On Thu, Nov 26, 2020 at 06:18:33PM +0000, Valentin Schneider wrote: > If I got the RCU bits right from what Thomas mentioned in > > https://lore.kernel.org/r/[email protected] > https://lore.kernel.org/r/[email protected] > > then we're still missing something to notify RCU in the case the IRQ hits > the idle task. All I see on our entry path is > > trace_hardirqs_off(); > ... > irq_handler() > handle_domain_irq(); > ... > trace_hardirqs_on(); > > so we do currently rely on handle_domain_irq()'s irq_enter() + irq_exit() > for that. rcu_irq_enter() says CONFIG_RCU_EQS_DEBUG=y can detect missing > bits, but I don't get any warnings with your series on my Juno.
The scheduler IPI really doesn't need RCU either ;-)
