On Wed, Jul 24, 2024 at 07:02:12PM +0000, Kinsey Ho wrote: > The generation number in struct mem_cgroup_reclaim_iter should be > incremented on every round-trip. Currently, it is possible for a > concurrent reclaimer to jump in at the end of the hierarchy, causing a > traversal restart (resetting the iteration position) without > incrementing the generation number. > > Move the traversal restart such that the generation number is > incremented before the restart. > > Signed-off-by: Kinsey Ho <kinseyho@xxxxxxxxxx> The consequence of resetting the position without bumping the generation would be that another ongoing mem_cgroup_iter() could walk the tree twice, which is undesirable. It would be good to spell that out in the changelog. Otherwise, looks good to me. Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
