cpufreq: intel_pstate: Fix sysfs limits enforcement for performance policy

A side effect of keeping intel_pstate sysfs limits in sync with cpufreq
is that the now sysfs limits can't enforced under performance policy.

For example, if the max_perf_pct is changed from 100 to 80, this will call
intel_pstate_set_policy(), which will change the max_perf to 100 again for
performance policy. Same issue happens, when no_turbo is set.

This change calculates max and min frequency using sysfs performance
limits in intel_pstate_verify_policy() and adjusts policy limits by
calling cpufreq_verify_within_limits().

Also, it causes the setting of performance limits to be skipped if
no_turbo is set.

Fixes: 111b8b3fe4fa (cpufreq: intel_pstate: Always keep all limits settings in sync)
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.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 e261438cd6905b537598194622968e4f2136afb6..ed215c5592f6245309ee38cc96487fdbf25fbd56 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1951,7 +1951,8 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
                        limits = &performance_limits;
                        perf_limits = limits;
                }
-               if (policy->max >= policy->cpuinfo.max_freq) {
+               if (policy->max >= policy->cpuinfo.max_freq &&
+                   !limits->no_turbo) {
                        pr_debug("set performance\n");
                        intel_pstate_set_performance_limits(perf_limits);
                        goto out;
@@ -1993,6 +1994,17 @@ static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
            policy->policy != CPUFREQ_POLICY_PERFORMANCE)
                return -EINVAL;
 
+       /* When per-CPU limits are used, sysfs limits are not used */
+       if (!per_cpu_limits) {
+               unsigned int max_freq, min_freq;
+
+               max_freq = policy->cpuinfo.max_freq *
+                                               limits->max_sysfs_pct / 100;
+               min_freq = policy->cpuinfo.max_freq *
+                                               limits->min_sysfs_pct / 100;
+               cpufreq_verify_within_limits(policy, min_freq, max_freq);
+       }
+
        return 0;
 }