Re: [PATCH v3 01/19] mm: memcg: factor out memcg- and lruvec-level changes out of __mod_lruvec_state()

From: Johannes Weiner
Date: Thu May 07 2020 - 16:33:53 EST


On Wed, Apr 22, 2020 at 01:46:50PM -0700, Roman Gushchin wrote:
> To convert memcg and lruvec slab counters to bytes there must be
> a way to change these counters without touching node counters.
> Factor out __mod_memcg_lruvec_state() out of __mod_lruvec_state().
>
> Signed-off-by: Roman Gushchin <guro@xxxxxx>

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>

Roman and I have talked a bunch about the function names here. They're
not optimal, with mod_lruvec_state() doing the entire intersection -
node, memcg, lruvec - and mod_memcg_lruvec_state() being a specific
version that does not update the node.

However, the usecases for mod_memcg_lruvec_state() are highly
specific, so the function won't be widely used. As such, it received
the longer name, and we get to keep the shorter mod_lruvec_state() for
the much more widely used function.