On Thu, Aug 13, 2015 at 01:25:29AM +0000, Li, Liang Z wrote: > Hi Paolo & Marcelo, > > Could please point out what issue the patch 317b0a6d8ba44e try to fix? I > found in live migration the cpu_synchronize_all_states will be called twice, > and it will take more than 1 ms sometimes. I try to do some optimization but > lack the knowledge about the background.
What the code in 317b0a6d8ba44e requires is to retrieve the TSC value from the kernel. Perhaps you can trace kvm_arch_get_regs and look why its taking that amount of time and what can be done to improve it.
