From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx134.postini.com [74.125.245.134]) by kanga.kvack.org (Postfix) with SMTP id 0D2896B0089 for ; Thu, 21 Jun 2012 04:04:58 -0400 (EDT) Received: by dakp5 with SMTP id p5so654307dak.14 for ; Thu, 21 Jun 2012 01:04:58 -0700 (PDT) Date: Thu, 21 Jun 2012 01:04:55 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH 4/4] don't do __ClearPageSlab before freeing slab page. In-Reply-To: <1340225959-1966-5-git-send-email-glommer@parallels.com> Message-ID: References: <1340225959-1966-1-git-send-email-glommer@parallels.com> <1340225959-1966-5-git-send-email-glommer@parallels.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: Pekka Enberg , linux-mm@kvack.org, Cristoph Lameter , Pekka Enberg , Michal Hocko , Kamezawa Hiroyuki , Johannes Weiner , Suleiman Souhlal On Thu, 21 Jun 2012, Glauber Costa wrote: > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 6092f33..fdec73e 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -698,8 +698,10 @@ static bool free_pages_prepare(struct page *page, unsigned int order) > > if (PageAnon(page)) > page->mapping = NULL; > - for (i = 0; i < (1 << order); i++) > + for (i = 0; i < (1 << order); i++) { > + __ClearPageSlab(page + i); > bad += free_pages_check(page + i); > + } > if (bad) > return false; > > @@ -2561,6 +2563,7 @@ EXPORT_SYMBOL(get_zeroed_page); > void __free_pages(struct page *page, unsigned int order) > { > if (put_page_testzero(page)) { > + __ClearPageSlab(page); > if (order == 0) > free_hot_cold_page(page, 0); > else These are called from a number of different places that has nothing to do with slab so it's certainly out of place here. Is there really no alternative way of doing this? > diff --git a/mm/slab.c b/mm/slab.c > index cb6da05..3e578fc 100644 > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -1821,11 +1821,6 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr) > else > sub_zone_page_state(page_zone(page), > NR_SLAB_UNRECLAIMABLE, nr_freed); > - while (i--) { > - BUG_ON(!PageSlab(page)); > - __ClearPageSlab(page); > - page++; > - } > if (current->reclaim_state) > current->reclaim_state->reclaimed_slab += nr_freed; > free_pages((unsigned long)addr, cachep->gfporder); And we lose this validation in slab. I'm hoping there's an alternative. -- 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