Re: [PATCH v3 0/8] sched/topology: Optimize sd->shared allocation

[Peter Zijlstra]

On Tue, Jan 20, 2026 at 11:32:38AM +0000, K Prateek Nayak wrote:

> "sd->shared" is only allocated for the topmost SD_SHARE_LLC domain and
> the topology layer uses the sched domain degeneration path to pass the
> reference to the final "sd_llc" domain. 

I'm fairly sure we've had patches that introduced it for other levels at
various times, but clearly none of those ever made it.

Anyway, a quick peek seems to suggest it is still easy to extend.


>  include/linux/sched/topology.h |   1 -
>  kernel/sched/fair.c            |  62 +++++++-----------
>  kernel/sched/sched.h           |   2 +-
>  kernel/sched/topology.c        | 111 ++++++++++++++++++++++-----------
>  4 files changed, 101 insertions(+), 75 deletions(-)

Is this really worth the extra lines though?