cpufreq: stats: Make the stats code non-modular

[cascardo/linux.git] / include / linux / cpufreq.h

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 718e872..7ed93c3 100644 (file)
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -102,6 +102,17 @@ struct cpufreq_policy {
         */
        struct rw_semaphore     rwsem;
 
+       /*
+        * Fast switch flags:
+        * - fast_switch_possible should be set by the driver if it can
+        *   guarantee that frequency can be changed on any CPU sharing the
+        *   policy and that the change will affect all of the policy CPUs then.
+        * - fast_switch_enabled is to be set by governors that support fast
+        *   freqnency switching with the help of cpufreq_enable_fast_switch().
+        */
+       bool                    fast_switch_possible;
+       bool                    fast_switch_enabled;
+
        /* Synchronization for frequency transitions */
        bool                    transition_ongoing; /* Tracks transition status */
        spinlock_t              transition_lock;
@@ -156,6 +167,8 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
 int cpufreq_update_policy(unsigned int cpu);
 bool have_governor_per_policy(void);
 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
+void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
+void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
 #else
 static inline unsigned int cpufreq_get(unsigned int cpu)
 {
@@ -172,6 +185,18 @@ static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
 static inline void disable_cpufreq(void) { }
 #endif
 
+#ifdef CONFIG_CPU_FREQ_STAT
+void cpufreq_stats_create_table(struct cpufreq_policy *policy);
+void cpufreq_stats_free_table(struct cpufreq_policy *policy);
+void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
+                                    unsigned int new_freq);
+#else
+static inline void cpufreq_stats_create_table(struct cpufreq_policy *policy) { }
+static inline void cpufreq_stats_free_table(struct cpufreq_policy *policy) { }
+static inline void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
+                                                  unsigned int new_freq) { }
+#endif /* CONFIG_CPU_FREQ_STAT */
+
 /*********************************************************************
  *                      CPUFREQ DRIVER INTERFACE                     *
  *********************************************************************/
@@ -236,6 +261,8 @@ struct cpufreq_driver {
                                  unsigned int relation);       /* Deprecated */
        int             (*target_index)(struct cpufreq_policy *policy,
                                        unsigned int index);
+       unsigned int    (*fast_switch)(struct cpufreq_policy *policy,
+                                      unsigned int target_freq);
        /*
         * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION
         * unset.
@@ -426,18 +453,27 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
 #define CPUFREQ_POLICY_POWERSAVE       (1)
 #define CPUFREQ_POLICY_PERFORMANCE     (2)
 
-/* Governor Events */
-#define CPUFREQ_GOV_START      1
-#define CPUFREQ_GOV_STOP       2
-#define CPUFREQ_GOV_LIMITS     3
-#define CPUFREQ_GOV_POLICY_INIT        4
-#define CPUFREQ_GOV_POLICY_EXIT        5
+/*
+ * The polling frequency depends on the capability of the processor. Default
+ * polling frequency is 1000 times the transition latency of the processor. The
+ * ondemand governor will work on any processor with transition latency <= 10ms,
+ * using appropriate sampling rate.
+ *
+ * For CPUs with transition latency > 10ms (mostly drivers with CPUFREQ_ETERNAL)
+ * the ondemand governor will not work. All times here are in us (microseconds).
+ */
+#define MIN_SAMPLING_RATE_RATIO                (2)
+#define LATENCY_MULTIPLIER             (1000)
+#define MIN_LATENCY_MULTIPLIER         (20)
+#define TRANSITION_LATENCY_LIMIT       (10 * 1000 * 1000)
 
 struct cpufreq_governor {
        char    name[CPUFREQ_NAME_LEN];
-       int     initialized;
-       int     (*governor)     (struct cpufreq_policy *policy,
-                                unsigned int event);
+       int     (*init)(struct cpufreq_policy *policy);
+       void    (*exit)(struct cpufreq_policy *policy);
+       int     (*start)(struct cpufreq_policy *policy);
+       void    (*stop)(struct cpufreq_policy *policy);
+       void    (*limits)(struct cpufreq_policy *policy);
        ssize_t (*show_setspeed)        (struct cpufreq_policy *policy,
                                         char *buf);
        int     (*store_setspeed)       (struct cpufreq_policy *policy,
@@ -450,6 +486,8 @@ struct cpufreq_governor {
 };
 
 /* Pass a target to the cpufreq driver */
+unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
+                                       unsigned int target_freq);
 int cpufreq_driver_target(struct cpufreq_policy *policy,
                                 unsigned int target_freq,
                                 unsigned int relation);
@@ -462,6 +500,37 @@ void cpufreq_unregister_governor(struct cpufreq_governor *governor);
 struct cpufreq_governor *cpufreq_default_governor(void);
 struct cpufreq_governor *cpufreq_fallback_governor(void);
 
+static inline void cpufreq_policy_apply_limits(struct cpufreq_policy *policy)
+{
+       if (policy->max < policy->cur)
+               __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
+       else if (policy->min > policy->cur)
+               __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
+}
+
+/* Governor attribute set */
+struct gov_attr_set {
+       struct kobject kobj;
+       struct list_head policy_list;
+       struct mutex update_lock;
+       int usage_count;
+};
+
+/* sysfs ops for cpufreq governors */
+extern const struct sysfs_ops governor_sysfs_ops;
+
+void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node);
+void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node);
+unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node);
+
+/* Governor sysfs attribute */
+struct governor_attr {
+       struct attribute attr;
+       ssize_t (*show)(struct gov_attr_set *attr_set, char *buf);
+       ssize_t (*store)(struct gov_attr_set *attr_set, const char *buf,
+                        size_t count);
+};
+
 /*********************************************************************
  *                     FREQUENCY TABLE HELPERS                       *
  *********************************************************************/