionPoint_ != nullptr) {
      markTail(*insertionPoint_);
      tailSize_++;
    }
  }

  if (lru_.size() <= 1) {
    // we are done;
    return;
  }

  XDCHECK_NE(reinterpret_cast<uintptr_t>(nullptr),
             reinterpret_cast<uintptr_t>(insertionPoint_));

  const auto expectedSize = lru_.size() >> config_.lruInsertionPointSpec;
  auto curr = insertionPoint_;

  while (tailSize_ < expectedSize && curr != lru_.getHead()) {
    curr = lru_.getPrev(*curr);
    markTail(*curr);
    tailSize_++;
  }

  while (tailSize_ > expectedSize && curr != lru_.getTail()) {
    unmarkTail(*curr);
    tailSize_--;
    curr = lru_.getNext(*curr);
  }

  insertionPoint_ = curr;
}