On Fri, Jan 12, 2018 at 2:13 AM, Peter Zijlstra <pet...@infradead.org> wrote: > On Fri, Jan 12, 2018 at 06:23:08AM +0100, Mike Galbraith wrote: >> >> How would that be better than what RT used to do, and I still do for my >> RT kernels via boot option, namely split ksoftirqd into per-softirq >> threads. > > Since we mention it; one of the problems RT has is that all RX is > through a single softirq context, which generates a priority inversion > between devices.
Oh, yes, that is complete and utter shit. Not acceptable at all. As mentioned, it really would need to be per-cpu _and_ per-softirq. Which is why I thought workqueues might be the thing. Whatever RT is doing is apparently just pure and utter garbage. Linus