Am 18.09.2015 um 13:29 schrieb Paolo Bonzini: > > > On 18/09/2015 12:54, Christian Borntraeger wrote: >>> -/* halt polling only reduces halt latency by 5-7 us, 500us is enough */ >>> -static unsigned int halt_poll_ns = 500000; >>> +/* Architectures should define their poll value according to the halt latency */ >>> +static unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT; >> >> Yes, I prefer this over disabling it via Kconfig. There are benchmarks which >> benefit from polling on s390. Furthermore it seems that the latency >> strongly depends on timing of the architecture so making it per arch is >> probably the right thing to do. > > Perhaps a #ifndef is better than replicating the 500us default in all > architectures? Or should the default be 0? I prefer to not have an ifdef in .c files. I would assume that over time architectures will provide their own number, e.g. for my uperf cases that got better, 50000 was enough. 500000 just increased cpu overhead. Christian -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html