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Date:   Thu, 25 Jan 2018 12:03:02 -0500 (EST)
Message-Id: <20180125.120302.1117695034222616751.davem@davemloft.net>
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Subject: Re: [PATCH net] net: memcontrol: charge allocated memory after
 mem_cgroup_sk_alloc()
From:   David Miller <davem@davemloft.net>
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From: Roman Gushchin <guro@fb.com>
Date: Thu, 25 Jan 2018 00:19:11 +0000

> @@ -476,6 +477,10 @@ struct sock *inet_csk_accept(struct sock *sk, int flags, int *err, bool kern)
>  		spin_unlock_bh(&queue->fastopenq.lock);
>  	}
>  	mem_cgroup_sk_alloc(newsk);
> +	amt = sk_memory_allocated(newsk);
> +	if (amt && newsk->sk_memcg)
> +		mem_cgroup_charge_skmem(newsk->sk_memcg, amt);
> +

This looks confusing to me.

sk_memory_allocated() is the total amount of memory used by all
sockets for a particular "struct proto", not just for that specific
socket.

Maybe I don't understand how this socket memcg stuff works, but it
seems like you should be looking instead at how much memory is
allocated to this specific socket.

Thanks.