diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/scheduler/sched-energy.rst | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/Documentation/scheduler/sched-energy.rst b/Documentation/scheduler/sched-energy.rst index 9580c57a52bc..78f850778982 100644 --- a/Documentation/scheduler/sched-energy.rst +++ b/Documentation/scheduler/sched-energy.rst @@ -331,16 +331,8 @@ asymmetric CPU topologies for now. This requirement is checked at run-time by looking for the presence of the SD_ASYM_CPUCAPACITY flag when the scheduling domains are built. -The flag is set/cleared automatically by the scheduler topology code whenever -there are CPUs with different capacities in a root domain. The capacities of -CPUs are provided by arch-specific code through the arch_scale_cpu_capacity() -callback. As an example, arm and arm64 share an implementation of this callback -which uses a combination of CPUFreq data and device-tree bindings to compute the -capacity of CPUs (see drivers/base/arch_topology.c for more details). - -So, in order to use EAS on your platform your architecture must implement the -arch_scale_cpu_capacity() callback, and some of the CPUs must have a lower -capacity than others. +See Documentation/sched/sched-capacity.rst for requirements to be met for this +flag to be set in the sched_domain hierarchy. Please note that EAS is not fundamentally incompatible with SMP, but no significant savings on SMP platforms have been observed yet. This restriction |