1 files changed, 18 insertions, 26 deletions

diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 7a74d175287b..06bfe1c572cd 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -42,27 +42,12 @@
  * this governor will not work.
  * All times here are in uS.
  */
-static unsigned int def_sampling_rate;
 #define MIN_SAMPLING_RATE_RATIO                 (2)
-/* for correct statistics, we need at least 10 ticks between each measure */
-#define MIN_STAT_SAMPLING_RATE                  \
-                        (MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10))
-#define MIN_SAMPLING_RATE                       \
-                        (def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
-/* Above MIN_SAMPLING_RATE will vanish with its sysfs file soon
- * Define the minimal settable sampling rate to the greater of:
- *   - "HW transition latency" * 100 (same as default sampling / 10)
- *   - MIN_STAT_SAMPLING_RATE
- * To avoid that userspace shoots itself.
-*/
-static unsigned int minimum_sampling_rate(void)
-{
-        return max(def_sampling_rate / 10, MIN_STAT_SAMPLING_RATE);
-}
 
-/* This will also vanish soon with removing sampling_rate_max */
-#define MAX_SAMPLING_RATE                       (500 * def_sampling_rate)
+static unsigned int min_sampling_rate;
+
 #define LATENCY_MULTIPLIER                      (1000)
+#define MIN_LATENCY_MULTIPLIER                  (100)
 #define DEF_SAMPLING_DOWN_FACTOR                (1)
 #define MAX_SAMPLING_DOWN_FACTOR                (10)
 #define TRANSITION_LATENCY_LIMIT                (10 * 1000 * 1000)
@@ -190,7 +175,7 @@ static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
                        current->comm);
                 print_once = 1;
         }
-        return sprintf(buf, "%u\n", MAX_SAMPLING_RATE);
+        return sprintf(buf, "%u\n", -1U);
 }
 
 static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
@@ -202,7 +187,7 @@ static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
                        "sysfs file is deprecated - used by: %s\n", current->comm);
                 print_once = 1;
         }
-        return sprintf(buf, "%u\n", MIN_SAMPLING_RATE);
+        return sprintf(buf, "%u\n", min_sampling_rate);
 }
 
 #define define_one_ro(_name)            \
@@ -254,7 +239,7 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
                 return -EINVAL;
 
         mutex_lock(&dbs_mutex);
-        dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate());
+        dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate);
         mutex_unlock(&dbs_mutex);
 
         return count;
@@ -601,11 +586,18 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
                         if (latency == 0)
                                 latency = 1;
 
-                        def_sampling_rate =
-                                max(latency * LATENCY_MULTIPLIER,
-                                    MIN_STAT_SAMPLING_RATE);
-
-                        dbs_tuners_ins.sampling_rate = def_sampling_rate;
+                        /*
+                         * conservative does not implement micro like ondemand
+                         * governor, thus we are bound to jiffes/HZ
+                         */
+                        min_sampling_rate =
+                                MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10);
+                        /* Bring kernel and HW constraints together */
+                        min_sampling_rate = max(min_sampling_rate,
+                                        MIN_LATENCY_MULTIPLIER * latency);
+                        dbs_tuners_ins.sampling_rate =
+                                max(min_sampling_rate,
+                                    latency * LATENCY_MULTIPLIER);
 
                         cpufreq_register_notifier(
                                         &dbs_cpufreq_notifier_block,