cpufreq: intel_pstate: Simplify intel_pstate_update_perf_limits()
Because pstate.max_freq is always equal to the product of
pstate.max_pstate and pstate.scaling and, analogously,
pstate.turbo_freq is always equal to the product of
pstate.turbo_pstate and pstate.scaling, the result of the
max_policy_perf computation in intel_pstate_update_perf_limits() is
always equal to the quotient of policy_max and pstate.scaling,
regardless of whether or not turbo is disabled. Analogously, the
result of min_policy_perf in intel_pstate_update_perf_limits() is
always equal to the quotient of policy_min and pstate.scaling.
Accordingly, intel_pstate_update_perf_limits() need not check
whether or not turbo is enabled at all and in order to compute
max_policy_perf and min_policy_perf it can always divide policy_max
and policy_min, respectively, by pstate.scaling. Make it do so.
While at it, move the definition and initialization of the
turbo_max local variable to the code branch using it.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 2ef9584..f040106 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2195,9 +2195,8 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
unsigned int policy_min,
unsigned int policy_max)
{
+ int scaling = cpu->pstate.scaling;
int32_t max_policy_perf, min_policy_perf;
- int max_state, turbo_max;
- int max_freq;
/*
* HWP needs some special consideration, because HWP_REQUEST uses
@@ -2206,33 +2205,24 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
if (hwp_active)
intel_pstate_get_hwp_cap(cpu);
- if (global.no_turbo || global.turbo_disabled) {
- max_state = cpu->pstate.max_pstate;
- max_freq = cpu->pstate.max_freq;
- } else {
- max_state = cpu->pstate.turbo_pstate;
- max_freq = cpu->pstate.turbo_freq;
- }
-
- turbo_max = cpu->pstate.turbo_pstate;
-
- max_policy_perf = max_state * policy_max / max_freq;
+ max_policy_perf = policy_max / scaling;
if (policy_max == policy_min) {
min_policy_perf = max_policy_perf;
} else {
- min_policy_perf = max_state * policy_min / max_freq;
+ min_policy_perf = policy_min / scaling;
min_policy_perf = clamp_t(int32_t, min_policy_perf,
0, max_policy_perf);
}
- pr_debug("cpu:%d max_state %d min_policy_perf:%d max_policy_perf:%d\n",
- cpu->cpu, max_state, min_policy_perf, max_policy_perf);
+ pr_debug("cpu:%d min_policy_perf:%d max_policy_perf:%d\n",
+ cpu->cpu, min_policy_perf, max_policy_perf);
/* Normalize user input to [min_perf, max_perf] */
if (per_cpu_limits) {
cpu->min_perf_ratio = min_policy_perf;
cpu->max_perf_ratio = max_policy_perf;
} else {
+ int turbo_max = cpu->pstate.turbo_pstate;
int32_t global_min, global_max;
/* Global limits are in percent of the maximum turbo P-state. */