Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Sat, 2 Apr 2022 01:01:58 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Roman Gushchin <roman.gushchin@linux.dev>
Cc:     Florian Westphal <fw@strlen.de>,
        Vasily Averin <vasily.averin@linux.dev>,
        Pablo Neira Ayuso <pablo@netfilter.org>, kernel@openvz.org,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH nft] nft: memcg accounting for dynamically allocated
 objects
Message-ID: <20220401230158.GC28321@breakpoint.cc>
References: <bf4b8fe3-6dd6-4f3a-12f4-1b5bf2e45783@linux.dev>
 <e730480d-9396-6486-ab98-67ecb683e819@linux.dev>
 <20220401120342.GC9545@breakpoint.cc>
 <7bfa2e2e-b22d-7561-661b-41ef7714caf5@linux.dev>
 <20220401193159.GB28321@breakpoint.cc>
 <YkdrRAiO1P7segcd@carbon.dhcp.thefacebook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YkdrRAiO1P7segcd@carbon.dhcp.thefacebook.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

Roman Gushchin <roman.gushchin@linux.dev> wrote:
> On Fri, Apr 01, 2022 at 09:31:59PM +0200, Florian Westphal wrote:
> > But what task/memcg is used for the accounting in that case?
> 
> Root memcg/no accounting, which is the same.
> 
> There is a way to account for a specific memcg in such cases, it's used for
> bpf maps, for example. We save a pointer to the memcg which created the map and
> charge it for all allocations from a !in_task context.

Great, so we could use same scheme later on if its required for some
use case.

>  so let's not do without regression tests and a serious need.

Sounds good. Thanks.