From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755531AbXD0Jnp (ORCPT ); Fri, 27 Apr 2007 05:43:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755533AbXD0Jnp (ORCPT ); Fri, 27 Apr 2007 05:43:45 -0400 Received: from mailhub.sw.ru ([195.214.233.200]:38010 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755531AbXD0Jnn (ORCPT ); Fri, 27 Apr 2007 05:43:43 -0400 Message-ID: <4631C69E.5020307@sw.ru> Date: Fri, 27 Apr 2007 13:47:10 +0400 From: Pavel Emelianov User-Agent: Thunderbird 1.5 (X11/20060317) MIME-Version: 1.0 To: balbir@linux.vnet.ibm.com CC: linux kernel mailing list Subject: Re: [PATCH] RSS container, fix freeing of active pages References: <4630F6D2.8040407@linux.vnet.ibm.com> In-Reply-To: <4630F6D2.8040407@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Balbir Singh wrote: > Hi, Pavel, > > I missed you on the list and the patch did not make it to lkml. > I am resending the patch. > > > > > ------------------------------------------------------------------------ > > > > This patch fixes the bad_page() warning seen while freeing a container page. > By default all container pages are added to the active list on the > container. This patch lazily moves pages to the right list, so that a page > on the active list of the zone LRU and the inactive list of the container > does not get freed. If that happens, we see a warning from bad_page(). > > Signed-off-by: Balbir Singh > --- > > linux/rss_container.h | 0 > mm/rss_container.c | 30 ++++++++++++++++++++++-------- > 2 files changed, 22 insertions(+), 8 deletions(-) > > diff -puN mm/rss_container.c~rss-fix-free-of-active-pages mm/rss_container.c > --- linux-2.6.20/mm/rss_container.c~rss-fix-free-of-active-pages 2007-04-25 22:05:54.000000000 +0530 > +++ linux-2.6.20-balbir/mm/rss_container.c 2007-04-25 23:12:35.000000000 +0530 > @@ -119,18 +119,36 @@ void container_rss_move_lists(struct pag > } > > static unsigned long isolate_container_pages(unsigned long nr_to_scan, > - struct list_head *src, struct list_head *dst, > - unsigned long *scanned, struct zone *zone) > + struct rss_container *rss, struct list_head *dst, > + unsigned long *scanned, struct zone *zone, bool active) > { > unsigned long nr_taken = 0; > struct page *page; > struct page_container *pc; > unsigned long scan; > + struct list_head *src; > LIST_HEAD(pc_list); > > + src = active ? &rss->active_list : &rss->inactive_list; > + > for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) { > pc = list_entry(src->prev, struct page_container, list); > page = pc->page; > + > + /* > + * We might have got our active, inactive lists > + * incorrect, fix it here > + */ Hm... Did you see such a situation in your experiments? If yes, then why not fix it in a normal way by moving the pages from list to list where appropriate? > + if (active && !PageActive(page)) { > + list_move(&pc->list, &rss->inactive_list); > + scan--; > + continue; > + } else if (!active && PageActive(page)) { > + list_move(&pc->list, &rss->active_list); > + scan--; > + continue; > + } > + > if (page_zone(page) != zone) > continue; > > @@ -158,12 +176,8 @@ unsigned long isolate_pages_in_container > unsigned long ret; > > spin_lock(&rss->res.lock); > - if (active) > - ret = isolate_container_pages(nr_to_scan, &rss->active_list, > - dst, scanned, zone); > - else > - ret = isolate_container_pages(nr_to_scan, &rss->inactive_list, > - dst, scanned, zone); > + ret = isolate_container_pages(nr_to_scan, rss, dst, scanned, zone, > + active); > spin_unlock(&rss->res.lock); > return ret; > } > diff -puN include/linux/rss_container.h~rss-fix-free-of-active-pages include/linux/rss_container.h > _