From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v2 4/6] slab: add SLAB_ACCOUNT flag
Date: Wed, 11 Nov 2015 10:54:50 -0500
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To: Vladimir Davydov <vdavydov-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org>
Cc: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Michal Hocko <mhocko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Greg Thelen <gthelen-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Christoph Lameter <cl-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org>, Pekka Enberg <penberg-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, David Rientjes <rientjes-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Joonsoo Kim <iamjoonsoo.kim-Hm3cg6mZ9cc@public.gmane.org>, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

Hello,

On Tue, Nov 10, 2015 at 09:54:01PM +0300, Vladimir Davydov wrote:
> > Am I correct in thinking that we should eventually be able to removed
> > __GFP_ACCOUNT and that only caches explicitly marked with SLAB_ACCOUNT
> > would need to be handled by kmemcg?
> 
> Don't think so, because sometimes we want to account kmalloc.

I'm kinda skeptical about that because if those allocations are
occassional by nature, we don't care and if there can be a huge number
of them, splitting them into a separate cache makes sense.  I think it
makes sense to pin down exactly which caches are memcg managed.  That
has the potential to simplify the involved code path and shave off a
small bit of hot path overhead.

Thanks.

-- 
tejun