Re: [PATCH -mm -v3 1/6] mm, swap: Add swap cache statistics sysfs interface

[Huang\, Ying]

Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> writes:

> On Tue, 25 Jul 2017 09:51:46 +0800 "Huang, Ying" <ying.huang@xxxxxxxxx> wrote:
>
>> The swap cache stats could be gotten only via sysrq, which isn't
>> convenient in some situation.  So the sysfs interface of swap cache
>> stats is added for that.  The added sysfs directories/files are as
>> follow,
>> 
>> /sys/kernel/mm/swap
>> /sys/kernel/mm/swap/cache_find_total
>> /sys/kernel/mm/swap/cache_find_success
>> /sys/kernel/mm/swap/cache_add
>> /sys/kernel/mm/swap/cache_del
>> /sys/kernel/mm/swap/cache_pages
>
> We should document this somewhere.  Documentation/ABI/ is the formal
> place for sysfs files, but nobody will think to look there for VM
> things, so perhaps place a pointer to the Documentation/ABI/ files
> within Documentation/vm somewhere, only there isn't an appropriate
> Documentation/vm file ;)
>
> Or just put all these things in debugfs.  These are pretty specialized
> things and appear to be developer-only files of short-term interest?

Yes.  Debugfs should be better place for these.  Will update it in the
next version.

And I also introduced sysfs interface in [2/6] and [5/6]

/sys/kernel/mm/swap/ra_hits
/sys/kernel/mm/swap/ra_total

/sys/kernel/mm/swap/vma_ra_enabled
/sys/kernel/mm/swap/vma_ra_max_order

Will add ABI document for them.

Best Regards,
Huang, Ying