From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id E10B96B0027 for ; Wed, 28 Mar 2018 10:49:44 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id c5so1527683pfn.17 for ; Wed, 28 Mar 2018 07:49:44 -0700 (PDT) Received: from EUR03-AM5-obe.outbound.protection.outlook.com (mail-eopbgr30135.outbound.protection.outlook.com. [40.107.3.135]) by mx.google.com with ESMTPS id 75si2560888pga.647.2018.03.28.07.49.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 28 Mar 2018 07:49:43 -0700 (PDT) Subject: Re: [PATCH 06/10] list_lru: Pass dst_memcg argument to memcg_drain_list_lru_node() From: Kirill Tkhai References: <152163840790.21546.980703278415599202.stgit@localhost.localdomain> <152163853059.21546.940468208501917585.stgit@localhost.localdomain> <20180324193253.y653nm4z6sh7u2kd@esperanza> <0fe02df4-3d55-2ee3-95af-156ac63f29be@virtuozzo.com> Message-ID: Date: Wed, 28 Mar 2018 17:49:34 +0300 MIME-Version: 1.0 In-Reply-To: <0fe02df4-3d55-2ee3-95af-156ac63f29be@virtuozzo.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Vladimir Davydov Cc: viro@zeniv.linux.org.uk, hannes@cmpxchg.org, mhocko@kernel.org, akpm@linux-foundation.org, tglx@linutronix.de, pombredanne@nexb.com, stummala@codeaurora.org, gregkh@linuxfoundation.org, sfr@canb.auug.org.au, guro@fb.com, mka@chromium.org, penguin-kernel@I-love.SAKURA.ne.jp, chris@chris-wilson.co.uk, longman@redhat.com, minchan@kernel.org, hillf.zj@alibaba-inc.com, ying.huang@intel.com, mgorman@techsingularity.net, shakeelb@google.com, jbacik@fb.com, linux@roeck-us.net, linux-kernel@vger.kernel.org, linux-mm@kvack.org, willy@infradead.org On 26.03.2018 18:30, Kirill Tkhai wrote: > On 24.03.2018 22:32, Vladimir Davydov wrote: >> On Wed, Mar 21, 2018 at 04:22:10PM +0300, Kirill Tkhai wrote: >>> This is just refactoring to allow next patches to have >>> dst_memcg pointer in memcg_drain_list_lru_node(). >>> >>> Signed-off-by: Kirill Tkhai >>> --- >>> include/linux/list_lru.h | 2 +- >>> mm/list_lru.c | 11 ++++++----- >>> mm/memcontrol.c | 2 +- >>> 3 files changed, 8 insertions(+), 7 deletions(-) >>> >>> diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h >>> index ce1d010cd3fa..50cf8c61c609 100644 >>> --- a/include/linux/list_lru.h >>> +++ b/include/linux/list_lru.h >>> @@ -66,7 +66,7 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, >>> #define list_lru_init_memcg(lru) __list_lru_init((lru), true, NULL) >>> >>> int memcg_update_all_list_lrus(int num_memcgs); >>> -void memcg_drain_all_list_lrus(int src_idx, int dst_idx); >>> +void memcg_drain_all_list_lrus(int src_idx, struct mem_cgroup *dst_memcg); >> >> Please, for consistency pass the source cgroup as a pointer as well. > > Ok Hm. But we call it from memcg_offline_kmem() after cgroup's kmemcg_id is set to parent memcg's kmemcg_id: rcu_read_lock(); /* can be called from css_free w/o cgroup_mutex */ css_for_each_descendant_pre(css, &memcg->css) { child = mem_cgroup_from_css(css); BUG_ON(child->kmemcg_id != kmemcg_id); child->kmemcg_id = parent->kmemcg_id; if (!memcg->use_hierarchy) break; } rcu_read_unlock(); memcg_drain_all_list_lrus(kmemcg_id, parent); It does not seem we may pass memcg to memcg_drain_all_list_lrus() or change the logic or order. What do you think? Kirill