Re: A proposal to enhance RISC-V HPM (Hardware Performance Monitor)
Yes, there is no way for kernel to know whether it is running in HS-mode or VS-mode. We would like to keep it that way.
From: tech-privileged@... <tech-privileged@...> On Behalf Of Allen Baum
Sent: 05 August 2020 11:19
To: alankao <alankao@...>
Subject: Re: [RISC-V] [tech-privileged] A proposal to enhance RISC-V HPM (Hardware Performance Monitor)
I may be dense (I won't take a poll on that though), but if a kernel can detect that it is in S-mode vs. VSMode, that sounds like a buggy virtualization scheme. The kernel should (appear to) be in whatever mode it thinks it is, even if it is really in VU mode (with appropriate hypervisor work, and performance penalties, etc).
On Tue, Aug 4, 2020 at 9:52 PM alankao <alankao@...> wrote: