Re: [PATCH] mm: remove '!root_reclaim' checking in should_abort_scan()

[T.J. Mercier]

On Wed, Feb 11, 2026 at 7:22 PM zhaoyang.huang
<zhaoyang.huang@xxxxxxxxxx> wrote:
>
> From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>
>
> Nowadays, ANDROID system replaces madivse with memory.reclaim to implement
> user space memory management which desires to reclaim a certain amount of
> memcg's memory. However, oversized reclaiming and high latency are observed
> as there is no limitation over nr_reclaimed inside try_to_shrink_lruvec
> when MGLRU enabled. Besides, this could also affect all none root_reclaim
> such as reclaim_high etc.
> Since the commit 'b82b530740b9' ("mm: vmscan: restore incremental cgroup
> iteration") introduces sc->memcg_full_walk to limit the walk range of
> mem_cgroup_iter and keep the fairness among the descendants of one memcg.
> This commit would like to make single memcg's scanning more precised by
> removing the criteria of 'if (!root_reclaim)' inside
> should_abort_scan().
>
> Suggested-by: T.J.Mercier <tjmercier@xxxxxxxxxx>
> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>

Reviewed-by: T.J. Mercier <tjmercier@xxxxxxxxxx>

Thanks!