mm: make CONFIG_MIGRATION available w/o CONFIG_NUMA

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 fix this, those two functions can be restricted to '#ifdef CONFIG_NUMA'
because they are not being used w/o NUMA.  vma_migratable() is moved over
from migrate.h to mempolicy.h.

[kosaki.motohiro@jp.fujitsu.com: build fix]
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: KOSAKI Motorhiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Gerald Schaefer 2008-07-23 21:28:22 -07:00 committed by Linus Torvalds
parent 9ca908f47b
commit 83d1674a94
4 changed files with 21 additions and 23 deletions

View file

@ -3,28 +3,10 @@
#include <linux/mm.h>
#include <linux/mempolicy.h>
#include <linux/pagemap.h>
typedef struct page *new_page_t(struct page *, unsigned long private, int **);
#ifdef CONFIG_MIGRATION
/* Check if a vma is migratable */
static inline int vma_migratable(struct vm_area_struct *vma)
{
if (vma->vm_flags & (VM_IO|VM_HUGETLB|VM_PFNMAP|VM_RESERVED))
return 0;
/*
* Migration allocates pages in the highest zone. If we cannot
* do so then migration (at least from node to node) is not
* possible.
*/
if (vma->vm_file &&
gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping))
< policy_zone)
return 0;
return 1;
}
extern int isolate_lru_page(struct page *p, struct list_head *pagelist);
extern int putback_lru_pages(struct list_head *l);
extern int migrate_page(struct address_space *,
@ -39,9 +21,6 @@ extern int migrate_vmas(struct mm_struct *mm,
const nodemask_t *from, const nodemask_t *to,
unsigned long flags);
#else
static inline int vma_migratable(struct vm_area_struct *vma)
{ return 0; }
static inline int isolate_lru_page(struct page *p, struct list_head *list)
{ return -ENOSYS; }
static inline int putback_lru_pages(struct list_head *l) { return 0; }