cpufreq: intel_pstate: Add locking around HWP requests
To avoid race conditions from multiple threads, increase the scope
of intel_pstate_limits_lock to include HWP requests also.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject ]
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 a7f597a..c7f596f 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -853,11 +853,11 @@
limits->no_turbo = clamp_t(int, input, 0, 1);
- mutex_unlock(&intel_pstate_limits_lock);
-
if (hwp_active)
intel_pstate_hwp_set_online_cpus();
+ mutex_unlock(&intel_pstate_limits_lock);
+
return count;
}
@@ -882,10 +882,11 @@
limits->max_perf_pct);
limits->max_perf = div_ext_fp(limits->max_perf_pct, 100);
- mutex_unlock(&intel_pstate_limits_lock);
-
if (hwp_active)
intel_pstate_hwp_set_online_cpus();
+
+ mutex_unlock(&intel_pstate_limits_lock);
+
return count;
}
@@ -910,10 +911,11 @@
limits->min_perf_pct);
limits->min_perf = div_ext_fp(limits->min_perf_pct, 100);
- mutex_unlock(&intel_pstate_limits_lock);
-
if (hwp_active)
intel_pstate_hwp_set_online_cpus();
+
+ mutex_unlock(&intel_pstate_limits_lock);
+
return count;
}
@@ -1664,7 +1666,6 @@
static void intel_pstate_set_performance_limits(struct perf_limits *limits)
{
- mutex_lock(&intel_pstate_limits_lock);
limits->no_turbo = 0;
limits->turbo_disabled = 0;
limits->max_perf_pct = 100;
@@ -1675,15 +1676,12 @@
limits->max_sysfs_pct = 100;
limits->min_policy_pct = 0;
limits->min_sysfs_pct = 0;
- mutex_unlock(&intel_pstate_limits_lock);
}
static void intel_pstate_update_perf_limits(struct cpufreq_policy *policy,
struct perf_limits *limits)
{
- mutex_lock(&intel_pstate_limits_lock);
-
limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100,
policy->cpuinfo.max_freq);
limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0, 100);
@@ -1714,8 +1712,6 @@
limits->max_perf = round_up(limits->max_perf, EXT_FRAC_BITS);
limits->min_perf = round_up(limits->min_perf, EXT_FRAC_BITS);
- mutex_unlock(&intel_pstate_limits_lock);
-
pr_debug("cpu:%d max_perf_pct:%d min_perf_pct:%d\n", policy->cpu,
limits->max_perf_pct, limits->min_perf_pct);
}
@@ -1744,6 +1740,8 @@
if (per_cpu_limits)
perf_limits = cpu->perf_limits;
+ mutex_lock(&intel_pstate_limits_lock);
+
if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
if (!perf_limits) {
limits = &performance_limits;
@@ -1778,6 +1776,8 @@
intel_pstate_hwp_set_policy(policy);
+ mutex_unlock(&intel_pstate_limits_lock);
+
return 0;
}