2 files changed, 25 insertions, 3 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 1210fb0e45ff..a96726658eca 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -763,6 +763,17 @@ enum cpu_idle_type {
 #define SD_SERIALIZE            1024    /* Only a single load balancing instance */
 #define SD_WAKE_IDLE_FAR        2048    /* Gain latency sacrificing cache hit */
 
+enum powersavings_balance_level {
+        POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
+        POWERSAVINGS_BALANCE_BASIC,     /* Fill one thread/core/package
+                                         * first for long running threads
+                                         */
+        POWERSAVINGS_BALANCE_WAKEUP,    /* Also bias task wakeups to semi-idle
+                                         * cpu package for power savings
+                                         */
+        MAX_POWERSAVINGS_BALANCE_LEVELS
+};
+
 extern int sched_mc_power_savings, sched_smt_power_savings;
 
 static inline int sd_balance_for_mc_power(void)
diff --git a/kernel/sched.c b/kernel/sched.c
index b309027bf9e8..56b285cd5350 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -7906,14 +7906,25 @@ int arch_reinit_sched_domains(void)
 static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
 {
         int ret;
+        unsigned int level = 0;
 
-        if (buf[0] != '0' && buf[0] != '1')
+        if (sscanf(buf, "%u", &level) != 1)
+                return -EINVAL;
+
+        /*
+         * level is always be positive so don't check for
+         * level < POWERSAVINGS_BALANCE_NONE which is 0
+         * What happens on 0 or 1 byte write,
+         * need to check for count as well?
+         */
+
+        if (level >= MAX_POWERSAVINGS_BALANCE_LEVELS)
                 return -EINVAL;
 
         if (smt)
-                sched_smt_power_savings = (buf[0] == '1');
+                sched_smt_power_savings = level;
         else
-                sched_mc_power_savings = (buf[0] == '1');
+                sched_mc_power_savings = level;
 
         ret = arch_reinit_sched_domains();