cpufreq / intel_pstate: use lowest requested max performance
There are two ways that the maximum p-state can be clamped, via a
policy change and via the sysfs file.
The acpi-thermal driver adjusts the p-state policy in response to
thermal events. These changes override the users settings at the
moment.
Use the lowest of the two requested values this ensures that we will
not exceed the requested pstate from either mechanism.
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
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 c6e10d0..4a437ff 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -117,6 +117,8 @@
int min_perf_pct;
int32_t max_perf;
int32_t min_perf;
+ int max_policy_pct;
+ int max_sysfs_pct;
};
static struct perf_limits limits = {
@@ -125,6 +127,8 @@
.max_perf = int_tofp(1),
.min_perf_pct = 0,
.min_perf = 0,
+ .max_policy_pct = 100,
+ .max_sysfs_pct = 100,
};
static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
@@ -295,7 +299,8 @@
if (ret != 1)
return -EINVAL;
- limits.max_perf_pct = clamp_t(int, input, 0 , 100);
+ limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
+ limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
return count;
}
@@ -646,8 +651,9 @@
limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
- limits.max_perf_pct = policy->max * 100 / policy->cpuinfo.max_freq;
- limits.max_perf_pct = clamp_t(int, limits.max_perf_pct, 0 , 100);
+ limits.max_policy_pct = policy->max * 100 / policy->cpuinfo.max_freq;
+ limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
+ limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
return 0;