2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-29 07:34:06 +08:00
linux-next/include/linux/page-isolation.h
Minchan Kim 435b405c06 memory-hotplug: fix pages missed by race rather than failing
If race between allocation and isolation in memory-hotplug offline
happens, some pages could be in MIGRATE_MOVABLE of free_list although the
pageblock's migratetype of the page is MIGRATE_ISOLATE.

The race could be detected by get_freepage_migratetype in
__test_page_isolated_in_pageblock.  If it is detected, now EBUSY gets
bubbled all the way up and the hotplug operations fails.

But better idea is instead of returning and failing memory-hotremove, move
the free page to the correct list at the time it is detected.  It could
enhance memory-hotremove operation success ratio although the race is
really rare.

Suggested by Mel Gorman.

[akpm@linux-foundation.org: small cleanup]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:46 +09:00

47 lines
1.3 KiB
C

#ifndef __LINUX_PAGEISOLATION_H
#define __LINUX_PAGEISOLATION_H
bool has_unmovable_pages(struct zone *zone, struct page *page, int count);
void set_pageblock_migratetype(struct page *page, int migratetype);
int move_freepages_block(struct zone *zone, struct page *page,
int migratetype);
int move_freepages(struct zone *zone,
struct page *start_page, struct page *end_page,
int migratetype);
/*
* Changes migrate type in [start_pfn, end_pfn) to be MIGRATE_ISOLATE.
* If specified range includes migrate types other than MOVABLE or CMA,
* this will fail with -EBUSY.
*
* For isolating all pages in the range finally, the caller have to
* free all pages in the range. test_page_isolated() can be used for
* test it.
*/
int
start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype);
/*
* Changes MIGRATE_ISOLATE to MIGRATE_MOVABLE.
* target range is [start_pfn, end_pfn)
*/
int
undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype);
/*
* Test all pages in [start_pfn, end_pfn) are isolated or not.
*/
int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn);
/*
* Internal functions. Changes pageblock's migrate type.
*/
int set_migratetype_isolate(struct page *page);
void unset_migratetype_isolate(struct page *page, unsigned migratetype);
#endif