Re: [PATCH net-next v10] net: reduce ARFS flow updates by checking LLC affinity

[chuang]

On Thu, Oct 8, 2026 at 10:14 PM Neal Cardwell <ncardwell@xxxxxxxxxx> wrote:
>
> On Thu, Oct 8, 2026 at 9:33 AM Chuang Wang <nashuiliang@xxxxxxxxx> wrote:
> >
> ...
> > --- a/net/core/sysctl_net_core.c
> > +++ b/net/core/sysctl_net_core.c
> > @@ -560,6 +560,13 @@ static struct ctl_table net_core_table[] = {
> >                 .mode           = 0644,
> >                 .proc_handler   = rps_sock_flow_sysctl
> >         },
> > +       {
> > +               .procname       = "rps_feat_llc_affinity",
> > +               .data           = &rps_feat_llc_affinity.key,
> > +               .maxlen         = sizeof(rps_feat_llc_affinity.key),
> > +               .mode           = 0644,
> > +               .proc_handler   = proc_do_static_key
> > +       },
>
> Having "feat_" in the name of a sysctl seems redundant, since most
> sysctls are features.
>
> Also, the name seems overly broad, as it could also apply to other
> RPS/RFS mechanisms leveraging LLC affinity, for which we might want
> separate sysctl control knobs. I'd suggest perhaps something more
> specific, like "rps_llc_affinity_for_set_cpu".

How about arfs_llc_affinity or rfs_accel_llc_affinity or
rfs_accel_llc_affinity_steer?

The knob only gates the aRFS (CONFIG_RFS_ACCEL) hardware steering
update in set_rps_cpu(), so scoping the name to aRFS describes exactly
what it controls.

>
> neal