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>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 4b14f04daa41f..6cbc846e39816 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -385,8 +385,8 @@ static struct policy_dbs_info *alloc_policy_dbs_info(struct cpufreq_policy *poli
 	struct policy_dbs_info *policy_dbs;
 	int j;
 
-	/* Allocate memory for the common information for policy->cpus */
-	policy_dbs = kzalloc(sizeof(*policy_dbs), GFP_KERNEL);
+	/* Allocate memory for per-policy governor data. */
+	policy_dbs = gov->alloc();
 	if (!policy_dbs)
 		return NULL;
 
@@ -421,7 +421,7 @@ static void free_policy_dbs_info(struct cpufreq_policy *policy,
 		j_cdbs->policy_dbs = NULL;
 		j_cdbs->update_util.func = NULL;
 	}
-	kfree(policy_dbs);
+	gov->free(policy_dbs);
 }
 
 static int cpufreq_governor_init(struct cpufreq_policy *policy)
@@ -582,7 +582,6 @@ static int cpufreq_governor_start(struct cpufreq_policy *policy)
 static int cpufreq_governor_stop(struct cpufreq_policy *policy)
 {
 	gov_cancel_work(policy);
-
 	return 0;
 }