From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757660AbYGGS0D (ORCPT ); Mon, 7 Jul 2008 14:26:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754883AbYGGSZx (ORCPT ); Mon, 7 Jul 2008 14:25:53 -0400 Received: from mtagate4.uk.ibm.com ([195.212.29.137]:53369 "EHLO mtagate4.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754878AbYGGSZw (ORCPT ); Mon, 7 Jul 2008 14:25:52 -0400 Subject: [PATCH] Make CONFIG_MIGRATION available for s390 From: Gerald Schaefer To: Christoph Lameter , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, KAMEZAWA Hiroyuki , Yasunori Goto , Dave Hansen , Andy Whitcroft In-Reply-To: <48725480.1060808@linux-foundation.org> References: <1215354957.9842.19.camel@localhost.localdomain> <4872319B.9040809@linux-foundation.org> <1215451689.8431.80.camel@localhost.localdomain> <48725480.1060808@linux-foundation.org> Content-Type: text/plain Date: Mon, 07 Jul 2008 20:25:48 +0200 Message-Id: <1215455148.8431.108.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-8.el5_2.2) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2008-07-07 at 12:38 -0500, Christoph Lameter wrote: > How does the compile break? It may be better to fix this where the function > is used. Good point, I did not look into this deep enough and tried to fix the symptoms instead of the cause. There are two locations where the compile breaks: - mm/migrate.c: migrate_vmas() does not know vm_ops->migrate() - inlcude/linux/migrate.h: vma_migratable() does not know policy_zone Both functions are called from mm/mempolicy.c, which is NUMA-only. vma_migratable() is also called from mm/migrate.c, but just inside a '#ifdef CONFIG_NUMA' section. So I think it should be safe to just put the definition of those two functions within '#ifdef CONFIG_NUMA', and the compile error will be gone, see new patch below. Thanks, Gerald --- Subject: [PATCH] Make CONFIG_MIGRATION available for s390 From: Gerald Schaefer We'd like to support CONFIG_MEMORY_HOTREMOVE on s390, which depends on CONFIG_MIGRATION. So far, CONFIG_MIGRATION is only available with NUMA support. This patch makes CONFIG_MIGRATION selectable for architectures that define ARCH_ENABLE_MEMORY_HOTREMOVE. When MIGRATION is enabled w/o NUMA, the kernel won't compile because migrate_vmas() does not know about vm_ops->migrate() and vma_migratable() does not know about policy_zone. To avoid this, those two functions can be restricted to "#ifdef CONFIG_NUMA" because they are not being used w/o NUMA. Signed-off-by: Gerald Schaefer --- include/linux/migrate.h | 2 ++ mm/Kconfig | 2 +- mm/migrate.c | 2 +- 3 files changed, 4 insertions(+), 2 deletions(-) Index: linux-2.6/mm/Kconfig =================================================================== --- linux-2.6.orig/mm/Kconfig +++ linux-2.6/mm/Kconfig @@ -174,7 +174,7 @@ config SPLIT_PTLOCK_CPUS config MIGRATION bool "Page migration" def_bool y - depends on NUMA + depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE help Allows the migration of the physical location of pages of processes while the virtual addresses are not changed. This is useful for Index: linux-2.6/include/linux/migrate.h =================================================================== --- linux-2.6.orig/include/linux/migrate.h +++ linux-2.6/include/linux/migrate.h @@ -8,6 +8,7 @@ typedef struct page *new_page_t(struct page *, unsigned long private, int **); #ifdef CONFIG_MIGRATION +#ifdef CONFIG_NUMA /* Check if a vma is migratable */ static inline int vma_migratable(struct vm_area_struct *vma) { @@ -24,6 +25,7 @@ static inline int vma_migratable(struct return 0; return 1; } +#endif /* CONFIG_NUMA */ extern int isolate_lru_page(struct page *p, struct list_head *pagelist); extern int putback_lru_pages(struct list_head *l); Index: linux-2.6/mm/migrate.c =================================================================== --- linux-2.6.orig/mm/migrate.c +++ linux-2.6/mm/migrate.c @@ -1070,7 +1070,6 @@ out2: mmput(mm); return err; } -#endif /* * Call migration functions in the vma_ops that may prepare @@ -1092,3 +1091,4 @@ int migrate_vmas(struct mm_struct *mm, c } return err; } +#endif