intel_pstate: Add trace point to report internal state.
Add perf trace event "power:pstate_sample" to report driver state to
aid in diagnosing issues reported against intel_pstate.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index fe91dad..7e257b2 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -51,6 +51,8 @@
return div_s64((int64_t)x << FRAC_BITS, (int64_t)y);
}
+static u64 energy_divisor;
+
struct sample {
int32_t core_pct_busy;
u64 aperf;
@@ -559,6 +561,7 @@
rdmsrl(MSR_IA32_APERF, aperf);
rdmsrl(MSR_IA32_MPERF, mperf);
+
cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
cpu->samples[cpu->sample_ptr].aperf = aperf;
cpu->samples[cpu->sample_ptr].mperf = mperf;
@@ -603,6 +606,7 @@
ctl = pid_calc(pid, busy_scaled);
steps = abs(ctl);
+
if (ctl < 0)
intel_pstate_pstate_increase(cpu, steps);
else
@@ -612,9 +616,24 @@
static void intel_pstate_timer_func(unsigned long __data)
{
struct cpudata *cpu = (struct cpudata *) __data;
+ struct sample *sample;
+ u64 energy;
intel_pstate_sample(cpu);
+
+ sample = &cpu->samples[cpu->sample_ptr];
+ rdmsrl(MSR_PKG_ENERGY_STATUS, energy);
+
intel_pstate_adjust_busy_pstate(cpu);
+
+ trace_pstate_sample(fp_toint(sample->core_pct_busy),
+ fp_toint(intel_pstate_get_scaled_busy(cpu)),
+ cpu->pstate.current_pstate,
+ sample->mperf,
+ sample->aperf,
+ div64_u64(energy, energy_divisor),
+ sample->freq);
+
intel_pstate_set_sample_time(cpu);
}
@@ -894,6 +913,7 @@
int cpu, rc = 0;
const struct x86_cpu_id *id;
struct cpu_defaults *cpu_info;
+ u64 units;
if (no_load)
return -ENODEV;
@@ -927,8 +947,12 @@
if (rc)
goto out;
+ rdmsrl(MSR_RAPL_POWER_UNIT, units);
+ energy_divisor = 1 << ((units >> 8) & 0x1f); /* bits{12:8} */
+
intel_pstate_debug_expose_params();
intel_pstate_sysfs_expose_params();
+
return rc;
out:
get_online_cpus();