<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style></style> </head> <body lang="EN-US" link="blue" vlink="purple"> <div class="WordSection1"> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <div style="border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt"> <div> <div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in"> <p class="MsoNormal"><b>From:</b> Rodrigo Vivi <rodrigo.vivi@gmail.com> <br> <b>Sent:</b> Friday, January 22, 2021 1:26 AM<br> <b>To:</b> Chris Wilson <chris@chris-wilson.co.uk><br> <b>Cc:</b> Gupta, Anshuman <anshuman.gupta@intel.com>; igt-dev@lists.freedesktop.org<br> <b>Subject:</b> Re: [igt-dev] [PATCH i-g-t 2/6] i915/i915_pm_rpm.c: create PC state subtest group<o:p></o:p></p> </div> </div> <p class="MsoNormal"><o:p> </o:p></p> <div> <div> <p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p> </div> <p class="MsoNormal"><o:p> </o:p></p> <div> <div> <p class="MsoNormal">On Thu, Dec 10, 2020 at 2:42 AM Chris Wilson <<a href="mailto:chris@chris-wilson.co.uk">chris@chris-wilson.co.uk</a>> wrote:<o:p></o:p></p> </div> <blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in"> <p class="MsoNormal">Quoting Anshuman Gupta (2020-12-10 05:02:48)<br> > On 2020-12-09 at 16:47:01 +0000, Chris Wilson wrote:<br> > > Quoting Anshuman Gupta (2020-12-09 16:25:02)<br> > > > On 2020-12-09 at 16:25:55 +0000, Chris Wilson wrote:<br> > > > > Quoting Anshuman Gupta (2020-12-09 16:06:38)<br> > > > > > Create a separate igt test group and move package C<br> > > > > > state in to this subgroup.<br> > > > > > Run powertop --auto-tune to tune SOC power configuration<br> > > > > > for package C state tests.<br> > > > > > <br> > > > > > Signed-off-by: Anshuman Gupta <<a href="mailto:anshuman.gupta@intel.com" target="_blank">anshuman.gupta@intel.com</a>><br> > > > > > ---<br> > > > > > tests/i915/i915_pm_rpm.c | 35 +++++++++++++++++++++++++++++++----<br> > > > > > 1 file changed, 31 insertions(+), 4 deletions(-)<br> > > > > > <br> > > > > > diff --git a/tests/i915/i915_pm_rpm.c b/tests/i915/i915_pm_rpm.c<br> > > > > > index af55b569..42bc44d9 100644<br> > > > > > --- a/tests/i915/i915_pm_rpm.c<br> > > > > > +++ b/tests/i915/i915_pm_rpm.c<br> > > > > > @@ -832,6 +832,25 @@ static void basic_subtest(void)<br> > > > > > /* XXX Also we can test wake up via exec nop */<br> > > > > > }<br> > > > > > <br> > > > > > +static bool setup_powertop(void)<br> > > > > > +{<br> > > > > > + FILE *fp;<br> > > > > > + char tmp[512];<br> > > > > > +<br> > > > > > + fp = popen("powertop --auto-tune", "r");<br> > > > > <br> > > > > Doesn't this defeat the point of having it work out of the box?<br> > May be misunderstood your comment, is it PC state or powertop should work<br> > out of box ?<br> <br> Powermanagement should not require the user to configure it before it<br> can work.<br> <br> powertop in particular may tweak the gfx, which is verboten.<br> <br> Manually perform any configuration you think is required, and warn if the<br> initial configuration does not support reaching the lowest pc state the<br> system can. File bugs.<o:p></o:p></p> </blockquote> <div> <p class="MsoNormal"><o:p> </o:p></p> </div> <div> <p class="MsoNormal">I understand why Anshuman did this. There are many many components<o:p></o:p></p> </div> <div> <p class="MsoNormal">out there that are blocking the PC10 and this powertop --auto-tune<o:p></o:p></p> </div> <div> <p class="MsoNormal">is trying to take care of all the corner cases to get the "best" of all the<o:p></o:p></p> </div> <div> <p class="MsoNormal">components so we can try to garantee that we are not getting blocked by other components.<o:p></o:p></p> </div> <div> <p class="MsoNormal"><o:p> </o:p></p> </div> <div> <p class="MsoNormal">However this is very very dangerous. It toggles a lot of unsafe and untested cases.<o:p></o:p></p> </div> <div> <p class="MsoNormal"><o:p> </o:p></p> </div> <div> <p class="MsoNormal">I have lost a laptop right after a powertop --auto-tune and have never used that<o:p></o:p></p> </div> <div> <p class="MsoNormal">in my life again. Coincidence? Maybe... but I don't want to take the risk in my<o:p></o:p></p> </div> <div> <p class="MsoNormal">machine and I definitely cannot recommend its use.<o:p></o:p></p> <p class="MsoNormal">Thanks Rodrigo for comment.<o:p></o:p></p> <p class="MsoNormal">Actually as part of manual validation powertop being used by different PnP Val team.<o:p></o:p></p> <p class="MsoNormal">Without using powertop surely we are not going to hit PC8/PC10 in that case I am afraid that<o:p></o:p></p> <p class="MsoNormal">these test can’t be part of automatic validation in CI.<o:p></o:p></p> <p class="MsoNormal">We may need to find alternative in some sort of OS level Power Management Policy decision maker, <o:p></o:p></p> <p class="MsoNormal">which can decide conservative power saving oriented policy.<o:p></o:p></p> <p class="MsoNormal">Runtime idle with display on which leads to PC10 and s0ix effectively for client products, <o:p></o:p></p> <p class="MsoNormal">Ubuntu OS looks like not really tuned for that. <o:p></o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal">Thanks,<o:p></o:p></p> <p class="MsoNormal">Anshuman Gupta.<o:p></o:p></p> </div> <div> <p class="MsoNormal"> <o:p></o:p></p> </div> <blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in"> <p class="MsoNormal">-Chris<br> _______________________________________________<br> igt-dev mailing list<br> <a href="mailto:igt-dev@lists.freedesktop.org" target="_blank">igt-dev@lists.freedesktop.org</a><br> <a href="https://lists.freedesktop.org/mailman/listinfo/igt-dev" target="_blank">https://lists.freedesktop.org/mailman/listinfo/igt-dev</a><o:p></o:p></p> </blockquote> </div> </div> </div> </div> </body> </html>