memcg: mm_update_next_owner: move for_each_thread() into try_to_set_owner()

mm_update_next_owner() checks the children / real_parent->children to
avoid the "everything else" loop in the likely case, but this won't work
if a child/sibling has a zombie leader with ->mm == NULL.

Move the for_each_thread() logic into try_to_set_owner(), if nothing else
this makes the children/siblings/everything searches more consistent.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Oleg Nesterov <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Jinliang Zheng <[email protected]>
Cc: Mateusz Guzik <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Tycho Andersen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions