Re: [PATCH] mm, vmstat: make quiet_vmstat lighter (was: Re: fast path cycle muncher (vmstat: make vmstat_updater deferrable) again and shut down on idle)

[Christoph Lameter]

On Thu, 28 Jan 2016, Michal Hocko wrote:

> > You can drop the need_update check. refresh_cpu_vm_stats() does the same
> > checks in a more efficient way. If you keep this the checks will
> > performed twice.
>
> refresh_cpu_vm_stats does this_cpu_xchg for each counter. Is it really
> more effective than memchr_inv?

Ok makes sense.

Acked-by: Christoph Lameter <cl@xxxxxxxxx>