Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751938AbYKLEXQ (ORCPT ); Tue, 11 Nov 2008 23:23:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751016AbYKLEXA (ORCPT ); Tue, 11 Nov 2008 23:23:00 -0500 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:48031 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750757AbYKLEW7 (ORCPT ); Tue, 11 Nov 2008 23:22:59 -0500 Date: Wed, 12 Nov 2008 13:22:19 +0900 From: KAMEZAWA Hiroyuki To: nishimura@mxp.nes.nec.co.jp Cc: Daisuke Nishimura , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "balbir@linux.vnet.ibm.com" , "menage@google.com" Subject: Re: [RFC][PATCH 4/6] memcg: swap cgroup for remembering account Message-Id: <20081112132219.20510b57.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20081112131701.dbb7d003.d-nishimura@mtf.biglobe.ne.jp> References: <20081112122606.76051530.kamezawa.hiroyu@jp.fujitsu.com> <20081112122949.d17bbc7f.kamezawa.hiroyu@jp.fujitsu.com> <20081112131701.dbb7d003.d-nishimura@mtf.biglobe.ne.jp> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 2.5.0 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1636 Lines: 60 On Wed, 12 Nov 2008 13:17:01 +0900 Daisuke Nishimura wrote: > > +/** > > + * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry > > + * @ent: swap entry to be looked up. > > + * > > + * Returns pointer to mem_cgroup at success. NULL at failure. > > + */ > > +struct mem_cgroup *lookup_swap_cgroup(swp_entry_t ent) > > +{ > > + int type = swp_type(ent); > > + unsigned long flags; > > + unsigned long offset = swp_offset(ent); > > + unsigned long idx = offset / SC_PER_PAGE; > > + unsigned long pos = offset & SC_POS_MASK; > > + struct swap_cgroup_ctrl *ctrl; > > + struct page *mappage; > > + struct swap_cgroup *sc; > > + struct mem_cgroup *ret; > > + > > + if (!do_swap_account) > > + return NULL; > > + > > + ctrl = &swap_cgroup_ctrl[type]; > > + > > + mappage = ctrl->map[idx]; > > + > > + spin_lock_irqsave(&ctrl->lock, flags); > > + sc = kmap_atomic(mappage, KM_USER0); > > + sc += pos; > > + ret = sc->val; > > + kunmap_atomic(mapppage, KM_USER0); > s/mapppage/mappage > > I don't know why I didn't notice this while testing previous version. > Ah...kmap_atomic() doesn't check its argument if HIGHMEM=n. and mapppage disappears by macro. I'm now preparing x86-32 test enviroment before goint further. Thanks, -Kame > > Thanks, > Daisuke Nishimura. > > > + spin_unlock_irqrestore(&ctrl->lock, flags); > > + return ret; > > +} > > + > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/