On 4/13/21 10:24 PM, Thomas Gleixner wrote: > On Tue, Apr 13 2021 at 14:16, Cédric Le Goater wrote: >>>> We could test irq_settings_no_debug() directly under handle_nested_irq() >>>> and handle_irq_event_percpu() to avoid calling note_interrupt(), just >>>> like we do for noirqdebug. >>> >>> We can do that, but then we should not just make it: >>> >>> if (!irqnodebug && !irq_settings_no_debug(desc)) >>> note_interrupt(...); >>> >>> Instead have only one condition: >>> >>> if (!irq_settings_no_debug(desc)) >>> note_interrupt(...); >>> >>> See the uncompiled delta patch below. >> >> I merged this second part with the first and gave IRQF_NO_DEBUG a try >> on P8 and P9 systems and all looked fine. I should send both patches >> after IRQF_NO_AUTOEN is merged in mainline. > > Does having that NODEBUG flag set on the IPI irqs make a measurable > difference or is it just too small to matter?
It does not add much benefits on the 2s and 4s systems but I will give it a try on bigger ones when I can grab them. Then we can decide if it is worth merging. Thanks, C.