From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id CAC2F9000F0 for ; Mon, 3 Oct 2011 06:47:35 -0400 (EDT) Date: Mon, 3 Oct 2011 13:47:33 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH v4 2/8] socket: initial cgroup code. Message-ID: <20111003104733.GB29312@shutemov.name> References: <1317637123-18306-1-git-send-email-glommer@parallels.com> <1317637123-18306-3-git-send-email-glommer@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1317637123-18306-3-git-send-email-glommer@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: linux-kernel@vger.kernel.org, paul@paulmenage.org, lizf@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, ebiederm@xmission.com, davem@davemloft.net, gthelen@google.com, netdev@vger.kernel.org, linux-mm@kvack.org, avagin@parallels.com On Mon, Oct 03, 2011 at 02:18:37PM +0400, Glauber Costa wrote: > We aim to control the amount of kernel memory pinned at any > time by tcp sockets. To lay the foundations for this work, > this patch adds a pointer to the kmem_cgroup to the socket > structure. > > Signed-off-by: Glauber Costa > CC: David S. Miller > CC: Hiroyouki Kamezawa > CC: Eric W. Biederman > --- > include/linux/memcontrol.h | 15 +++++++++++++++ > include/net/sock.h | 2 ++ > mm/memcontrol.c | 33 +++++++++++++++++++++++++++++++++ > net/core/sock.c | 3 +++ > 4 files changed, 53 insertions(+), 0 deletions(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index 3b535db..2cb9226 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -395,5 +395,20 @@ mem_cgroup_print_bad_page(struct page *page) > } > #endif > > +#ifdef CONFIG_INET > +struct sock; > +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM > +void sock_update_memcg(struct sock *sk); > +void sock_release_memcg(struct sock *sk); > + > +#else > +static inline void sock_update_memcg(struct sock *sk) > +{ > +} > +static inline void sock_release_memcg(struct sock *sk) > +{ > +} > +#endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ > +#endif /* CONFIG_INET */ > #endif /* _LINUX_MEMCONTROL_H */ > > diff --git a/include/net/sock.h b/include/net/sock.h > index 8e4062f..afe1467 100644 > --- a/include/net/sock.h > +++ b/include/net/sock.h > @@ -228,6 +228,7 @@ struct sock_common { > * @sk_security: used by security modules > * @sk_mark: generic packet mark > * @sk_classid: this socket's cgroup classid > + * @sk_cgrp: this socket's kernel memory (kmem) cgroup > * @sk_write_pending: a write to stream socket waits to start > * @sk_state_change: callback to indicate change in the state of the sock > * @sk_data_ready: callback to indicate there is data to be processed > @@ -339,6 +340,7 @@ struct sock { > #endif > __u32 sk_mark; > u32 sk_classid; > + struct mem_cgroup *sk_cgrp; > void (*sk_state_change)(struct sock *sk); > void (*sk_data_ready)(struct sock *sk, int bytes); > void (*sk_write_space)(struct sock *sk); > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 8aaf4ce..08a520e 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -339,6 +339,39 @@ struct mem_cgroup { > spinlock_t pcp_counter_lock; > }; > > +/* Writing them here to avoid exposing memcg's inner layout */ > +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM > +#ifdef CONFIG_INET > +#include > + > +void sock_update_memcg(struct sock *sk) > +{ > + /* right now a socket spends its whole life in the same cgroup */ > + BUG_ON(sk->sk_cgrp); Do we really want to panic in this case? What about WARN() + return? Otherwise: Acked-by: Kirill A. Shutemov > + > + rcu_read_lock(); > + sk->sk_cgrp = mem_cgroup_from_task(current); > + > + /* > + * We don't need to protect against anything task-related, because > + * we are basically stuck with the sock pointer that won't change, > + * even if the task that originated the socket changes cgroups. > + * > + * What we do have to guarantee, is that the chain leading us to > + * the top level won't change under our noses. Incrementing the > + * reference count via cgroup_exclude_rmdir guarantees that. > + */ > + cgroup_exclude_rmdir(mem_cgroup_css(sk->sk_cgrp)); > + rcu_read_unlock(); > +} -- Kirill A. Shutemov -- 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