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From: David Miller <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
Subject: Re: [PATCH 5/8] mm: memcontrol: account socket memory on unified
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Date: Tue, 27 Oct 2015 06:49:16 -0700 (PDT)
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From: Michal Hocko <mhocko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Date: Tue, 27 Oct 2015 13:26:47 +0100

> On Mon 26-10-15 12:56:19, Johannes Weiner wrote:
> [...]
>> Or any other combination of pick-and-choose consumers. But
>> honestly, nowadays all our paths are lockless, and the counting is an
>> atomic-add-return with a per-cpu batch cache.
> 
> You are still hooking into hot paths and there are users who want to
> squeeze every single cycle from the HW.

Yeah, you're basically probably undoing a half year of work by another
developer who was able to remove an atomic from these paths.