Re: [PATCH v2 04/13] sched: Introduce SD_ASYM_CPUCAPACITY sched_domain topology flag

[Peter Zijlstra]

On Wed, Jun 22, 2016 at 06:03:15PM +0100, Morten Rasmussen wrote:
> Add a topology flag to the sched_domain hierarchy indicating
> sched_groups at this sched_domain level having different per cpu
> capacity (e.g. big.LITTLE big-only and little-only groups) or groups in
> sibling domains with different capacity.

>                                          IOW, domains not spanning cpus
> of all available capacities up until and including the first level
> spanning cpus of all capacities available system wide.

This ^, which would be SD1 below, why? I would expect only SD2 to be
tagged, since that does indeed have asymmetric capacities.

> 
> SD 2      [  0      1      2      3]  SD_ASYM_CPUCAPACITY
> 
> SD 1      [  0      1] [   2      3]  SD_ASYM_CPUCAPACITY
>
> cpu:         0      1      2      3
> capacity:  756    756   1024   1024
>