Re: [PATCH 8/8] af_unix: charge buffers to kmemcg

From: Vladimir Davydov
Date: Tue May 24 2016 - 03:56:44 EST


[adding netdev to Cc]

On Mon, May 23, 2016 at 01:20:29PM +0300, Vladimir Davydov wrote:
> Unix sockets can consume a significant amount of system memory, hence
> they should be accounted to kmemcg.
>
> Since unix socket buffers are always allocated from process context,
> all we need to do to charge them to kmemcg is set __GFP_ACCOUNT in
> sock->sk_allocation mask.
>
> Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> ---
> net/unix/af_unix.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index 80aa6a3e6817..022bdd3ab7d9 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -769,6 +769,7 @@ static struct sock *unix_create1(struct net *net, struct socket *sock, int kern)
> lockdep_set_class(&sk->sk_receive_queue.lock,
> &af_unix_sk_receive_queue_lock_key);
>
> + sk->sk_allocation = GFP_KERNEL_ACCOUNT;
> sk->sk_write_space = unix_write_space;
> sk->sk_max_ack_backlog = net->unx.sysctl_max_dgram_qlen;
> sk->sk_destruct = unix_sock_destructor;