Re: [PATCH] kvm: x86: reduce rtc 0x70 access vm-exit time

From: Paolo Bonzini
Date: Wed Aug 02 2017 - 04:50:22 EST


On 02/08/2017 10:45, peng.hao2@xxxxxxxxxx wrote:
>>On 02/08/2017 17:24, Peng Hao wrote:
> coalesced MMIO is async and io port should be sync . I don't need to
> coalese io port access.

Coalesced MMIO access is resolved on the next read from a coalesced MMIO
address or the next write to a non-coalescecd MMIO address. So it would
work perfectly for port 0x70. You would have to modify QEMU to split
the RTC I/O ports into two MemoryRegions.

Paolo