cpufreq: intel_pstate: Do not walk policy->cpus

intel_pstate_hwp_set() is the only function walking policy->cpus
in intel_pstate.  The rest of the code simply assumes one CPU per
policy, including the initialization code.

Therefore it doesn't make sense for intel_pstate_hwp_set() to
walk policy->cpus as it is guaranteed to have only one bit set
for policy->cpu.

For this reason, rearrange intel_pstate_hwp_set() to take the CPU
number as the argument and drop the loop over policy->cpus from it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 60 insertions, 64 deletions

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 6384557cea69..5236701958d0 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -792,84 +792,80 @@ static struct freq_attr *hwp_cpufreq_attrs[] = {
         NULL,
 };
 
-static void intel_pstate_hwp_set(struct cpufreq_policy *policy)
+static void intel_pstate_hwp_set(unsigned int cpu)
 {
-        int min, hw_min, max, hw_max, cpu;
+        struct cpudata *cpu_data = all_cpu_data[cpu];
+        int min, hw_min, max, hw_max;
         u64 value, cap;
+        s16 epp;
 
-        for_each_cpu(cpu, policy->cpus) {
-                struct cpudata *cpu_data = all_cpu_data[cpu];
-                s16 epp;
-
-                rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
-                hw_min = HWP_LOWEST_PERF(cap);
-                if (global.no_turbo)
-                        hw_max = HWP_GUARANTEED_PERF(cap);
-                else
-                        hw_max = HWP_HIGHEST_PERF(cap);
-
-                max = fp_ext_toint(hw_max * cpu_data->max_perf);
-                if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
-                        min = max;
-                else
-                        min = fp_ext_toint(hw_max * cpu_data->min_perf);
+        rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
+        hw_min = HWP_LOWEST_PERF(cap);
+        if (global.no_turbo)
+                hw_max = HWP_GUARANTEED_PERF(cap);
+        else
+                hw_max = HWP_HIGHEST_PERF(cap);
 
-                rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
+        max = fp_ext_toint(hw_max * cpu_data->max_perf);
+        if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
+                min = max;
+        else
+                min = fp_ext_toint(hw_max * cpu_data->min_perf);
 
-                value &= ~HWP_MIN_PERF(~0L);
-                value |= HWP_MIN_PERF(min);
+        rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
 
-                value &= ~HWP_MAX_PERF(~0L);
-                value |= HWP_MAX_PERF(max);
+        value &= ~HWP_MIN_PERF(~0L);
+        value |= HWP_MIN_PERF(min);
 
-                if (cpu_data->epp_policy == cpu_data->policy)
-                        goto skip_epp;
+        value &= ~HWP_MAX_PERF(~0L);
+        value |= HWP_MAX_PERF(max);
 
-                cpu_data->epp_policy = cpu_data->policy;
+        if (cpu_data->epp_policy == cpu_data->policy)
+                goto skip_epp;
 
-                if (cpu_data->epp_saved >= 0) {
-                        epp = cpu_data->epp_saved;
-                        cpu_data->epp_saved = -EINVAL;
-                        goto update_epp;
-                }
+        cpu_data->epp_policy = cpu_data->policy;
 
-                if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE) {
-                        epp = intel_pstate_get_epp(cpu_data, value);
-                        cpu_data->epp_powersave = epp;
-                        /* If EPP read was failed, then don't try to write */
-                        if (epp < 0)
-                                goto skip_epp;
+        if (cpu_data->epp_saved >= 0) {
+                epp = cpu_data->epp_saved;
+                cpu_data->epp_saved = -EINVAL;
+                goto update_epp;
+        }
 
+        if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE) {
+                epp = intel_pstate_get_epp(cpu_data, value);
+                cpu_data->epp_powersave = epp;
+                /* If EPP read was failed, then don't try to write */
+                if (epp < 0)
+                        goto skip_epp;
 
-                        epp = 0;
-                } else {
-                        /* skip setting EPP, when saved value is invalid */
-                        if (cpu_data->epp_powersave < 0)
-                                goto skip_epp;
+                epp = 0;
+        } else {
+                /* skip setting EPP, when saved value is invalid */
+                if (cpu_data->epp_powersave < 0)
+                        goto skip_epp;
 
-                        /*
-                         * No need to restore EPP when it is not zero. This
-                         * means:
-                         *  - Policy is not changed
-                         *  - user has manually changed
-                         *  - Error reading EPB
-                         */
-                        epp = intel_pstate_get_epp(cpu_data, value);
-                        if (epp)
-                                goto skip_epp;
+                /*
+                 * No need to restore EPP when it is not zero. This
+                 * means:
+                 *  - Policy is not changed
+                 *  - user has manually changed
+                 *  - Error reading EPB
+                 */
+                epp = intel_pstate_get_epp(cpu_data, value);
+                if (epp)
+                        goto skip_epp;
 
-                        epp = cpu_data->epp_powersave;
-                }
+                epp = cpu_data->epp_powersave;
+        }
 update_epp:
-                if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
-                        value &= ~GENMASK_ULL(31, 24);
-                        value |= (u64)epp << 24;
-                } else {
-                        intel_pstate_set_epb(cpu, epp);
-                }
-skip_epp:
-                wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
+        if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
+                value &= ~GENMASK_ULL(31, 24);
+                value |= (u64)epp << 24;
+        } else {
+                intel_pstate_set_epb(cpu, epp);
         }
+skip_epp:
+        wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
 }
 
 static int intel_pstate_hwp_save_state(struct cpufreq_policy *policy)
@@ -892,7 +888,7 @@ static int intel_pstate_resume(struct cpufreq_policy *policy)
         mutex_lock(&intel_pstate_limits_lock);
 
         all_cpu_data[policy->cpu]->epp_policy = 0;
-        intel_pstate_hwp_set(policy);
+        intel_pstate_hwp_set(policy->cpu);
 
         mutex_unlock(&intel_pstate_limits_lock);
 
@@ -2057,7 +2053,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
         intel_pstate_set_update_util_hook(policy->cpu);
 
         if (hwp_active)
-                intel_pstate_hwp_set(policy);
+                intel_pstate_hwp_set(policy->cpu);
 
         mutex_unlock(&intel_pstate_limits_lock);