cpufreq: Simplify userspace governor

Userspace governor has got more code than what it needs for its
functioning, so simplify it.

Portions of code removed are:
 - Extra header files which aren't required anymore (rearrange them
   as well).
 - cpu_{max|min|cur|set}_freq, as they are always the same as
   policy->{max|min|cur}.
 - userspace_cpufreq_notifier_block as we don't need to set
   cpu_cur_freq anymore.
 - cpus_using_userspace_governor as it was for the notifier code.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 12 insertions, 96 deletions

diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
index bbeb9c0720a6..5dc77b7a7594 100644
--- a/drivers/cpufreq/cpufreq_userspace.c
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -13,55 +13,13 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/smp.h>
-#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/interrupt.h>
 #include <linux/cpufreq.h>
-#include <linux/cpu.h>
-#include <linux/types.h>
-#include <linux/fs.h>
-#include <linux/sysfs.h>
+#include <linux/init.h>
+#include <linux/module.h>
 #include <linux/mutex.h>
 
-/**
- * A few values needed by the userspace governor
- */
-static DEFINE_PER_CPU(unsigned int, cpu_max_freq);
-static DEFINE_PER_CPU(unsigned int, cpu_min_freq);
-static DEFINE_PER_CPU(unsigned int, cpu_cur_freq); /* current CPU freq */
-static DEFINE_PER_CPU(unsigned int, cpu_set_freq); /* CPU freq desired by
-                                                        userspace */
 static DEFINE_PER_CPU(unsigned int, cpu_is_managed);
-
 static DEFINE_MUTEX(userspace_mutex);
-static int cpus_using_userspace_governor;
-
-/* keep track of frequency transitions */
-static int
-userspace_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
-        void *data)
-{
-        struct cpufreq_freqs *freq = data;
-
-        if (!per_cpu(cpu_is_managed, freq->cpu))
-                return 0;
-
-        if (val == CPUFREQ_POSTCHANGE) {
-                pr_debug("saving cpu_cur_freq of cpu %u to be %u kHz\n",
-                                freq->cpu, freq->new);
-                per_cpu(cpu_cur_freq, freq->cpu) = freq->new;
-        }
-
-        return 0;
-}
-
-static struct notifier_block userspace_cpufreq_notifier_block = {
-        .notifier_call  = userspace_cpufreq_notifier
-};
-
 
 /**
  * cpufreq_set - set the CPU frequency
@@ -80,13 +38,6 @@ static int cpufreq_set(struct cpufreq_policy *policy, unsigned int freq)
         if (!per_cpu(cpu_is_managed, policy->cpu))
                 goto err;
 
-        per_cpu(cpu_set_freq, policy->cpu) = freq;
-
-        if (freq < per_cpu(cpu_min_freq, policy->cpu))
-                freq = per_cpu(cpu_min_freq, policy->cpu);
-        if (freq > per_cpu(cpu_max_freq, policy->cpu))
-                freq = per_cpu(cpu_max_freq, policy->cpu);
-
         /*
          * We're safe from concurrent calls to ->target() here
          * as we hold the userspace_mutex lock. If we were calling
@@ -107,7 +58,7 @@ static int cpufreq_set(struct cpufreq_policy *policy, unsigned int freq)
 
 static ssize_t show_speed(struct cpufreq_policy *policy, char *buf)
 {
-        return sprintf(buf, "%u\n", per_cpu(cpu_cur_freq, policy->cpu));
+        return sprintf(buf, "%u\n", policy->cur);
 }
 
 static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
@@ -119,66 +70,31 @@ static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
         switch (event) {
         case CPUFREQ_GOV_START:
                 BUG_ON(!policy->cur);
-                mutex_lock(&userspace_mutex);
-
-                if (cpus_using_userspace_governor == 0) {
-                        cpufreq_register_notifier(
-                                        &userspace_cpufreq_notifier_block,
-                                        CPUFREQ_TRANSITION_NOTIFIER);
-                }
-                cpus_using_userspace_governor++;
+                pr_debug("started managing cpu %u\n", cpu);
 
+                mutex_lock(&userspace_mutex);
                 per_cpu(cpu_is_managed, cpu) = 1;
-                per_cpu(cpu_min_freq, cpu) = policy->min;
-                per_cpu(cpu_max_freq, cpu) = policy->max;
-                per_cpu(cpu_cur_freq, cpu) = policy->cur;
-                per_cpu(cpu_set_freq, cpu) = policy->cur;
-                pr_debug("managing cpu %u started "
-                        "(%u - %u kHz, currently %u kHz)\n",
-                                cpu,
-                                per_cpu(cpu_min_freq, cpu),
-                                per_cpu(cpu_max_freq, cpu),
-                                per_cpu(cpu_cur_freq, cpu));
-
                 mutex_unlock(&userspace_mutex);
                 break;
         case CPUFREQ_GOV_STOP:
-                mutex_lock(&userspace_mutex);
-                cpus_using_userspace_governor--;
-                if (cpus_using_userspace_governor == 0) {
-                        cpufreq_unregister_notifier(
-                                        &userspace_cpufreq_notifier_block,
-                                        CPUFREQ_TRANSITION_NOTIFIER);
-                }
+                pr_debug("managing cpu %u stopped\n", cpu);
 
+                mutex_lock(&userspace_mutex);
                 per_cpu(cpu_is_managed, cpu) = 0;
-                per_cpu(cpu_min_freq, cpu) = 0;
-                per_cpu(cpu_max_freq, cpu) = 0;
-                per_cpu(cpu_set_freq, cpu) = 0;
-                pr_debug("managing cpu %u stopped\n", cpu);
                 mutex_unlock(&userspace_mutex);
                 break;
         case CPUFREQ_GOV_LIMITS:
                 mutex_lock(&userspace_mutex);
-                pr_debug("limit event for cpu %u: %u - %u kHz, "
-                        "currently %u kHz, last set to %u kHz\n",
+                pr_debug("limit event for cpu %u: %u - %u kHz, currently %u kHz\n",
                         cpu, policy->min, policy->max,
-                        per_cpu(cpu_cur_freq, cpu),
-                        per_cpu(cpu_set_freq, cpu));
-                if (policy->max < per_cpu(cpu_set_freq, cpu)) {
+                        policy->cur);
+
+                if (policy->max < policy->cur)
                         __cpufreq_driver_target(policy, policy->max,
                                                 CPUFREQ_RELATION_H);
-                } else if (policy->min > per_cpu(cpu_set_freq, cpu)) {
+                else if (policy->min > policy->cur)
                         __cpufreq_driver_target(policy, policy->min,
                                                 CPUFREQ_RELATION_L);
-                } else {
-                        __cpufreq_driver_target(policy,
-                                                per_cpu(cpu_set_freq, cpu),
-                                                CPUFREQ_RELATION_L);
-                }
-                per_cpu(cpu_min_freq, cpu) = policy->min;
-                per_cpu(cpu_max_freq, cpu) = policy->max;
-                per_cpu(cpu_cur_freq, cpu) = policy->cur;
                 mutex_unlock(&userspace_mutex);
                 break;
         }