On 02/15/2019 02:46 AM, Yu Zhao wrote:
> Switch from per mm_struct to per pmd page table lock by enabling
> ARCH_ENABLE_SPLIT_PMD_PTLOCK. This provides better granularity for
> large system.
>
> I'm not sure if there is contention on mm->page_table_lock. Given
> the option comes at no cost (apart from initializing more spin
> locks), why not enable it now.
>
This has similar changes to what I had posted part of the general page table
page accounting clean up series on arm64 last month.
https://www.spinics.net/lists/arm-kernel/msg701954.html