From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Subject: mm/migrate.c: wrap do_move_pages_to_node() and store_status() Usually, do_move_pages_to_node() and store_status() are used in combination. We have three similar call sites. Let's provide a wrapper for both function calls - move_pages_and_store_status - to make the calling code easier to maintain and fix (as noted by Yang Shi, the return value handling of do_move_pages_to_node() has a flaw). [david@xxxxxxxxxx rephrase changelog] Link: http://lkml.kernel.org/r/20200214003017.25558-3-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 | 61 +++++++++++++++++++++++-------------------------- 1 file changed, 29 insertions(+), 32 deletions(-) --- a/mm/migrate.c~mm-migratec-wrap-do_move_pages_to_node-and-store_status +++ a/mm/migrate.c @@ -1602,6 +1602,29 @@ out: return err; } +static int move_pages_and_store_status(struct mm_struct *mm, int node, + struct list_head *pagelist, int __user *status, + int start, int i, unsigned long nr_pages) +{ + int err; + + err = do_move_pages_to_node(mm, pagelist, node); + if (err) { + /* + * Positive err means the number of failed + * pages to migrate. Since we are going to + * abort and return the number of non-migrated + * pages, so need to incude the rest of the + * nr_pages that have not been attempted as + * well. + */ + if (err > 0) + err += nr_pages - i - 1; + return err; + } + return store_status(status, start, node, i - start); +} + /* * Migrate an array of page address onto an array of nodes and fill * the corresponding array of status. @@ -1645,21 +1668,8 @@ static int do_pages_move(struct mm_struc current_node = node; start = i; } else if (node != current_node) { - err = do_move_pages_to_node(mm, &pagelist, current_node); - if (err) { - /* - * Positive err means the number of failed - * pages to migrate. Since we are going to - * abort and return the number of non-migrated - * pages, so need to incude the rest of the - * nr_pages that have not been attempted as - * well. - */ - if (err > 0) - err += nr_pages - i - 1; - goto out; - } - err = store_status(status, start, current_node, i - start); + err = move_pages_and_store_status(mm, current_node, + &pagelist, status, start, i, nr_pages); if (err) goto out; start = i; @@ -1688,13 +1698,8 @@ static int do_pages_move(struct mm_struc if (err) goto out_flush; - err = do_move_pages_to_node(mm, &pagelist, current_node); - if (err) { - if (err > 0) - err += nr_pages - i - 1; - goto out; - } - err = store_status(status, start, current_node, i - start); + err = move_pages_and_store_status(mm, current_node, &pagelist, + status, start, i, nr_pages); if (err) goto out; current_node = NUMA_NO_NODE; @@ -1704,16 +1709,8 @@ out_flush: return err; /* Make sure we do not overwrite the existing error */ - err1 = do_move_pages_to_node(mm, &pagelist, current_node); - /* - * Don't have to report non-attempted pages here since: - * - If the above loop is done gracefully all pages have been - * attempted. - * - If the above loop is aborted it means a fatal error - * happened, should return ret. - */ - if (!err1) - err1 = store_status(status, start, current_node, i - start); + err1 = move_pages_and_store_status(mm, current_node, &pagelist, + status, start, i, nr_pages); if (err >= 0) err = err1; out: _
