On 07/27/2011 04:00 PM, Sasha Levin wrote:
Currently the method of dealing with an IO operation on a bus (PIO/MMIO) is to call the read or write callback for each device registered on the bus until we find a device which handles it. Since the number of devices on a bus can be significant due to ioeventfds and coalesced MMIO zones, this leads to a lot of overhead on each IO operation. Instead of registering devices, we now register ranges which points to a device. Lookup is done using an efficient bsearch instead of a linear search. Performance test was conducted by comparing exit count per second with 200 ioeventfds created on one byte and the guest is trying to access a different byte continuously (triggering usermode exits). Before the patch the guest has achieved 259k exits per second, after the patch the guest does 274k exits per second.
Applied, thanks. -- 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