On Mon, Aug 13, 2012 at 12:36:27PM +0300, Gleb Natapov wrote: > On Mon, Aug 13, 2012 at 12:34:32PM +0300, Michael S. Tsirkin wrote: > > On Mon, Aug 13, 2012 at 12:16:46PM +0300, Gleb Natapov wrote: > > > Here is a quick prototype of what we discussed yesterday. This one > > > caches only MSI interrupts for now. The obvious problem is that not > > > all interrupts (namely IPIs and MSIs using KVM_CAP_SIGNAL_MSI) use irq > > > routing table, so they cannot be cached. > > > > I thought this means ID changes need to replace the routing table, no? > > > Correct. This is missing from the patches, but as I said this is just > prototype to see if it is feasible. > What this prototype shows is that we > have problems with IPIs and MSIs from userspace.
I think it's a worthwhile optimization all the same. When you feel it's ready, I'm willing to test to see if it helps vhost. > > > > > > Gleb Natapov (2): > > > Call irq_rt callback under rcu_read_lock() > > > Cache msi irq destination. > > > > > > arch/x86/kvm/lapic.c | 2 +- > > > include/linux/kvm_host.h | 1 + > > > virt/kvm/ioapic.c | 2 +- > > > virt/kvm/ioapic.h | 3 ++- > > > virt/kvm/irq_comm.c | 37 ++++++++++++++++++++----------------- > > > 5 files changed, 25 insertions(+), 20 deletions(-) > > > > > > -- > > > 1.7.10.4 > > -- > Gleb. -- 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
