On 07/11/2012 01:18 PM, Jan Kiszka wrote: > On 2012-07-11 11:53, Avi Kivity wrote: >> On 07/03/2012 10:21 PM, Alex Williamson wrote: >>> Here's the latest iteration of adding an interface to assert and >>> de-assert level interrupts from external drivers like vfio. These >>> apply on top of the previous argument cleanup, documentation, and >>> sanitization patches for irqfd. It would be great to get this queued >>> in next for linux 3.6. >>> >>> I believe I've addressed all the previous comments, including fixing >>> the locking problems in eoifd. I've run this with lockdep adding >>> and removing level irqfd/eoifd pairs without any problems. Please >>> let me know if there are any further comments. Thanks, >> >> Is there any performance justification for level irqfd? Don't all >> new/high bandwidth devices support msi, and this is just a legacy path? > > I think we've been there before, but the situation hasn't improved much: > > Apparently, some GPUs still prefer INTx over MSI. Some wireless chipsets > too. I'd appreciate a couple of examples for formality's sake. > And then there is not easily replaceable legacy hardware like old > telephony adapters or industrial I/O cards etc. that want this. I imagine legacy hardware will live with the speed of routing through qemu, when running on modern platforms. -- error compiling committee.c: too many arguments to function -- 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
