find_new_ilb

[Julia Lawall]

Starting from the following commit:

commit 45da7a2b0af8fa29dff2e6ba8926322068350fce
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Date:   Tue Aug 18 10:48:17 2020 +0200

    sched/fair: Exclude the current CPU from find_new_ilb()

up through Linux 5.12, I observed that often when most of the machine was
idle, there could be many (thousands) of sched_wake_idle_without_ipi
events, typically between cores 0 and 1.  I don't see this any more in
Linux v5.13-rc1.  I looked through the patches to fair.c and core.c
subsequent to v5.12, and I didn't see anything that explicitly addresses
this issue.  Before I plunge into another set of rounds of bisecting, I
wonder if anyone knows whether and how this problem was resolved?

thanks,
julia