I refined/uploaded again, kindly advise.
On Fri, 2016-09-09 at 17:11 +0200, Thomas Gleixner wrote:
> On Fri, 9 Sep 2016, Harry Pan wrote:
> > - if (apply_quirk)
> > + if (apply_quirk == RAPL_HSX_QUIRK)
> > rapl_hw_unit[RAPL_IDX_RAM_NRG_STAT] = 16;
> >
> > /*
> > + * Some Atom processors (BYT/BSW) have 2^ESU microjoules increment,
> > + * refer to Software Developers' Manual, Vol. 3C, Order No. 325384,
> > + * Table 35-8 of MSR_RAPL_POWER_UNIT
> > + */
> > + if (apply_quirk == RAPL_BYT_QUIRK) {
> > + for (i = 0; i < NR_RAPL_DOMAINS; i++)
> > + rapl_hw_unit[i] = 32 - rapl_hw_unit[i];
> > + }
>
> switch(quirk) if at all, but see below.
Yes, v3 I refined as switch.
>
> > + /*
> > * Calculate the timer rate:
> > * Use reference of 200W for scaling the timeout to avoid counter
> > * overflows. 200W = 200 Joules/sec
> > @@ -702,47 +742,53 @@ static int __init init_rapl_pmus(void)
> > { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&init }
> >
> > struct intel_rapl_init_fun {
> > - bool apply_quirk;
> > + enum rapl_quirk apply_quirk;
>
> This is silly. Make apply_quirk a function pointer and provide functions
> for the different quirks.
I read the rapl_check_hw_unit() as: read MSR_RAPL_POWER_UNIT, apply
quirk if need, then estimate timer rate.
In case to refine struct intel_rapl_init_fun adding callback, then
either the quirk moving outside the rapl_check_hw_unit(), or replace
input parameter as whole rapl_init in order to assess quirk callback, by
far it looks to me centralize these two quirks inside this function more
easily to maintain.
>
> > int cntr_mask;
> > struct attribute **attrs;
> > };
> >
> > static const struct intel_rapl_init_fun snb_rapl_init __initconst = {
> > - .apply_quirk = false,
> > + .apply_quirk = RAPL_NO_QUIRK,
>
> Zero ininitalization has no real value other than consuming state space.
To enable more than one quirk I extended bool to enum, I thought the
__initconst space would be freed after kernel initialized, is there more
detail concern I missed?
Sincerely,
Harry
