cpufreq: Add policy create/remove notifiers back

This effectively reverts some changes made by commit f9f41e3ef99
("cpufreq: Remove policy create/remove notifiers").

We have a new use case for policy create/remove notifiers (for
allocating/freeing QoS requests per policy), so add them back.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 8dda62367816f331420eedd58a7c686f0d68a04f..c13dcb59b30cad776f8ede32acaaf79145e29add 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1266,7 +1266,17 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy)
                                   DEV_PM_QOS_MAX_FREQUENCY);
        dev_pm_qos_remove_notifier(dev, &policy->nb_min,
                                   DEV_PM_QOS_MIN_FREQUENCY);
-       dev_pm_qos_remove_request(policy->max_freq_req);
+
+       if (policy->max_freq_req) {
+               /*
+                * CPUFREQ_CREATE_POLICY notification is sent only after
+                * successfully adding max_freq_req request.
+                */
+               blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                                            CPUFREQ_REMOVE_POLICY, policy);
+               dev_pm_qos_remove_request(policy->max_freq_req);
+       }
+
        dev_pm_qos_remove_request(policy->min_freq_req);
        kfree(policy->min_freq_req);
 
@@ -1391,6 +1401,9 @@ static int cpufreq_online(unsigned int cpu)
                                ret);
                        goto out_destroy_policy;
                }
+
+               blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                               CPUFREQ_CREATE_POLICY, policy);
        }
 
        if (cpufreq_driver->get && has_target()) {

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 536a049d7ecccaa11ff7d4ca2c7f21838d7a03e5..afc10384a6817106c65765aad12efc40eb14bd00 100644 (file)
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -458,6 +458,8 @@ static inline void cpufreq_resume(void) {}
 /* Policy Notifiers  */
 #define CPUFREQ_ADJUST                 (0)
 #define CPUFREQ_NOTIFY                 (1)
+#define CPUFREQ_CREATE_POLICY          (2)
+#define CPUFREQ_REMOVE_POLICY          (3)
 
 #ifdef CONFIG_CPU_FREQ
 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);