From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932216AbWHBUNo (ORCPT ); Wed, 2 Aug 2006 16:13:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932213AbWHBUNo (ORCPT ); Wed, 2 Aug 2006 16:13:44 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:15014 "EHLO ogre.sisk.pl") by vger.kernel.org with ESMTP id S932217AbWHBUNn convert rfc822-to-8bit (ORCPT ); Wed, 2 Aug 2006 16:13:43 -0400 From: "Rafael J. Wysocki" To: Dave Hansen Subject: Re: [PATCH 1/3] swsusp: Fix mark_free_pages Date: Wed, 2 Aug 2006 22:12:48 +0200 User-Agent: KMail/1.9.3 Cc: Andrew Morton , LKML , Pavel Machek References: <200608021842.21774.rjw@sisk.pl> <200608021848.54374.rjw@sisk.pl> <1154548279.7232.34.camel@localhost.localdomain> In-Reply-To: <1154548279.7232.34.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Content-Disposition: inline Message-Id: <200608022212.48293.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 02 August 2006 21:51, Dave Hansen wrote: > On Wed, 2006-08-02 at 18:48 +0200, Rafael J. Wysocki wrote: > > + max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; > > + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { > > + struct page *page = pfn_to_page(pfn); > > + > > + if (!PageNosave(page)) > > + ClearPageNosaveFree(page); > > + } > > This is certainly not the only place in swsusp where there is a bug like > this, Well, I don't think so. They have been hunted for and dealt whith, except for this one. ;-) > but it is not correct to assume that each page inside of a zone is > valid. Obviously, I just forgot about it. --- Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing PageNosaveFree for PageNosave pages.  This allows us to get rid of an ugly hack in kernel/power/snapshot.c#copy_data_pages(). Additionally, the page-copying loop in copy_data_pages() is moved to an inline function. Signed-off-by: Rafael J. Wysocki --- kernel/power/snapshot.c | 27 +++++++++++++-------------- mm/page_alloc.c | 24 ++++++++++++++++-------- 2 files changed, 29 insertions(+), 22 deletions(-) Index: linux-2.6.18-rc2-mm1/mm/page_alloc.c =================================================================== --- linux-2.6.18-rc2-mm1.orig/mm/page_alloc.c +++ linux-2.6.18-rc2-mm1/mm/page_alloc.c @@ -703,7 +703,8 @@ static void __drain_pages(unsigned int c void mark_free_pages(struct zone *zone) { - unsigned long zone_pfn, flags; + unsigned long pfn, max_zone_pfn; + unsigned long flags; int order; struct list_head *curr; @@ -711,18 +712,25 @@ void mark_free_pages(struct zone *zone) return; spin_lock_irqsave(&zone->lock, flags); - for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) - ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn)); + + max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) + if (pfn_valid(pfn)) { + struct page *page = pfn_to_page(pfn); + + if (!PageNosave(page)) + ClearPageNosaveFree(page); + } for (order = MAX_ORDER - 1; order >= 0; --order) list_for_each(curr, &zone->free_area[order].free_list) { - unsigned long start_pfn, i; + unsigned long i; - start_pfn = page_to_pfn(list_entry(curr, struct page, lru)); + pfn = page_to_pfn(list_entry(curr, struct page, lru)); + for (i = 0; i < (1UL << order); i++) + SetPageNosaveFree(pfn_to_page(pfn + i)); + } - for (i=0; i < (1<lock, flags); } Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c =================================================================== --- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c +++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c @@ -208,37 +208,36 @@ unsigned int count_data_pages(void) return n; } +static inline void copy_data_page(long *dst, long *src) +{ + int n; + + /* copy_page and memcpy are not usable for copying task structs. */ + for (n = PAGE_SIZE / sizeof(long); n; n--) + *dst++ = *src++; +} + static void copy_data_pages(struct pbe *pblist) { struct zone *zone; unsigned long pfn, max_zone_pfn; - struct pbe *pbe, *p; + struct pbe *pbe; pbe = pblist; for_each_zone (zone) { if (is_highmem(zone)) continue; mark_free_pages(zone); - /* This is necessary for swsusp_free() */ - for_each_pb_page (p, pblist) - SetPageNosaveFree(virt_to_page(p)); - for_each_pbe (p, pblist) - SetPageNosaveFree(virt_to_page(p->address)); max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { struct page *page = saveable_page(pfn); if (page) { - long *src, *dst; - int n; + void *ptr = page_address(page);; BUG_ON(!pbe); - pbe->orig_address = (unsigned long)page_address(page); - /* copy_page and memcpy are not usable for copying task structs. */ - dst = (long *)pbe->address; - src = (long *)pbe->orig_address; - for (n = PAGE_SIZE / sizeof(long); n; n--) - *dst++ = *src++; + copy_data_page((void *)pbe->address, ptr); + pbe->orig_address = (unsigned long)ptr; pbe = pbe->next; } }