Re: [PATCH 1/2] mm/damon/lru_sort: support addr_unit for DAMON_LRU_SORT

[SeongJae Park <sj@kernel.org>]

On Wed, 10 Sep 2025 19:32:20 +0800 Quanmin Yan <yanquanmin1@huawei.com> wrote:

> Implement a sysfs file to expose addr_unit for DAMON_LRU_SORT
> users. During parameter application, use the configured
> addr_unit parameter to perform the necessary initialization.
> Similar to the core layer, prevent setting addr_unit to zero.
> 
> It is worth noting that when monitor_region_start and
> monitor_region_end are unset (i.e., 0), their values will
> later be set to biggest_system_ram. At that point, addr_unit
> may not be the default value 1. Although we could divide the
> biggest_system_ram value by addr_unit, changing addr_unit
> without setting monitor_region_start/end should be considered
> a user misoperation. And biggest_system_ram is only within
> the 0~ULONG_MAX range, system can clearly work correctly with
> addr_unit=1. Therefore, if monitor_region_start/end are unset,
> always silently reset addr_unit to 1.

Sounds fair to me.

> 
> Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>

Reviewed-by: SeongJae Park <sj@kernel.org>


Thanks,
SJ

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