s390/hiperdispatch: Decrease steal time threshold

Higher steal time thresholds favor low utilization scenarios, which is not
the common case for s390. Set steal time threshold to a lower value to
prioritize vertical high and medium CPUs sooner and allow high utilization
scenarios to benefit from it.

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

Author: NickJackolson

arch/s390/kernel/hiperdispatch.c

@@ -65,7 +65,7 @@
 
 #define HD_DELAY_FACTOR			(4)
 #define HD_DELAY_INTERVAL		(HZ / 4)
-#define HD_STEAL_THRESHOLD		30
+#define HD_STEAL_THRESHOLD		10
 #define HD_STEAL_AVG_WEIGHT		16
 
 static cpumask_t hd_vl_coremask;	/* Mask containing all vertical low COREs */