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path: root/drivers/cpufreq/intel_pstate.c
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Diffstat (limited to 'drivers/cpufreq/intel_pstate.c')
-rw-r--r--drivers/cpufreq/intel_pstate.c46
1 files changed, 44 insertions, 2 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 17e566afbb41..08960a55eb27 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1939,13 +1939,51 @@ static int intel_cpufreq_verify_policy(struct cpufreq_policy *policy)
return 0;
}
+/* Use of trace in passive mode:
+ *
+ * In passive mode the trace core_busy field (also known as the
+ * performance field, and lablelled as such on the graphs; also known as
+ * core_avg_perf) is not needed and so is re-assigned to indicate if the
+ * driver call was via the normal or fast switch path. Various graphs
+ * output from the intel_pstate_tracer.py utility that include core_busy
+ * (or performance or core_avg_perf) have a fixed y-axis from 0 to 100%,
+ * so we use 10 to indicate the the normal path through the driver, and
+ * 90 to indicate the fast switch path through the driver.
+ * The scaled_busy field is not used, and is set to 0.
+ */
+
+#define INTEL_PSTATE_TRACE_TARGET 10
+#define INTEL_PSTATE_TRACE_FAST_SWITCH 90
+
+static void intel_cpufreq_trace(struct cpudata *cpu, unsigned int trace_type, int old_pstate)
+{
+ struct sample *sample;
+
+ if (!trace_pstate_sample_enabled())
+ return;
+
+ if (!intel_pstate_sample(cpu, ktime_get()))
+ return;
+
+ sample = &cpu->sample;
+ trace_pstate_sample(trace_type,
+ 0,
+ old_pstate,
+ cpu->pstate.current_pstate,
+ sample->mperf,
+ sample->aperf,
+ sample->tsc,
+ get_avg_frequency(cpu),
+ fp_toint(cpu->iowait_boost * 100));
+}
+
static int intel_cpufreq_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cpudata *cpu = all_cpu_data[policy->cpu];
struct cpufreq_freqs freqs;
- int target_pstate;
+ int target_pstate, old_pstate;
update_turbo_state();
@@ -1965,12 +2003,14 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy,
break;
}
target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
+ old_pstate = cpu->pstate.current_pstate;
if (target_pstate != cpu->pstate.current_pstate) {
cpu->pstate.current_pstate = target_pstate;
wrmsrl_on_cpu(policy->cpu, MSR_IA32_PERF_CTL,
pstate_funcs.get_val(cpu, target_pstate));
}
freqs.new = target_pstate * cpu->pstate.scaling;
+ intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_TARGET, old_pstate);
cpufreq_freq_transition_end(policy, &freqs, false);
return 0;
@@ -1980,13 +2020,15 @@ static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy,
unsigned int target_freq)
{
struct cpudata *cpu = all_cpu_data[policy->cpu];
- int target_pstate;
+ int target_pstate, old_pstate;
update_turbo_state();
target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling);
target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
+ old_pstate = cpu->pstate.current_pstate;
intel_pstate_update_pstate(cpu, target_pstate);
+ intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_FAST_SWITCH, old_pstate);
return target_pstate * cpu->pstate.scaling;
}