On 05/08/19 13:37, Christian Borntraeger wrote: > While have ONE_REG will certainly work, have you considered the sync_reg scheme > (registers as part of kvm_run structure) > This will speed up the exit to QEMU as you do not have to do multiple ioctls > (each imposing a systemcall overhead) for one exit. > > Ideally you should not exit too often into qemu, but for those cases sync_regs > is faster than ONE_REG. At least in theory, RISC-V should never have exits to QEMU that need accessing the registers. (The same is true for x86; Google implemented sync_regs because they moved the instruction emulator to userspace in their fork). Paolo
