From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933204Ab1EZSPL (ORCPT ); Thu, 26 May 2011 14:15:11 -0400 Received: from smtp102.prem.mail.ac4.yahoo.com ([76.13.13.41]:32847 "HELO smtp102.prem.mail.ac4.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1757976Ab1EZSPE (ORCPT ); Thu, 26 May 2011 14:15:04 -0400 X-Yahoo-SMTP: _Dag8S.swBC1p4FJKLCXbs8NQzyse1SYSgnAbY0- X-YMail-OSG: Pudt9nMVM1knQRfp8aS4MHv9.F4vJu54COiBQoWvgerFlxN 9ssnGfKc9QEB7KEpkcGSFUfnpqeJxy.iHx2JahKwO6C9Nab_Jx2AuHuaEHvL wvdxv3SLFY_j_RvtBf.jmkVn.ngBztz7KvpZ8DNaYfzvrv5tP55X5k7DT2eD yk3Nrb_1m7IJd8FHtDozQEgewahBJMPgmjnmVEwQpVKPOnJrRTPhvUeNYdEC XuSJ0fjfe4ddfe16yRHXGATwokeCYQ4c0pB2YpndvKwsWfkvSXGSgv4LBEM9 6eGMqHX1E1DN3I5a0MjyOjJ.XvbDpfXyvEDecnQQwUmEftWrf X-Yahoo-Newman-Property: ymail-3 Message-Id: <20110526181502.558602037@linux.com> User-Agent: quilt/0.48-1 Date: Thu, 26 May 2011 13:14:44 -0500 From: Christoph Lameter To: Pekka Enberg Cc: David Rientjes Cc: Eric Dumazet Cc: "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org Cc: Thomas Gleixner Subject: [slubllv6 02/17] slub: Do not use frozen page flag but a bit in the page counters References: <20110526181442.789868308@linux.com> Content-Disposition: inline; filename=frozen_field Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Do not use a page flag for the frozen bit. It needs to be part of the state that is handled with cmpxchg_double(). So use a bit in the counter struct in the page struct for that purpose. Also all page start out as frozen pages so set the bit when the page is allocated. Signed-off-by: Christoph Lameter --- include/linux/mm_types.h | 5 +++-- include/linux/page-flags.h | 2 -- mm/slub.c | 12 ++++++------ 3 files changed, 9 insertions(+), 10 deletions(-) Index: linux-2.6/include/linux/mm_types.h =================================================================== --- linux-2.6.orig/include/linux/mm_types.h 2011-05-19 13:54:29.271151992 -0500 +++ linux-2.6/include/linux/mm_types.h 2011-05-19 13:59:28.551151643 -0500 @@ -41,8 +41,9 @@ struct page { * & limit reverse map searches. */ struct { /* SLUB */ - u16 inuse; - u16 objects; + unsigned inuse:16; + unsigned objects:15; + unsigned frozen:1; }; }; union { Index: linux-2.6/include/linux/page-flags.h =================================================================== --- linux-2.6.orig/include/linux/page-flags.h 2011-05-19 13:54:29.281151992 -0500 +++ linux-2.6/include/linux/page-flags.h 2011-05-19 13:59:28.551151643 -0500 @@ -212,8 +212,6 @@ PAGEFLAG(SwapBacked, swapbacked) __CLEAR __PAGEFLAG(SlobFree, slob_free) -__PAGEFLAG(SlubFrozen, slub_frozen) - /* * Private page markings that may be used by the filesystem that owns the page * for its own purposes. Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c 2011-05-19 13:59:24.981151647 -0500 +++ linux-2.6/mm/slub.c 2011-05-19 13:59:28.561151643 -0500 @@ -166,7 +166,7 @@ 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 */ +#define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */ /* Internal SLUB flags */ #define __OBJECT_POISON 0x80000000UL /* Poison object */ @@ -1025,7 +1025,7 @@ static noinline int free_debug_processin } /* Special debug activities for freeing objects */ - if (!PageSlubFrozen(page) && !page->freelist) + if (!page->frozen && !page->freelist) remove_full(s, page); if (s->flags & SLAB_STORE_USER) set_track(s, object, TRACK_FREE, addr); @@ -1421,7 +1421,7 @@ static inline int lock_and_freeze_slab(s { if (slab_trylock(page)) { __remove_partial(n, page); - __SetPageSlubFrozen(page); + page->frozen = 1; return 1; } return 0; @@ -1535,7 +1535,7 @@ static void unfreeze_slab(struct kmem_ca { struct kmem_cache_node *n = get_node(s, page_to_nid(page)); - __ClearPageSlubFrozen(page); + page->frozen = 0; if (page->inuse) { if (page->freelist) { @@ -1866,7 +1866,7 @@ new_slab: flush_slab(s, c); slab_lock(page); - __SetPageSlubFrozen(page); + page->frozen = 1; c->node = page_to_nid(page); c->page = page; goto load_freelist; @@ -2048,7 +2048,7 @@ static void __slab_free(struct kmem_cach page->freelist = object; page->inuse--; - if (unlikely(PageSlubFrozen(page))) { + if (unlikely(page->frozen)) { stat(s, FREE_FROZEN); goto out_unlock; }