Hi Marc,
> this series for the mcp251xfd adds IRQ coalescing support.
>
Thanks for these patches, the performance gains with activated coalescing look awesome!
Testing on a Pi4 mostly 1 channel RX-only Full busload scenarios I see significantly reduced CPU utilization. This is both for CAN 2.0 and CAN-FD use-cases.
I tested this patch series against 5.17 mainline and I think the performance when NOT using coalescing regressed slightly ("measured" via sar -u 1, not sure if that is a valid benchmark?)
I had both driver versions configured for the same fifo sizes and coalescing turned off. The mainline driver actually generates slighty more SPI interrupts in this scenario (20k CAN 2.0 Frames RXed in CAN-FD mode). Not really sure what causes the higher CPU utilization or if it's even relevant (maybe on smaller systems than a Pi4)
Best Regards,
Thomas
