return 0;
}
-static inline void
-enable_policy_freq_counters(int cpu, cpumask_var_t valid_cpus)
-{
- struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
-
- if (!policy) {
- pr_debug("CPU%d: No cpufreq policy found.\n", cpu);
- return;
- }
-
- if (cpumask_subset(policy->related_cpus, valid_cpus))
- cpumask_or(amu_fie_cpus, policy->related_cpus,
- amu_fie_cpus);
-
- cpufreq_cpu_put(policy);
-}
-
static DEFINE_STATIC_KEY_FALSE(amu_fie_key);
#define amu_freq_invariant() static_branch_unlikely(&amu_fie_key)
-static int __init init_amu_fie(void)
+static void amu_fie_setup(const struct cpumask *cpus)
{
- cpumask_var_t valid_cpus;
bool invariant;
- int ret = 0;
int cpu;
- if (!zalloc_cpumask_var(&valid_cpus, GFP_KERNEL))
- return -ENOMEM;
-
- if (!zalloc_cpumask_var(&amu_fie_cpus, GFP_KERNEL)) {
- ret = -ENOMEM;
- goto free_valid_mask;
- }
+ /* We are already set since the last insmod of cpufreq driver */
+ if (unlikely(cpumask_subset(cpus, amu_fie_cpus)))
+ return;
- for_each_present_cpu(cpu) {
+ for_each_cpu(cpu, cpus) {
if (!freq_counters_valid(cpu) ||
freq_inv_set_max_ratio(cpu,
cpufreq_get_hw_max_freq(cpu) * 1000,
arch_timer_get_rate()))
- continue;
-
- cpumask_set_cpu(cpu, valid_cpus);
- enable_policy_freq_counters(cpu, valid_cpus);
+ return;
}
- /* Overwrite amu_fie_cpus if all CPUs support AMU */
- if (cpumask_equal(valid_cpus, cpu_present_mask))
- cpumask_copy(amu_fie_cpus, cpu_present_mask);
-
- if (cpumask_empty(amu_fie_cpus))
- goto free_valid_mask;
+ cpumask_or(amu_fie_cpus, amu_fie_cpus, cpus);
invariant = topology_scale_freq_invariant();
/* We aren't fully invariant yet */
if (!invariant && !cpumask_equal(amu_fie_cpus, cpu_present_mask))
- goto free_valid_mask;
+ return;
static_branch_enable(&amu_fie_key);
- pr_info("CPUs[%*pbl]: counters will be used for FIE.",
- cpumask_pr_args(amu_fie_cpus));
+ pr_debug("CPUs[%*pbl]: counters will be used for FIE.",
+ cpumask_pr_args(cpus));
/*
* Task scheduler behavior depends on frequency invariance support,
*/
if (!invariant)
rebuild_sched_domains_energy();
+}
+
+static int init_amu_fie_callback(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct cpufreq_policy *policy = data;
+
+ if (val == CPUFREQ_CREATE_POLICY)
+ amu_fie_setup(policy->related_cpus);
+
+ /*
+ * We don't need to handle CPUFREQ_REMOVE_POLICY event as the AMU
+ * counters don't have any dependency on cpufreq driver once we have
+ * initialized AMU support and enabled invariance. The AMU counters will
+ * keep on working just fine in the absence of the cpufreq driver, and
+ * for the CPUs for which there are no counters available, the last set
+ * value of freq_scale will remain valid as that is the frequency those
+ * CPUs are running at.
+ */
+
+ return 0;
+}
+
+static struct notifier_block init_amu_fie_notifier = {
+ .notifier_call = init_amu_fie_callback,
+};
+
+static int __init init_amu_fie(void)
+{
+ int ret;
+
+ if (!zalloc_cpumask_var(&amu_fie_cpus, GFP_KERNEL))
+ return -ENOMEM;
-free_valid_mask:
- free_cpumask_var(valid_cpus);
+ ret = cpufreq_register_notifier(&init_amu_fie_notifier,
+ CPUFREQ_POLICY_NOTIFIER);
+ if (ret)
+ free_cpumask_var(amu_fie_cpus);
return ret;
}
-late_initcall_sync(init_amu_fie);
+core_initcall(init_amu_fie);
bool arch_freq_counters_available(const struct cpumask *cpus)
{