Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753313AbcDLEvh (ORCPT ); Tue, 12 Apr 2016 00:51:37 -0400 Received: from mail-pf0-f177.google.com ([209.85.192.177]:32892 "EHLO mail-pf0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752558AbcDLEvf (ORCPT ); Tue, 12 Apr 2016 00:51:35 -0400 From: js1304@gmail.com X-Google-Original-From: iamjoonsoo.kim@lge.com To: Andrew Morton Cc: Christoph Lameter , Pekka Enberg , David Rientjes , Jesper Dangaard Brouer , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim Subject: [PATCH v2 02/11] mm/slab: remove BAD_ALIEN_MAGIC again Date: Tue, 12 Apr 2016 13:50:57 +0900 Message-Id: <1460436666-20462-3-git-send-email-iamjoonsoo.kim@lge.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1460436666-20462-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1460436666-20462-1-git-send-email-iamjoonsoo.kim@lge.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1697 Lines: 50 From: Joonsoo Kim Initial attemp to remove BAD_ALIEN_MAGIC is once reverted by 'commit edcad2509550 ("Revert "slab: remove BAD_ALIEN_MAGIC"")' because it causes a problem on m68k which has many node but !CONFIG_NUMA. In this case, although alien cache isn't used at all but to cope with some initialization path, garbage value is used and that is BAD_ALIEN_MAGIC. Now, this patch set use_alien_caches to 0 when !CONFIG_NUMA, there is no initialization path problem so we don't need BAD_ALIEN_MAGIC at all. So remove it. Tested-by: Geert Uytterhoeven Signed-off-by: Joonsoo Kim --- mm/slab.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index d8746c0..373b8be 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -421,8 +421,6 @@ static struct kmem_cache kmem_cache_boot = { .name = "kmem_cache", }; -#define BAD_ALIEN_MAGIC 0x01020304ul - static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) @@ -637,7 +635,7 @@ static int transfer_objects(struct array_cache *to, static inline struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) { - return (struct alien_cache **)BAD_ALIEN_MAGIC; + return NULL; } static inline void free_alien_cache(struct alien_cache **ac_ptr) @@ -1205,7 +1203,7 @@ void __init kmem_cache_init(void) sizeof(struct rcu_head)); kmem_cache = &kmem_cache_boot; - if (num_possible_nodes() == 1) + if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) use_alien_caches = 0; for (i = 0; i < NUM_INIT_LISTS; i++) -- 1.9.1