[PATCH 1/2] powerpc/vcpu: Assume dedicated processors as non-preempt

[Srikar Dronamraju]

* Srikar Dronamraju <srikar at linux.vnet.ibm.com> [2019-12-04 19:14:58]:

> 
> 
>   # perf stat -a -r 5 ./schbench
> v5.4				                v5.4 + patch
> Latency percentiles (usec)                      Latency percentiles (usec)
> 	49.0000th: 47                           	50.0000th: 33
> 	74.0000th: 64                           	75.0000th: 44
> 	89.0000th: 76                           	90.0000th: 50
> 	94.0000th: 83                           	95.0000th: 53
> 	*98.0000th: 103                         	*99.0000th: 57
> 	98.5000th: 2124                         	99.5000th: 59
> 	98.9000th: 7976                         	99.9000th: 83
> 	min=-1, max=10519                       	min=0, max=117
> Latency percentiles (usec)                      Latency percentiles (usec)
> 	49.0000th: 45                           	50.0000th: 34
> 	74.0000th: 61                           	75.0000th: 45
> 	89.0000th: 70                           	90.0000th: 52
> 	94.0000th: 77                           	95.0000th: 56
> 	*98.0000th: 504                         	*99.0000th: 62
> 	98.5000th: 4012                         	99.5000th: 64
> 	98.9000th: 8168                         	99.9000th: 79
> 	min=-1, max=14500                       	min=0, max=123
> Latency percentiles (usec)                      Latency percentiles (usec)
> 	49.0000th: 48                           	50.0000th: 35
> 	74.0000th: 65                           	75.0000th: 47
> 	89.0000th: 76                           	90.0000th: 55
> 	94.0000th: 82                           	95.0000th: 59
> 	*98.0000th: 1098                        	*99.0000th: 67
> 	98.5000th: 3988                         	99.5000th: 71
> 	98.9000th: 9360                         	99.9000th: 98
> 	min=-1, max=19283                       	min=0, max=137
> Latency percentiles (usec)                      Latency percentiles (usec)
> 	49.0000th: 46                           	50.0000th: 35
> 	74.0000th: 63                           	75.0000th: 46
> 	89.0000th: 73                           	90.0000th: 53
> 	94.0000th: 78                           	95.0000th: 57
> 	*98.0000th: 113                         	*99.0000th: 63
> 	98.5000th: 2316                         	99.5000th: 65
> 	98.9000th: 7704                         	99.9000th: 83
> 	min=-1, max=17976                       	min=0, max=139
> Latency percentiles (usec)                      Latency percentiles (usec)
> 	49.0000th: 46                           	50.0000th: 34
> 	74.0000th: 62                           	75.0000th: 46
> 	89.0000th: 73                           	90.0000th: 53
> 	94.0000th: 79                           	95.0000th: 57
> 	*98.0000th: 97                          	*99.0000th: 64
> 	98.5000th: 1398                         	99.5000th: 70
> 	98.9000th: 8136                         	99.9000th: 100
> 	min=-1, max=10008                       	min=0, max=142
> 

Just to be clear, since these are latency values, lesser number is better.

-- 
Thanks and Regards
Srikar Dronamraju