From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx173.postini.com [74.125.245.173]) by kanga.kvack.org (Postfix) with SMTP id 35B606B004D for ; Thu, 22 Dec 2011 16:10:45 -0500 (EST) Date: Thu, 22 Dec 2011 16:10:29 -0500 From: Jason Baron Subject: Re: [PATCH v9 3/9] socket: initial cgroup code. Message-ID: <20111222211028.GB3916@redhat.com> References: <1323676029-5890-1-git-send-email-glommer@parallels.com> <1323676029-5890-4-git-send-email-glommer@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1323676029-5890-4-git-send-email-glommer@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: davem@davemloft.net, linux-kernel@vger.kernel.org, paul@paulmenage.org, lizf@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, ebiederm@xmission.com, gthelen@google.com, netdev@vger.kernel.org, linux-mm@kvack.org, kirill@shutemov.name, avagin@parallels.com, devel@openvz.org, eric.dumazet@gmail.com, cgroups@vger.kernel.org On Mon, Dec 12, 2011 at 11:47:03AM +0400, Glauber Costa wrote: > + > +static bool mem_cgroup_is_root(struct mem_cgroup *memcg); > +void sock_update_memcg(struct sock *sk) > +{ > + /* A socket spends its whole life in the same cgroup */ > + if (sk->sk_cgrp) { > + WARN_ON(1); > + return; > + } > + if (static_branch(&memcg_socket_limit_enabled)) { > + struct mem_cgroup *memcg; > + > + BUG_ON(!sk->sk_prot->proto_cgroup); > + > + rcu_read_lock(); > + memcg = mem_cgroup_from_task(current); > + if (!mem_cgroup_is_root(memcg)) { > + mem_cgroup_get(memcg); > + sk->sk_cgrp = sk->sk_prot->proto_cgroup(memcg); > + } > + rcu_read_unlock(); > + } > +} > +EXPORT_SYMBOL(sock_update_memcg); > + > +void sock_release_memcg(struct sock *sk) > +{ > + if (static_branch(&memcg_socket_limit_enabled) && sk->sk_cgrp) { > + struct mem_cgroup *memcg; > + WARN_ON(!sk->sk_cgrp->memcg); > + memcg = sk->sk_cgrp->memcg; > + mem_cgroup_put(memcg); > + } > +} Hi Glauber, I think for 'sock_release_memcg()', you want: static inline sock_release_memcg(sk) { if (static_branch()) __sock_release_memcg(); } And then re-define the current sock_release_memcg -> __sock_release_memcg(). In that way the straight line path is a single no-op. As currently written, there is function call and then an immediate return. Thanks, -Jason -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org