PM: EM: Move CPU capacity check to em_adjust_new_capacity()

Move the check of the CPU capacity currently stored in the energy model
against the arch_scale_cpu_capacity() value to em_adjust_new_capacity()
so it will be done regardless of where the latter is called from.

This will be useful when a new em_adjust_new_capacity() caller is added
subsequently.

While at it, move the pd local variable declaration in
em_check_capacity_update() into the loop in which it is used.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://patch.msgid.link/7810787.EvYhyI6sBW@rjwysocki.net

diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index 4160624..88449d4 100644 (file)
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -725,10 +725,24 @@ free_em_table:
  * Adjustment of CPU performance values after boot, when all CPUs capacites
  * are correctly calculated.
  */
-static void em_adjust_new_capacity(struct device *dev,
+static void em_adjust_new_capacity(unsigned int cpu, struct device *dev,
                                   struct em_perf_domain *pd)
 {
+       unsigned long cpu_capacity = arch_scale_cpu_capacity(cpu);
        struct em_perf_table *em_table;
+       struct em_perf_state *table;
+       unsigned long em_max_perf;
+
+       rcu_read_lock();
+       table = em_perf_state_from_pd(pd);
+       em_max_perf = table[pd->nr_perf_states - 1].performance;
+       rcu_read_unlock();
+
+       if (em_max_perf == cpu_capacity)
+               return;
+
+       pr_debug("updating cpu%d cpu_cap=%lu old capacity=%lu\n", cpu,
+                cpu_capacity, em_max_perf);
 
        em_table = em_table_dup(pd);
        if (!em_table) {
@@ -744,9 +758,6 @@ static void em_adjust_new_capacity(struct device *dev,
 static void em_check_capacity_update(void)
 {
        cpumask_var_t cpu_done_mask;
-       struct em_perf_state *table;
-       struct em_perf_domain *pd;
-       unsigned long cpu_capacity;
        int cpu;
 
        if (!zalloc_cpumask_var(&cpu_done_mask, GFP_KERNEL)) {
@@ -757,7 +768,7 @@ static void em_check_capacity_update(void)
        /* Check if CPUs capacity has changed than update EM */
        for_each_possible_cpu(cpu) {
                struct cpufreq_policy *policy;
-               unsigned long em_max_perf;
+               struct em_perf_domain *pd;
                struct device *dev;
 
                if (cpumask_test_cpu(cpu, cpu_done_mask))
@@ -780,24 +791,7 @@ static void em_check_capacity_update(void)
                cpumask_or(cpu_done_mask, cpu_done_mask,
                           em_span_cpus(pd));
 
-               cpu_capacity = arch_scale_cpu_capacity(cpu);
-
-               rcu_read_lock();
-               table = em_perf_state_from_pd(pd);
-               em_max_perf = table[pd->nr_perf_states - 1].performance;
-               rcu_read_unlock();
-
-               /*
-                * Check if the CPU capacity has been adjusted during boot
-                * and trigger the update for new performance values.
-                */
-               if (em_max_perf == cpu_capacity)
-                       continue;
-
-               pr_debug("updating cpu%d cpu_cap=%lu old capacity=%lu\n",
-                        cpu, cpu_capacity, em_max_perf);
-
-               em_adjust_new_capacity(dev, pd);
+               em_adjust_new_capacity(cpu, dev, pd);
        }
 
        free_cpumask_var(cpu_done_mask);