On Wed, 12 Oct 2016, Wanpeng Li wrote: > irq_enter() which is called in scheduler_ipi() is too late to tell RCU > susbstems to end the extended quiescent state before ack_APIC_irq(), > any ideas?
You can call irq_enter/exit() in __smp_reschedule_interrupt(). It can be called nested. Thanks, tglx