[CPUFREQ] [1/2] add __find_governor helper and clean up some error handling.

Adds a __find_governor() helper function to look up a governor by
name.  Also restructures some error handling to conform to the
"single-exit" model which is generally preferred for kernel code.

Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 34 insertions, 23 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index ad996c772c8b..9b416372a8e4 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -284,39 +284,52 @@ EXPORT_SYMBOL_GPL(cpufreq_notify_transition);
  *                          SYSFS INTERFACE                          *
  *********************************************************************/
 
+static struct cpufreq_governor *__find_governor(const char *str_governor)
+{
+        struct cpufreq_governor *t;
+
+        list_for_each_entry(t, &cpufreq_governor_list, governor_list)
+                if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN))
+                        return t;
+
+        return NULL;
+}
+
 /**
  * cpufreq_parse_governor - parse a governor string
  */
 static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
                                 struct cpufreq_governor **governor)
 {
+        int err = -EINVAL;
+
         if (!cpufreq_driver)
-                return -EINVAL;
+                goto out;
+
         if (cpufreq_driver->setpolicy) {
                 if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
                         *policy = CPUFREQ_POLICY_PERFORMANCE;
-                        return 0;
+                        err = 0;
                 } else if (!strnicmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
                         *policy = CPUFREQ_POLICY_POWERSAVE;
-                        return 0;
+                        err = 0;
                 }
-                return -EINVAL;
-        } else {
+        } else if (cpufreq_driver->target) {
                 struct cpufreq_governor *t;
+
                 mutex_lock(&cpufreq_governor_mutex);
-                if (!cpufreq_driver || !cpufreq_driver->target)
-                        goto out;
-                list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
-                        if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN)) {
-                                *governor = t;
-                                mutex_unlock(&cpufreq_governor_mutex);
-                                return 0;
-                        }
+
+                t = __find_governor(str_governor);
+
+                if (t != NULL) {
+                        *governor = t;
+                        err = 0;
                 }
-out:
+
                 mutex_unlock(&cpufreq_governor_mutex);
         }
-        return -EINVAL;
+  out:
+        return err;
 }
 
 
@@ -1265,23 +1278,21 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
 
 int cpufreq_register_governor(struct cpufreq_governor *governor)
 {
-        struct cpufreq_governor *t;
+        int err;
 
         if (!governor)
                 return -EINVAL;
 
         mutex_lock(&cpufreq_governor_mutex);
 
-        list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
-                if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) {
-                        mutex_unlock(&cpufreq_governor_mutex);
-                        return -EBUSY;
-                }
+        err = -EBUSY;
+        if (__find_governor(governor->name) == NULL) {
+                err = 0;
+                list_add(&governor->governor_list, &cpufreq_governor_list);
         }
-        list_add(&governor->governor_list, &cpufreq_governor_list);
 
         mutex_unlock(&cpufreq_governor_mutex);
-        return 0;
+        return err;
 }
 EXPORT_SYMBOL_GPL(cpufreq_register_governor);