Re: [PATCH v3] mm/damon: Add access checking for hugetlb pages

[Baolin Wang]

Hi SeongJae,

On 12/31/2021 2:19 AM, SeongJae Park wrote:
> On Thu, 30 Dec 2021 16:20:28 +0800 Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> wrote:
>
> > The process's VMAs can be mapped by hugetlb page, but now the DAMON
> > did not implement the access checking for hugetlb pte, so we can not
> > get the actual access count like below if a process VMAs were mapped
> > by hugetlb.
> >
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 4194304-5476352: 0 545
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 140662370467840-140662372970496: 0 545
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 140662372970496-140662375460864: 0 545
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 140662375460864-140662377951232: 0 545
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 140662377951232-140662380449792: 0 545
> > damon_aggregated: target_id=18446614368406014464 nr_regions=12 140662380449792-140662382944256: 0 545
> > ......
> >
> > Thus this patch adds hugetlb access checking support, with this patch
> > we can see below VMA mapped by hugetlb access count.
> >
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296486649856-140296489914368: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296489914368-140296492978176: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296492978176-140296495439872: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296495439872-140296498311168: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296498311168-140296501198848: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296501198848-140296504320000: 1 3
> > damon_aggregated: target_id=18446613056935405824 nr_regions=12 140296504320000-140296507568128: 1 2
> > ......
> >
> > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
>
> In addition to unwrapping program outputs in commit message, I personally
> prefer indenting those with 4 spaces[1], but I wouldn't bother you for such a
> trivial thing.  Thank you for this patch!

I noticed your comments before, but I still think the message line is 
too long to unreadable. Anyway thanks for your reviewing.

> Reviewed-by: SeongJae Park <sj@xxxxxxxxxx>
>
> [1] https://lore.kernel.org/linux-mm/17421c73-2124-63c2-1925-dcea5c976711@xxxxxxxxxxxxxxxx