From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <47DE66BE.30904@openvz.org> Date: Mon, 17 Mar 2008 15:40:30 +0300 From: Pavel Emelyanov MIME-Version: 1.0 Subject: Re: [RFC][2/3] Account and control virtual address space allocations References: <20080316172942.8812.56051.sendpatchset@localhost.localdomain> <20080316173005.8812.88290.sendpatchset@localhost.localdomain> <47DE57C2.5060206@openvz.org> <47DE640F.3070601@linux.vnet.ibm.com> In-Reply-To: <47DE640F.3070601@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: balbir@linux.vnet.ibm.com Cc: linux-mm@kvack.org, Hugh Dickins , Sudhir Kumar , YAMAMOTO Takashi , Paul Menage , lizf@cn.fujitsu.com, linux-kernel@vger.kernel.org, taka@valinux.co.jp, David Rientjes , Andrew Morton , KAMEZAWA Hiroyuki List-ID: Balbir Singh wrote: > Pavel Emelyanov wrote: >> [snip] >> >>> +int mem_cgroup_update_as(struct mm_struct *mm, long nr_pages) >>> +{ >>> + int ret = 0; >>> + struct mem_cgroup *mem; >>> + if (mem_cgroup_subsys.disabled) >>> + return ret; >>> + >>> + rcu_read_lock(); >>> + mem = rcu_dereference(mm->mem_cgroup); >>> + css_get(&mem->css); >>> + rcu_read_unlock(); >>> + >>> + if (nr_pages > 0) { >>> + if (res_counter_charge(&mem->as_res, (nr_pages * PAGE_SIZE))) >>> + ret = 1; >>> + } else >>> + res_counter_uncharge(&mem->as_res, (-nr_pages * PAGE_SIZE)); >> No, please, no. Let's make two calls - mem_cgroup_charge_as and mem_cgroup_uncharge_as. >> >> [snip] >> > > Yes, sure :) Thanks :) >>> @@ -1117,6 +1117,9 @@ munmap_back: >>> } >>> } >>> >>> + if (mem_cgroup_update_as(mm, len >> PAGE_SHIFT)) >>> + return -ENOMEM; >>> + >> Why not use existintg cap_vm_enough_memory and co? >> > > I thought about it and almost used may_expand_vm(), but there is a slight catch > there. With cap_vm_enough_memory() or security_vm_enough_memory(), they are > called after total_vm has been calculated. In our case we need to keep the > cgroups equivalent of total_vm up to date, and we do this in mem_cgorup_update_as. So? What prevents us from using these hooks? :) -- 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/ . Don't email: email@kvack.org