2 files changed, 16 insertions, 1 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index b66602ad7b33..b7ca5bf9acfc 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -80,6 +80,10 @@ config HOTPLUG_CPU
           can be controlled through /sys/devices/system/cpu/cpu#.
           Say N if you want to disable CPU hotplug.
 
+config DEFAULT_MIGRATION_COST
+        int
+        default "1000000"
+
 config MATHEMU
         bool "IEEE FPU emulation"
         depends on MARCH_G5
diff --git a/kernel/sched.c b/kernel/sched.c
index 66d957227de9..12d291bf3379 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5058,7 +5058,18 @@ static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
 #define MAX_DOMAIN_DISTANCE 32
 
 static unsigned long long migration_cost[MAX_DOMAIN_DISTANCE] =
-                { [ 0 ... MAX_DOMAIN_DISTANCE-1 ] = -1LL };
+                { [ 0 ... MAX_DOMAIN_DISTANCE-1 ] =
+/*
+ * Architectures may override the migration cost and thus avoid
+ * boot-time calibration. Unit is nanoseconds. Mostly useful for
+ * virtualized hardware:
+ */
+#ifdef CONFIG_DEFAULT_MIGRATION_COST
+                        CONFIG_DEFAULT_MIGRATION_COST
+#else
+                        -1LL
+#endif
+};
 
 /*
  * Allow override of migration cost - in units of microseconds.