mm: swap: Use memset to fill the swap_map with SWAP_HAS_CACHE

Quoted 4 lines · On Mon, 21 Sep 2020 08:22:24 -0400 Miaohe Lin <[email protected]> wrote:

We could use helper memset to fill the swap_map with SWAP_HAS_CACHE instead of a direct loop here to simplify the code. Also we can remove the local variable i and map this way.
*slot = swp_entry(si->type, offset);

I suppose so. But it does assume that the ->swapmap array has the type char. If we ever change that, breakage will ensue.