Re: [PATCH v2] mm/memcontrol: Fix seq_buf size to save memory when PAGE_SIZE is large

From: Muchun Song
Date: Tue Oct 22 2024 - 03:31:16 EST




> On Oct 21, 2024, at 21:00, Ryan Roberts <ryan.roberts@xxxxxxx> wrote:
>
> Previously the seq_buf used for accumulating the memory.stat output was
> sized at PAGE_SIZE. But the amount of output is invariant to PAGE_SIZE;
> If 4K is enough on a 4K page system, then it should also be enough on a
> 64K page system, so we can save 60K on the static buffer used in
> mem_cgroup_print_oom_meminfo(). Let's make it so.
>
> This also has the beneficial side effect of removing a place in the code
> that assumed PAGE_SIZE is a compile-time constant. So this helps our
> quest towards supporting boot-time page size selection.
>
> Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
> Acked-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>
> Acked-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>

Acked-by: Muchun Song <muchun.song@xxxxxxxxx>

Thanks.