Re: Sysfs one-value-per-file (was Re: [PATCH] vmstat: don't auto expand the sysfs files)

[Pasha Tatashin]

On Thu, Dec 28, 2023 at 3:43 PM David Rientjes <rientjes@xxxxxxxxxx> wrote:
>
> On Thu, 28 Dec 2023, Pasha Tatashin wrote:
>
> > > > But for existing files and conventions, I think we should settle it as
> > > > "keep doing what you've been doing for 13+ years" and don't force this
> > > > argument every time a kernel developer wants to just add one more stat.
> > >
> > > Absolutely.  Let's do what makes most sense.  For new things, one value
> > > per file.  For stats which logically group with other existing stats,
> > > do whatever the existing other stats are currently doing.
> >
> > The intent of "[PATCH] vmstat: don't auto expand the sysfs files" is
> > to do exactly this: keep the current fields in
> > /sys/devices/system/node/node*/vmstat as-is, but prevent future fields
> > added to node_stat, numa_stat, zone_stat from showing in vmstat.
> >
>
> This is the opposite of what Andrew and I wrote above.  There should be no
> need to start preventing future stats from being grouped together in
> vmstat if it logically makes sense.
>
> NAK.

Hm, I must have misunderstood what Andrew said.

I am ok with this patch being NAK, as long as the IOMMU observability
patch series and Per-Page Metadata patch can be merged upstream, and
extend vmstat without a NAK from GregKH for expanding a sysfs vmstat
file.

Pasha