From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754973Ab0GITMb (ORCPT ); Fri, 9 Jul 2010 15:12:31 -0400 Received: from nlpi157.sbcis.sbc.com ([207.115.36.171]:34392 "EHLO nlpi157.prodigy.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754799Ab0GITMZ (ORCPT ); Fri, 9 Jul 2010 15:12:25 -0400 Message-Id: <20100709190900.425400590@quilx.com> User-Agent: quilt/0.48-1 Date: Fri, 09 Jul 2010 14:07:24 -0500 From: Christoph Lameter To: Pekka Enberg Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Cc: Nick Piggin Cc: David Rientjes Subject: [S+Q2 18/19] SLUB: Remove MAX_OBJS limitation References: <20100709190706.938177313@quilx.com> Content-Disposition: inline; filename=sled_unlimited_objects Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is no need anymore for the "inuse" field in the page struct. Extend the objects field to 32 bit allowing a practically unlimited number of objects. Signed-off-by: Christoph Lameter --- include/linux/mm_types.h | 5 +---- mm/slub.c | 7 ------- 2 files changed, 1 insertion(+), 11 deletions(-) Index: linux-2.6/include/linux/mm_types.h =================================================================== --- linux-2.6.orig/include/linux/mm_types.h 2010-07-07 10:54:05.000000000 -0500 +++ linux-2.6/include/linux/mm_types.h 2010-07-07 10:54:36.000000000 -0500 @@ -40,10 +40,7 @@ struct page { * to show when page is mapped * & limit reverse map searches. */ - struct { /* SLUB */ - u16 inuse; - u16 objects; - }; + u32 objects; /* SLUB */ }; union { struct { Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c 2010-07-07 10:54:33.000000000 -0500 +++ linux-2.6/mm/slub.c 2010-07-07 10:54:36.000000000 -0500 @@ -145,7 +145,6 @@ static inline int kmem_cache_debug(struc #define OO_SHIFT 16 #define OO_MASK ((1 << OO_SHIFT) - 1) -#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */ /* Internal SLUB flags */ #define __OBJECT_POISON 0x80000000UL /* Poison object */ @@ -768,9 +767,6 @@ static int verify_slab(struct kmem_cache max_objects = ((void *)page->freelist - start) / s->size; } - if (max_objects > MAX_OBJS_PER_PAGE) - max_objects = MAX_OBJS_PER_PAGE; - if (page->objects != max_objects) { slab_err(s, page, "Wrong number of objects. Found %d but " "should be %d", page->objects, max_objects); @@ -1984,9 +1980,6 @@ static inline int slab_order(int size, i int rem; int min_order = slub_min_order; - if ((PAGE_SIZE << min_order) / size > MAX_OBJS_PER_PAGE) - return get_order(size * MAX_OBJS_PER_PAGE) - 1; - for (order = max(min_order, fls(min_objects * size - 1) - PAGE_SHIFT); order <= max_order; order++) {