memory hotplug: migrate swap cache page
authorShaohua Li <shaohua.li@intel.com>
Tue, 22 Sep 2009 00:01:19 +0000 (17:01 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 22 Sep 2009 14:17:26 +0000 (07:17 -0700)
commitabfc3488118d48a2b8cce5a2345901aac6b03fee
tree37e39eeef9cb43716339315833be3592b01f9a64
parentf52407ce2deac76c87abc8211a63ea152ba72d54
memory hotplug: migrate swap cache page

In test, some pages in swap-cache can't be migrated, as they aren't rmap.

unmap_and_move() ignores swap-cache page which is just read in and hasn't
rmap (see the comments in the code), but swap_aops provides .migratepage.
Better to migrate such pages instead of ignore them.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Yakui Zhao <yakui.zhao@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/migrate.c