On Thu, 2015-12-03 at 10:22 -0800, Yunhong Jiang wrote: > When assigning a VFIO device to a KVM guest with low latency requirement, it > is better to handle the interrupt in the hard interrupt context, to reduce > the context switch to/from the IRQ thread. > > Based on discussion on https://lkml.org/lkml/2015/10/26/764, the VFIO msi > interrupt is changed to use request_threaded_irq(). The primary interrupt > handler tries to set the guest interrupt atomically. If it fails to achieve > it, a threaded interrupt handler will be invoked. > > The irq_bypass manager is extended for this purpose. The KVM eventfd will > provide a irqbypass consumer to handle the interrupt at hard interrupt > context. The producer will invoke the consumer's handler then.
Do you have any performance data? Thanks, Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html