From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx106.postini.com [74.125.245.106]) by kanga.kvack.org (Postfix) with SMTP id C5F876B0031 for ; Wed, 3 Jul 2013 12:34:31 -0400 (EDT) Date: Wed, 3 Jul 2013 18:34:29 +0200 From: Michal Hocko Subject: Re: [PATCH next-20130703] net: sock: Add ifdef CONFIG_MEMCG_KMEM for mem_cgroup_sockets_{init,destroy} Message-ID: <20130703163429.GD5153@dhcp22.suse.cz> References: <1372853998-15353-1-git-send-email-sedat.dilek@gmail.com> <51D41E34.5010802@huawei.com> <20130703152058.GA30267@dhcp22.suse.cz> <20130703155958.GC5153@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Sedat Dilek Cc: Li Zefan , akpm@linux-foundation.org, davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-next@vger.kernel.org, sfr@canb.auug.org.au, linux-mm@kvack.org On Wed 03-07-13 18:11:28, Sedat Dilek wrote: > On Wed, Jul 3, 2013 at 5:59 PM, Michal Hocko wrote: > > On Wed 03-07-13 17:53:21, Sedat Dilek wrote: > >> On Wed, Jul 3, 2013 at 5:20 PM, Michal Hocko wrote: > >> > On Wed 03-07-13 20:51:00, Li Zefan wrote: > >> > [...] > >> >> [PATCH] memcg: fix build error if CONFIG_MEMCG_KMEM=n > >> >> > >> >> Fix this build error: > >> >> > >> >> mm/built-in.o: In function `mem_cgroup_css_free': > >> >> memcontrol.c:(.text+0x5caa6): undefined reference to > >> >> 'mem_cgroup_sockets_destroy' > >> >> > >> >> Reported-by: Fengguang Wu > >> >> Reported-by: Stephen Rothwell > >> >> Signed-off-by: Li Zefan > >> > > >> > I am seeing the same thing I just didn't get to reporting it. > >> > The other approach is not bad as well but I find this tiny better > >> > because mem_cgroup_css_free should care only about a single cleanup > >> > function for whole kmem. If that one needs to do tcp kmem specific > >> > cleanup then it should be done inside kmem_cgroup_css_offline. > >> > > >> > >> As said in my other mail, for me this makes sense as it is a followup. > >> > >> But, still I don't know why sock.c has is own mem_cgroup_sockets_{init,destroy}. > > > > That is the only definition AFAICS (except for !CONFIG_NET where it > > expands to NOOP). Please note that memcg_init_kmem is a common kmem > > initializator and it needs to be prepared for !CONFIG_NET. > > > > The same applies to _destroy. > > Makes more sense now? > > > > So, that stuff comes originally from the net-tree. No, it all came from tcp kmem accounting. It is a memcg thingy and I guess it was placed into sock.c because it depends on some static symbols there (e.g. proto_list_mutex). > I understand the !CONFIG_NET case, but lack the understanding why > memcontrol.c needs _destroy. Because it is memcg specific and it has to be called when a group is destroyed. > Can you explain that (sorry /me is no mm-geek)? > > - Sedat - > > [1] http://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/net/core/sock.c?id=next-20130703#n147 > [2] http://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/include/net/sock.h?id=next-20130703#n73 > > > [...] > > -- > > Michal Hocko > > SUSE Labs -- Michal Hocko SUSE Labs -- 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