| * HMP scheduler |
| |
| This file describes the bindings for an optional HMP scheduler |
| node (/sched-hmp). |
| |
| Required properties: |
| |
| Optional properties: |
| |
| - boost-policy: The HMP scheduler has two types of task placement boost |
| policies. |
| |
| (1) boost-on-big policy make use of all big CPUs up to their full capacity |
| before using the little CPUs. This improves performance on true b.L systems |
| where the big CPUs have higher efficiency compared to the little CPUs. |
| |
| (2) boost-on-all policy place the tasks on the CPU having the highest |
| spare capacity. This policy is optimal for SMP like systems. |
| |
| The scheduler sets the boost policy to boost-on-big on systems which has |
| CPUs of different efficiencies. However it is possible that CPUs of the |
| same micro architecture to have slight difference in efficiency due to |
| other factors like cache size. Selecting the boost-on-big policy based |
| on relative difference in efficiency is not optimal on such systems. |
| The boost-policy device tree property is introduced to specify the |
| required boost type and it overrides the default selection of boost |
| type in the scheduler. |
| |
| The possible values for this property are "boost-on-big" and "boost-on-all". |
| |
| Example: |
| |
| sched-hmp { |
| boost-policy = "boost-on-all" |
| } |