Re: [RFC 1/2] softirq: Defer net rx/tx processing to ksoftirqd context

From: Linus Torvalds
Date: Thu Jan 11 2018 - 14:43:44 EST


On Thu, Jan 11, 2018 at 11:15 AM, Eric Dumazet <edumazet@xxxxxxxxxx> wrote:
>
> How are we supposed to know this particular workload is problematic
> for innocent user threads on the same cpu ?

Put that question another way: how is the _softirq_ code supposed to know?

If you can't know, then the softirq code definitely can't know either.
It has even less information. It doesn't know about NAPI, it doesn't
know about irq steering, it doesn't know anything at all.

Linus