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 SMTP id DE0F48D0039 for ; Mon, 17 Jan 2011 21:49:43 -0500 (EST) Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id AE0FC3EE0AE for ; Tue, 18 Jan 2011 11:49:41 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 8F01045DD74 for ; Tue, 18 Jan 2011 11:49:41 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 7489B45DE55 for ; Tue, 18 Jan 2011 11:49:41 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 654EA1DB803F for ; Tue, 18 Jan 2011 11:49:41 +0900 (JST) Received: from m106.s.css.fujitsu.com (m106.s.css.fujitsu.com [10.249.87.106]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 23EAF1DB803B for ; Tue, 18 Jan 2011 11:49:41 +0900 (JST) Date: Tue, 18 Jan 2011 11:43:48 +0900 From: KAMEZAWA Hiroyuki Subject: [PATCH 4/4] memcg: fix rmdir, force_empty with THP Message-Id: <20110118114348.9e1dba9b.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110118113528.fd24928f.kamezawa.hiroyu@jp.fujitsu.com> References: <20110118113528.fd24928f.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "akpm@linux-foundation.org" , "nishimura@mxp.nes.nec.co.jp" , "balbir@linux.vnet.ibm.com" , "hannes@cmpxchg.org" List-ID: Now, when THP is enabled, memcg's rmdir() function is broken because move_account() for THP page is not supported. This will cause account leak or -EBUSY issue at rmdir(). This patch fixes the issue by supporting move_account() THP pages. Changelog: - style fix. - add compound_lock for avoiding races. Signed-off-by: KAMEZAWA Hiroyuki --- mm/memcontrol.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) Index: mmotm-0107/mm/memcontrol.c =================================================================== --- mmotm-0107.orig/mm/memcontrol.c +++ mmotm-0107/mm/memcontrol.c @@ -2197,8 +2197,11 @@ void mem_cgroup_split_huge_fixup(struct */ static void __mem_cgroup_move_account(struct page_cgroup *pc, - struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge) + struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge, + int charge_size) { + int nr_pages = charge_size >> PAGE_SHIFT; + VM_BUG_ON(from == to); VM_BUG_ON(PageLRU(pc->page)); VM_BUG_ON(!page_is_cgroup_locked(pc)); @@ -2212,14 +2215,14 @@ static void __mem_cgroup_move_account(st __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); preempt_enable(); } - mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -1); + mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); if (uncharge) /* This is not "cancel", but cancel_charge does all we need. */ - mem_cgroup_cancel_charge(from, PAGE_SIZE); + mem_cgroup_cancel_charge(from, charge_size); /* caller should have done css_get */ pc->mem_cgroup = to; - mem_cgroup_charge_statistics(to, PageCgroupCache(pc), 1); + mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); /* * We charges against "to" which may not have any tasks. Then, "to" * can be under rmdir(). But in current implementation, caller of @@ -2234,15 +2237,19 @@ static void __mem_cgroup_move_account(st * __mem_cgroup_move_account() */ static int mem_cgroup_move_account(struct page_cgroup *pc, - struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge) + struct mem_cgroup *from, struct mem_cgroup *to, + bool uncharge, int charge_size) { int ret = -EINVAL; unsigned long flags; + if ((charge_size > PAGE_SIZE) && !PageTransHuge(pc->page)) + return -EBUSY; + lock_page_cgroup(pc); if (PageCgroupUsed(pc) && pc->mem_cgroup == from) { move_lock_page_cgroup(pc, &flags); - __mem_cgroup_move_account(pc, from, to, uncharge); + __mem_cgroup_move_account(pc, from, to, uncharge, charge_size); move_unlock_page_cgroup(pc, &flags); ret = 0; } @@ -2267,6 +2274,8 @@ static int mem_cgroup_move_parent(struct struct cgroup *cg = child->css.cgroup; struct cgroup *pcg = cg->parent; struct mem_cgroup *parent; + int charge = PAGE_SIZE; + unsigned long flags; int ret; /* Is ROOT ? */ @@ -2278,17 +2287,23 @@ static int mem_cgroup_move_parent(struct goto out; if (isolate_lru_page(page)) goto put; + /* The page is isolated from LRU and we have no race with splitting */ + charge = PAGE_SIZE << compound_order(page); parent = mem_cgroup_from_cont(pcg); - ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, - PAGE_SIZE); + ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, charge); if (ret || !parent) goto put_back; - ret = mem_cgroup_move_account(pc, child, parent, true); + if (charge > PAGE_SIZE) + flags = compound_lock_irqsave(page); + + ret = mem_cgroup_move_account(pc, child, parent, true, charge); if (ret) - mem_cgroup_cancel_charge(parent, PAGE_SIZE); + mem_cgroup_cancel_charge(parent, charge); put_back: + if (charge > PAGE_SIZE) + compound_unlock_irqrestore(page, flags); putback_lru_page(page); put: put_page(page); @@ -4868,7 +4883,7 @@ retry: goto put; pc = lookup_page_cgroup(page); if (!mem_cgroup_move_account(pc, - mc.from, mc.to, false)) { + mc.from, mc.to, false, PAGE_SIZE)) { mc.precharge--; /* we uncharge from mc.from later. */ mc.moved_charge++; -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org