On Tue, 2017-07-25 at 01:46 +0000, Huaisheng HS1 Ye wrote:
> Hi Rafael,
>
> If you delete "get" function implement within intel_pstate, the
> sysfs interface cpuinfo_cur_freq will display <unknown> all the
> time.
cpuinfo_cur_freq by definition should show actual frequency HW
frequency. Unless I missed something. So Len Brown's patch should also
take care of this to get from arch specific function is available.
So in addition to Rafael's change, what about this?
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 9bf97a3..29ec687 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -689,8 +689,13 @@ store_one(scaling_max_freq, max);
static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
char *buf)
{
- unsigned int cur_freq = __cpufreq_get(policy);
+ unsigned int cur_freq;
+ cur_freq = arch_freq_get_on_cpu(policy->cpu);
+ if (cur_freq)
+ return sprintf(buf, "%u\n", cur_freq);
+
+ cur_freq = __cpufreq_get(policy);
if (cur_freq)
return sprintf(buf, "%u\n", cur_freq);
Thanks,
Srinivas
> To be honest, at the beginning I have consider this way like you
> patched, but based two reasons below, it is conservative for us to do
> that.
>
> 1. I am worried about whether it would lead to confusion for
> customers or
> Linux OS venders who are accustomed to cpuinfo_cur_freq.
> 2. This is the first time for me to offer patch to intel_pstate, not
> sure
> whether it could be accepted by you.
>
> >
> > On Monday, July 24, 2017 03:32:47 PM Huaisheng HS1 Ye wrote:
> > >
> > > Hi Rafael,
> > > Thanks for your reply.
> > >
> > > >
> > > > On Monday, July 24, 2017 05:43:14 AM Huaisheng HS1 Ye wrote:
> > > > >
> > > > > After commit 82b4e03e01bc (intel_pstate: skip scheduler hook
> > > > > when
> > > > > in "performance" mode) Software P-state control modes
> > > > > couldn't get
> > > > > dynamic value during performance mode,
> > > > Please explain what you mean here.
> > > >
> > > commit 82b4e03e01bc (intel_pstate: skip scheduler hook when in
> > > "performance" mode) disables intel_pstate_set_update_util_hook
> > > when
> > > current policy is performance within function
> > > intel_pstate_set_policy.
> > > It leads to Software P-states couldn't update sysfs interface
> > > cpuinfo_cur_freq's value during performance mode, because of
> > > pstate_funcs.update_util couldn't set for the given CPU.
> > >
> > > >
> > > > I guess you carried out some tests and the results were not as
> > > > expected, so what was the test?
> > > Exactly, we check the sysfs interface cpuinfo_cur_freq and the
> > > output
> > > of cpupower frequency-info both with performance mode.
> > OK, so what about the change below:
> >
> > ---
> > drivers/cpufreq/intel_pstate.c | 8 --------
> > 1 file changed, 8 deletions(-)
> >
> > Index: linux-pm/drivers/cpufreq/intel_pstate.c
> > ==============================================================
> > =====
> > --- linux-pm.orig/drivers/cpufreq/intel_pstate.c
> > +++ linux-pm/drivers/cpufreq/intel_pstate.c
> > @@ -1674,13 +1674,6 @@ static int intel_pstate_init_cpu(unsigne
> > return 0;
> > }
> >
> > -static unsigned int intel_pstate_get(unsigned int cpu_num) -{
> > - struct cpudata *cpu = all_cpu_data[cpu_num];
> > -
> > - return cpu ? get_avg_frequency(cpu) : 0;
> > -}
> > -
> > static void intel_pstate_set_update_util_hook(unsigned int
> > cpu_num) {
> > struct cpudata *cpu = all_cpu_data[cpu_num]; @@ -1921,7
> > +1914,6 @@
> > static struct cpufreq_driver intel_pstat
> > .setpolicy = intel_pstate_set_policy,
> > .suspend = intel_pstate_hwp_save_state,
> > .resume = intel_pstate_resume,
> > - .get = intel_pstate_get,
> > .init = intel_pstate_cpu_init,
> > .exit = intel_pstate_cpu_exit,
> > .stop_cpu = intel_pstate_stop_cpu,
