bool flush()

in src/mem/corealloc.h [831:876]
38 lines of code
5 McCabe index (conditional complexity)

    bool flush(bool destroy_queue = false)
    {
      SNMALLOC_ASSERT(attached_cache != nullptr);
      auto local_state = backend_state_ptr();
      auto domesticate =
        [local_state](freelist::QueuePtr p) SNMALLOC_FAST_PATH_LAMBDA {
          return capptr_domesticate<SharedStateHandle>(local_state, p);
        };

      if (destroy_queue)
      {
        auto p_wild = message_queue().destroy();
        auto p_tame = domesticate(p_wild);

        while (p_tame != nullptr)
        {
          bool need_post = true; // Always going to post, so ignore.
          auto n_tame = p_tame->atomic_read_next(key_global, domesticate);
          auto& entry = SharedStateHandle::Pagemap::get_metaentry(
            backend_state_ptr(), snmalloc::address_cast(p_tame));
          handle_dealloc_remote(entry, p_tame.as_void(), need_post);
          p_tame = n_tame;
        }
      }
      else
      {
        // Process incoming message queue
        // Loop as normally only processes a batch
        while (has_messages())
          handle_message_queue([]() {});
      }

      auto posted =
        attached_cache->flush<sizeof(CoreAllocator), SharedStateHandle>(
          backend_state_ptr(),
          [&](capptr::Alloc<void> p) { dealloc_local_object(p); });

      // We may now have unused slabs, return to the global allocator.
      for (smallsizeclass_t sizeclass = 0; sizeclass < NUM_SMALL_SIZECLASSES;
           sizeclass++)
      {
        dealloc_local_slabs<true>(sizeclass);
      }

      return posted;
    }