Re: [RFC PATCH 2/4] x86, mwaitt: introduce mwaitx idle with a configurable timer

Ingo Molnar
2015-05-25T10:43:56Z

* Huang Rui <ray.huang@amd.com> wrote:

> No, the timeout value doesn't decide how 'deep' the power state
> enters. Basically, the same power consumption with any timeout.
>
> I summarized the comparison of mwait and mwaitx
>
> MWAIT MWAITX
> opcode 0f 01 c9 | 0f 01 fb
> ECX[0] value of RFLAGS.IF seen by instruction
> ECX[1] unused/#GP if set | enable timer if set
> ECX[31:2] unused/#GP if set
> EAX unused
> EBX[31:0] unused | max wait time (loops)
>
>
> MONITOR MONITORX
> opcode 0f 01 c8 | 0f 01 fa
> EAX (logical) address to monitor
> ECX #GP if not zero

Ok, thanks for the clarification!

Thanks,

Ingo