On Fri, 30 Oct 2020 12:16:00 +0100 Paolo Abeni wrote:
Real-time setups try hard to ensure proper isolation between time critical applications and e.g. network processing performed by the network stack in softirq and RPS is used to move the softirq activity away from the isolated core.
If the network configuration is dynamic, with netns and devices routinely created at run-time, enforcing the correct RPS setting on each newly created device allowing to transient bad configuration became complex.
These series try to address the above, introducing a new sysctl knob: rps_default_mask. The new sysctl entry allows configuring a systemwide RPS mask, to be enforced since receive queue creation time without any fourther per device configuration required.
Additionally, a simple self-test is introduced to check the rps_default_mask behavior.
RPS is disabled by default, the processing is going to happen wherever the IRQ is mapped, and one would hope that the IRQ is not mapped to the core where the critical processing runs.
Would you mind elaborating further on the use case?