回复: [External] Re: [PATCH] tools/power turbostat: Fix Bzy_MHz calculation equation

[Peng Peng17 Liu]

Len,

The new commit message is better. Thanks for your help😊

Regards,
Peng

-----邮件原件-----
发件人: Len Brown <lenb@xxxxxxxxxx> 
发送时间: 2023年11月28日 9:40
收件人: Doug Smythies <dsmythies@xxxxxxxxx>
抄送: Peng Liu <pngliu@xxxxxxxxxxx>; Wyes Karny <wyes.karny@xxxxxxx>; linux-pm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Peng Peng17 Liu <liupeng17@xxxxxxxxxx>
主题: [External] Re: [PATCH] tools/power turbostat: Fix Bzy_MHz calculation equation

Peng Liu,
Thanks for the close read of the documentation, and the patch.
I've applied it, though I re-wrote the commit message (below) to make it clear it is a documentation fix, as the code was already correct.

thanks,
-Len

ps. I would have replied to your original e-mail, but there was a period where gmail dropped mail due to space limitations.
No worries, as Doug said, everything is in patchwork.


    tools/power turbostat: Fix Bzy_MHz documentation typo

    The code calculates Bzy_MHz by multiplying TSC_delta * APERF_delta/MPERF_delta
    The man page erroneously showed that TSC_delta was divided.

On Thu, Nov 2, 2023 at 11:31 AM Doug Smythies <dsmythies@xxxxxxxxx> wrote:
>
> Hi Peng and Wyes,
>
> Just for your information about your recent "ping"s about your turbostat patches:
>
> Please be aware that there is rarely any reply. There tends to be 
> about 2 turbostat updates released per year. Your patches are in patchworks [1], as are some others, including an old one of mine from 2023.04.03 Eventually there will be an update, and hopefully it will include all our patches.
>
> [1] 
> https://apc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatc
> hwork.kernel.org%2Fproject%2Flinux-pm%2Flist%2F%3Fseries%3D%26submitte
> r%3D%26state%3D%26q%3D%26archive%3D%26delegate%3D107&data=05%7C01%7Cli
> upeng17%40lenovo.com%7Cb4cd61b01e3b4d8b79ae08dbefb2f521%7C5c7d0b28bdf8
> 410caa934df372b16203%7C0%7C0%7C638367324123743896%7CUnknown%7CTWFpbGZs
> b3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D
> %7C3000%7C%7C%7C&sdata=nsw8vwV2oSAOBVGWTu6PAFeMPhpnZM8AXtzXWpoaRgw%3D&
> reserved=0
>
> ... Doug
>
> On 2023.10.29 08:12 Peng Liu wrote:
>
> > Ping
> >
> > On 2023/10/7 13:46, Peng Liu wrote:
> >> From: Peng Liu <liupeng17@xxxxxxxxxx>
> >>
> >> To calculate Bzy_MHz, TSC_delta should multiply APERF_delta instead 
> >> of dividing it.
> >>
> >> Signed-off-by: Peng Liu <liupeng17@xxxxxxxxxx>
> >> ---
> >>   tools/power/x86/turbostat/turbostat.8 | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/tools/power/x86/turbostat/turbostat.8 
> >> b/tools/power/x86/turbostat/turbostat.8
> >> index 8f08c3fd498d..1ba6340d3b3d 100644
> >> --- a/tools/power/x86/turbostat/turbostat.8
> >> +++ b/tools/power/x86/turbostat/turbostat.8
> >> @@ -370,7 +370,7 @@ below the processor's base frequency.
> >>
> >>   Busy% = MPERF_delta/TSC_delta
> >>
> >> -Bzy_MHz = TSC_delta/APERF_delta/MPERF_delta/measurement_interval
> >> +Bzy_MHz = TSC_delta*APERF_delta/MPERF_delta/measurement_interval
> >>
> >>   Note that these calculations depend on TSC_delta, so they
> >>   are not reliable during intervals when TSC_MHz is not running at the base frequency.
>


--
Len Brown, Intel