cpufreq: governor: Make governor private data per-policy

Some fields in struct od_cpu_dbs_info_s and struct cs_cpu_dbs_info_s
are only used for a limited set of CPUs.  Namely, if a policy is
shared between multiple CPUs, those fields will only be used for one
of them (policy->cpu).  This means that they really are per-policy
rather than per-CPU and holding room for them in per-CPU data
structures is generally wasteful.  Also moving those fields into
per-policy data structures will allow some significant simplifications
to be made going forward.

For this reason, introduce struct cs_policy_dbs_info and
struct od_policy_dbs_info to hold those fields.  Define each of the
new structures as an extension of struct policy_dbs_info (such that
struct policy_dbs_info is embedded in each of them) and introduce
new ->alloc and ->free governor callbacks to allocate and free
those structures, respectively, such that ->alloc() will return
a pointer to the struct policy_dbs_info embedded in the allocated
data structure and ->free() will take that pointer as its argument.

With that, modify the code accessing the data fields in question
in per-CPU data objects to look for them in the new structures
via the struct policy_dbs_info pointer available to it and drop
them from struct od_cpu_dbs_info_s and struct cs_cpu_dbs_info_s.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
index 5c7d1ea..354e0d3 100644
--- a/drivers/cpufreq/cpufreq_governor.h
+++ b/drivers/cpufreq/cpufreq_governor.h
@@ -157,17 +157,10 @@
 
 struct od_cpu_dbs_info_s {
 	struct cpu_dbs_info cdbs;
-	struct cpufreq_frequency_table *freq_table;
-	unsigned int freq_lo;
-	unsigned int freq_lo_delay_us;
-	unsigned int freq_hi_delay_us;
-	unsigned int sample_type:1;
 };
 
 struct cs_cpu_dbs_info_s {
 	struct cpu_dbs_info cdbs;
-	unsigned int down_skip;
-	unsigned int requested_freq;
 };
 
 /* Per policy Governors sysfs tunables */
@@ -193,6 +186,8 @@
 
 	struct cpu_dbs_info *(*get_cpu_cdbs)(int cpu);
 	unsigned int (*gov_dbs_timer)(struct cpufreq_policy *policy);
+	struct policy_dbs_info *(*alloc)(void);
+	void (*free)(struct policy_dbs_info *policy_dbs);
 	int (*init)(struct dbs_data *dbs_data, bool notify);
 	void (*exit)(struct dbs_data *dbs_data, bool notify);
 	void (*start)(struct cpufreq_policy *policy);