Re: [PATCH v2 0/4] /proc/stat: Reduce irqs counting performance overhead

[Matthew Wilcox]

On Wed, Jan 09, 2019 at 01:03:33PM -0500, Waiman Long wrote:
> The paragraph above may be a bit misleading. This v2 patch actually
> touches very little on percpu accounting aspect of the IRQ counts. See
> patches 2 and 3 for the relevant changes which is just a few line of new
> codes. Please review the individual patches before Nak'ing.
> 
> I could theoretically generalize them into a new set of percpu counting
> helpers, but the idea behind it is quite different from the use cases of
> percpu counter. So it may not be a good idea of adding it to there.

Did you even try just using the general purpose infrastructure that's
in place?  If that shows a performance problem _then_ it's time to make
this special snowflake just a little more special.  Not before.