Re: [PATCH] zram: revive swap_slot_free_notify

From: Andrew Morton
Date: Mon Mar 21 2016 - 16:30:24 EST

On Fri, 18 Mar 2016 16:58:31 +0900 Minchan Kim <minchan@xxxxxxxxxx> wrote:

> <b430e9d1c6d4> "remove compressed copy from zram in-memory"
> applied swap_slot_free_notify call in *end_swap_bio_read* to
> remove duplicated memory between zram and memory.
> However, with introducing rw_page in zram <8c7f01025f7b>
> "zram: implement rw_page operation of zram", it became void
> because rw_page doesn't need bio.
> This patch restores the function for rw_page.

This is a bit mysterious. What is the actual runtime effect of the
patch? I assume that 8c7f01025f7b caused duplication of memory and
that the only problem is additional resource consumption? If so, what
are the observable effects? etcetera, please.