> In general yes, but in practice no. We have different paths through which a page
hehe, you said mem_cgroup_per_zone::lru_lock is unnecessary lock.
Also, we can two approach
1. the pages are allowed to exist in different zone of memcg zone and
global zone.
and recover later (by mem_cgroup_isolate_pages).
here is current implementation.
2. the pages aren't allowed to exist in different zone of memcg zone and
global zone.
(you said its mail)
if we select 2, I hope mem_cgroup_move_lists is called by ____pagevec_lru_add
and add_page_to_unevictable_list.
then, page's global lru transition become memcg lru transition automatically.
it increase source code readability.
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