From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Subject: mm/migrate.c: check pagelist in move_pages_and_store_status() When pagelist is empty, it is not necessary to do the move and store. Also it consolidate the empty list check in one place. Link: http://lkml.kernel.org/r/20200214003017.25558-4-richardw.yang@xxxxxxxxxxxxxxx Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/migrate.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) --- a/mm/migrate.c~mm-migratec-check-pagelist-in-move_pages_and_store_status +++ a/mm/migrate.c @@ -1518,9 +1518,6 @@ static int do_move_pages_to_node(struct { int err; - if (list_empty(pagelist)) - return 0; - err = migrate_pages(pagelist, alloc_new_node_page, NULL, node, MIGRATE_SYNC, MR_SYSCALL); if (err) @@ -1608,6 +1605,9 @@ static int move_pages_and_store_status(s { int err; + if (list_empty(pagelist)) + return 0; + err = do_move_pages_to_node(mm, pagelist, node); if (err) { /* @@ -1705,9 +1705,6 @@ static int do_pages_move(struct mm_struc current_node = NUMA_NO_NODE; } out_flush: - if (list_empty(&pagelist)) - return err; - /* Make sure we do not overwrite the existing error */ err1 = move_pages_and_store_status(mm, current_node, &pagelist, status, start, i, nr_pages); _
