Latency measure VM_EXITs of storage IO interrupts

[enterJazz]

To measure the VM_EXIT latency, we must modify the kernel.

Bifrost does it as such:

IPADS-Bifrost/cvm-opt-guest@91c41f9

[enterJazz]

For prelim VM_EXIT measurements:

https://github.com/TUM-DSE/CVM_eval/tree/main/benchmarks
this directory contains microbenchmarks of cpuid time, which causes vmexit

Hence: we can measure latency of VM_EXIT vs CVM_EXIT itself. Note: this does not replace the latency diff we are looking for wrt. storage IO interrupts

[enterJazz]

For prelim VM_EXIT measurements:

https://github.com/TUM-DSE/CVM_eval/tree/main/benchmarks this directory contains microbenchmarks of cpuid time, which causes vmexit

Hence: we can measure latency of VM_EXIT vs CVM_EXIT itself. Note: this does not replace the latency diff we are looking for wrt. storage IO interrupts

Weird results for prelim VM_EXIT:

for sev-snp, i get 631ns on avg per cpuid, whereas in native, i get 1234ns.