From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 7A3116B0031 for ; Thu, 13 Oct 2011 09:11:21 -0400 (EDT) From: Glauber Costa Subject: [PATCH v7 8/8] Disable task moving when using kernel memory accounting Date: Thu, 13 Oct 2011 17:09:42 +0400 Message-Id: <1318511382-31051-9-git-send-email-glommer@parallels.com> In-Reply-To: <1318511382-31051-1-git-send-email-glommer@parallels.com> References: <1318511382-31051-1-git-send-email-glommer@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, lizf@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, ebiederm@xmission.com, davem@davemloft.net, paul@paulmenage.org, gthelen@google.com, netdev@vger.kernel.org, linux-mm@kvack.org, kirill@shutemov.name, avagin@parallels.com, devel@openvz.org, Glauber Costa Since this code is still experimental, we are leaving the exact details of how to move tasks between cgroups when kernel memory accounting is used as future work. For now, we simply disallow movement if there are any pending accounted memory. Signed-off-by: Glauber Costa Reviewed-by: KAMEZAWA Hiroyuki --- mm/memcontrol.c | 31 ++++++++++++++++++------------- 1 files changed, 18 insertions(+), 13 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1ba318d..b46232b 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -408,23 +408,11 @@ void sock_update_memcg(struct sock *sk) 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(); } void sock_release_memcg(struct sock *sk) { - cgroup_release_and_wakeup_rmdir(mem_cgroup_css(sk->sk_cgrp)); } void memcg_sockets_allocated_dec(struct mem_cgroup *memcg, struct proto *prot) @@ -5634,10 +5622,17 @@ static int mem_cgroup_can_attach(struct cgroup_subsys *ss, { int ret = 0; struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); + struct mem_cgroup *from = mem_cgroup_from_task(p); + + if (from != mem && + res_counter_read_u64(&mem->tcp.tcp_memory_allocated, RES_USAGE)) { + printk(KERN_WARNING "Can't move tasks between cgroups: " + "Kernel memory held. task: %s\n", p->comm); + return 1; + } if (mem->move_charge_at_immigrate) { struct mm_struct *mm; - struct mem_cgroup *from = mem_cgroup_from_task(p); VM_BUG_ON(from == mem); @@ -5805,6 +5800,16 @@ static int mem_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgroup, struct task_struct *p) { + struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); + struct mem_cgroup *from = mem_cgroup_from_task(p); + + if (from != mem && + res_counter_read_u64(&mem->tcp.tcp_memory_allocated, RES_USAGE)) { + printk(KERN_WARNING "Can't move tasks between cgroups: " + "Kernel memory held. task: %s\n", p->comm); + return 1; + } + return 0; } static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, -- 1.7.6.4 -- 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