On 08/13/2012 01:16 PM, Gleb Natapov wrote: > On Mon, Aug 13, 2012 at 01:12:46PM +0300, Michael S. Tsirkin wrote: >> On Mon, Aug 13, 2012 at 12:36:41PM +0300, Avi Kivity wrote: >> > On 08/13/2012 12:16 PM, 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. >> > >> > We can have a small rcu-managed hash table to look those up. >> >> Yes but how small? We probably need at least one entry >> per vcpu, no? >> > One entry? We will spend more time managing it than injecting interrupts > :) ideally we need entry for each IPI sent and for each potential MSI > from userspace. What happens when hash table is full? Drop the entire cache. > We stop caching or > invalidate old entries? If later then cache can go valid->invalid which > may complicate the code. > We can drop the entire cache via rcu freeing. In fact we can have a closed hash allocated as a single blob, easy to manage. -- 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
