From: Stratos Karafotis <stratosk@semaphore.gr>
Date: Fri, 18 Jul 2014 15:37:27 +0000 (-0700)
Subject: cpufreq: intel_pstate: Remove core_pct rounding
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=78e2708691e9289f97750eb71aca31b5a2973d94;p=linux-beck.git

cpufreq: intel_pstate: Remove core_pct rounding

The specific rounding adds conditionally only 1/256 to fractional
part of core_pct.

We can safely remove it without any noticeable impact in
calculations.

Use div64_u64 instead of div_u64 to avoid possible overflow of
sample->mperf as divisor

Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
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 2ff85f665f93..c5eac949760d 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -545,13 +545,9 @@ static inline void intel_pstate_calc_busy(struct cpudata *cpu)
 {
 	struct sample *sample = &cpu->sample;
 	int64_t core_pct;
-	int32_t rem;
 
 	core_pct = int_tofp(sample->aperf) * int_tofp(100);
-	core_pct = div_u64_rem(core_pct, int_tofp(sample->mperf), &rem);
-
-	if ((rem << 1) >= int_tofp(sample->mperf))
-		core_pct += 1;
+	core_pct = div64_u64(core_pct, int_tofp(sample->mperf));
 
 	sample->freq = fp_toint(
 		mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));