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>
diff --git a/mm/migrate.c b/mm/migrate.c
index 939888f..0edeac9 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -147,7 +147,7 @@
static void remove_file_migration_ptes(struct page *old, struct page *new)
{
struct vm_area_struct *vma;
- struct address_space *mapping = page_mapping(new);
+ struct address_space *mapping = new->mapping;
struct prio_tree_iter iter;
pgoff_t pgoff = new->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
@@ -664,13 +664,15 @@
* needs to be effective.
*/
try_to_free_buffers(page);
+ goto rcu_unlock;
}
- goto rcu_unlock;
+ goto skip_unmap;
}
/* Establish migration ptes or remove ptes */
try_to_unmap(page, 1);
+skip_unmap:
if (!page_mapped(page))
rc = move_to_new_page(newpage, page);