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Date:   Fri, 5 Mar 2021 16:00:19 -0500
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Shakeel Butt <shakeelb@google.com>
Cc:     Hugh Dickins <hughd@google.com>, Roman Gushchin <guro@fb.com>,
        Michal Hocko <mhocko@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Cgroups <cgroups@vger.kernel.org>, Linux MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3] memcg: charge before adding to swapcache on swapin
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On Fri, Mar 05, 2021 at 08:42:00AM -0800, Shakeel Butt wrote:
> On Fri, Mar 5, 2021 at 8:25 AM Johannes Weiner <hannes@cmpxchg.org> wrote:
> >
> [...]
> > I'd also rename cgroup_memory_noswap to cgroup_swapaccount - to match
> > the commandline and (hopefully) make a bit clearer what it effects.
> 
> Do we really need to keep supporting "swapaccount=0"? Is swap
> page_counter really a performance issue for systems with memcg and
> swap? To me, deprecating "swapaccount=0" simplifies already
> complicated code.

Now that you mention it, it's probably really not worth it.

I'll replace my cleanup patch with a removal patch that eliminates
everything behind swapaccount= except for a deprecation warning...