Marcelo Tosatti wrote on 2013-01-09: > On Wed, Jan 09, 2013 at 08:07:31AM +0000, Zhang, Yang Z wrote: >>>> if(check_request(KVM_REQ_, ....)) { >>>> ioapic_lock(); (*) >>>> update local EOI exit bitmap from IOAPIC >> In my patch, it traverses IOAPIC entry once and only updates target >> vcpus's eoi exit bitmap. Then make request for all vcpus. With your >> suggestion , all vcpus will traverse all IOAPIC entries. Though ioapic > entry write is rare, it's still not reasonable. > > It should be fast, and very rare (as in once during system > initialization, or device hotplug). Ok. Will revise the patch follow your suggestion. > > Is there a particular case that makes it necessary to optimize scanning? No. >> >>>> ioapic_unlock(); >>>> } >>>> >>> Fine by me. Looks simpler. >>> >>>> >>>> >>>> (*) plus any other lock that paths that update the map take >>>> >>>> >>>> >>>> >>>> >>>>> >>>>> Best regards, >>>>> Yang >>> >>> -- >>> Gleb. >> >> >> Best regards, >> Yang Best regards, Yang -- 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