[PATCH 3.14 63/78] intel_pstate: remove unneeded sample buffers

Greg Kroah-Hartman
2014-06-09T22:59:25Z

From: Dirk Brandewie <dirk.j.brandewie@intel.com>

commit d37e2b764499e092ebc493d6f980827feb952e23 upstream.

Remove unneeded sample buffers, intel_pstate operates on the most
recent sample only. This save some memory and make the code more
readable.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/cpufreq/intel_pstate.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)

--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -101,8 +101,7 @@ struct cpudata {
u64 prev_aperf;
u64 prev_mperf;
unsigned long long prev_tsc;
- int sample_ptr;
- struct sample samples[SAMPLE_COUNT];
+ struct sample sample;
};

static struct cpudata **all_cpu_data;
@@ -590,15 +589,14 @@ static inline void intel_pstate_sample(s
mperf = mperf >> FRAC_BITS;
tsc = tsc >> FRAC_BITS;

- cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
- cpu->samples[cpu->sample_ptr].aperf = aperf;
- cpu->samples[cpu->sample_ptr].mperf = mperf;
- cpu->samples[cpu->sample_ptr].tsc = tsc;
- cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf;
- cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf;
- cpu->samples[cpu->sample_ptr].tsc -= cpu->prev_tsc;
+ cpu->sample.aperf = aperf;
+ cpu->sample.mperf = mperf;
+ cpu->sample.tsc = tsc;
+ cpu->sample.aperf -= cpu->prev_aperf;
+ cpu->sample.mperf -= cpu->prev_mperf;
+ cpu->sample.tsc -= cpu->prev_tsc;

- intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]);
+ intel_pstate_calc_busy(cpu, &cpu->sample);

cpu->prev_aperf = aperf;
cpu->prev_mperf = mperf;
@@ -618,7 +616,7 @@ static inline int32_t intel_pstate_get_s
{
int32_t core_busy, max_pstate, current_pstate;

- core_busy = cpu->samples[cpu->sample_ptr].core_pct_busy;
+ core_busy = cpu->sample.core_pct_busy;
max_pstate = int_tofp(cpu->pstate.max_pstate);
current_pstate = int_tofp(cpu->pstate.current_pstate);
core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
@@ -652,7 +650,7 @@ static void intel_pstate_timer_func(unsi

intel_pstate_sample(cpu);

- sample = &cpu->samples[cpu->sample_ptr];
+ sample = &cpu->sample;

intel_pstate_adjust_busy_pstate(cpu);

@@ -727,7 +725,7 @@ static unsigned int intel_pstate_get(uns
cpu = all_cpu_data[cpu_num];
if (!cpu)
return 0;
- sample = &cpu->samples[cpu->sample_ptr];
+ sample = &cpu->sample;
return sample->freq;
}