Michal Hocko <[email protected]> wrote: > On Thu 17-09-20 06:59:00, Miaohe Lin wrote: >> Since commit 79dfdaccd1d5 ("memcg: make oom_lock 0 and 1 based rather >> than counter"), the mem_cgroup_unmark_under_oom() is added and the >> comment of the mem_cgroup_oom_unlock() is moved here. But this comment >> make no sense here because mem_cgroup_oom_lock() does not operate on >> under_oom field. > >OK, so I've looked into this more deeply and I finally remember why we have >this comment here. The point is that under_oom shouldn't underflow and that we >have to explicitly check for > 0 because a new child memcg could have been >added between mem_cgroup_mark_under_oom and mem_cgroup_unmark_under_oom. > >So the comment makes sense although it is not as helpful as it could be. >I think that changing it to the following will be more usefule > > /* > * Be careful about under_oom underflows becase a child memcg > * could have neem added after mem_cgroup_mark_under_oom
Should it be s/neem/been/ ? > */ Many thanks for detailed explanation. Will fix it in v2. Thanks again.
