On Fri, 6 Dec 2013, Joonsoo Kim wrote: > migrate_pages() should return number of pages not migrated or error code. > When unmap_and_move return -EAGAIN, outer loop is re-execution without > initialising nr_failed. This makes nr_failed over-counted. > > So this patch correct it by initialising nr_failed in outer loop. Well nr_retry is the total number of attempts that got EGAIN. nr_failed is the total number of failed attempts. You are making nr_failed the number of pages of the list that have failed to migrated. That syncs with the description. > diff --git a/mm/migrate.c b/mm/migrate.c > index 3747fcd..1f59ccc 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1102,6 +1102,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, > > for(pass = 0; pass < 10 && retry; pass++) { > retry = 0; > + nr_failed = 0; The initialization of nr_failed and retry earlier is then useless. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>