cpufreq: acpi-cpufreq: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 297e9128fe9fe11948352f16984a3a85e5e0cdb5..52b25f2356f2326df40de7a0e6c75b26399bd617 100644 (file)
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -536,46 +536,33 @@ static void free_acpi_perf_data(void)
        free_percpu(acpi_perf_data);
 }
 
-static int boost_notify(struct notifier_block *nb, unsigned long action,
-                     void *hcpu)
+static int cpufreq_boost_online(unsigned int cpu)
 {
-       unsigned cpu = (long)hcpu;
        const struct cpumask *cpumask;
 
        cpumask = get_cpu_mask(cpu);
-
        /*
-        * Clear the boost-disable bit on the CPU_DOWN path so that
-        * this cpu cannot block the remaining ones from boosting. On
-        * the CPU_UP path we simply keep the boost-disable flag in
-        * sync with the current global state.
+        * On the CPU_UP path we simply keep the boost-disable flag
+        * in sync with the current global state.
         */
+       boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
+       return 0;
+}
 
-       switch (action) {
-       case CPU_DOWN_FAILED:
-       case CPU_DOWN_FAILED_FROZEN:
-       case CPU_ONLINE:
-       case CPU_ONLINE_FROZEN:
-               boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
-               break;
-
-       case CPU_DOWN_PREPARE:
-       case CPU_DOWN_PREPARE_FROZEN:
-               boost_set_msrs(1, cpumask);
-               break;
+static int cpufreq_boost_down_prep(unsigned int cpu)
+{
+       const struct cpumask *cpumask;
 
-       default:
-               break;
-       }
+       cpumask = get_cpu_mask(cpu);
 
-       return NOTIFY_OK;
+       /*
+        * Clear the boost-disable bit on the CPU_DOWN path so that
+        * this cpu cannot block the remaining ones from boosting.
+        */
+       boost_set_msrs(1, cpumask);
+       return 0;
 }
 
-
-static struct notifier_block boost_nb = {
-       .notifier_call          = boost_notify,
-};
-
 /*
  * acpi_cpufreq_early_init - initialize ACPI P-States library
  *
@@ -922,37 +909,48 @@ static struct cpufreq_driver acpi_cpufreq_driver = {
        .attr           = acpi_cpufreq_attr,
 };
 
+static enum cpuhp_state acpi_cpufreq_online;
+
 static void __init acpi_cpufreq_boost_init(void)
 {
-       if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
-               msrs = msrs_alloc();
-
-               if (!msrs)
-                       return;
+       int ret;
 
-               acpi_cpufreq_driver.set_boost = set_boost;
-               acpi_cpufreq_driver.boost_enabled = boost_state(0);
+       if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)))
+               return;
 
-               cpu_notifier_register_begin();
+       msrs = msrs_alloc();
 
-               /* Force all MSRs to the same value */
-               boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
-                              cpu_online_mask);
+       if (!msrs)
+               return;
 
-               __register_cpu_notifier(&boost_nb);
+       acpi_cpufreq_driver.set_boost = set_boost;
+       acpi_cpufreq_driver.boost_enabled = boost_state(0);
 
-               cpu_notifier_register_done();
+       /*
+        * This calls the online callback on all online cpu and forces all
+        * MSRs to the same value.
+        */
+       ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
+                               cpufreq_boost_online, cpufreq_boost_down_prep);
+       if (ret < 0) {
+               pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
+               msrs_free(msrs);
+               msrs = NULL;
+               return;
        }
+       acpi_cpufreq_online = ret;
 }
 
 static void acpi_cpufreq_boost_exit(void)
 {
-       if (msrs) {
-               unregister_cpu_notifier(&boost_nb);
+       if (!msrs)
+               return;
 
-               msrs_free(msrs);
-               msrs = NULL;
-       }
+       if (acpi_cpufreq_online >= 0)
+               cpuhp_remove_state_nocalls(acpi_cpufreq_online);
+
+       msrs_free(msrs);
+       msrs = NULL;
 }
 
 static int __init acpi_cpufreq_init(void)