[PATCH v2 00/12] sched: Address schbench regression

[Peter Zijlstra]

Hi!

Previous version:

  https://lkml.kernel.org/r/20250520094538.086709102@xxxxxxxxxxxxx


Changes:
 - keep dl_server_stop(), just remove the 'normal' usage of it (juril)
 - have the sched_delayed wake list IPIs do select_task_rq() (vingu)
 - fixed lockdep splat (dietmar)
 - added a few preperatory patches


Patches apply on top of tip/master (which includes the disabling of private futex)
and clm's newidle balance patch (which I'm awaiting vingu's ack on).

Performance is similar to the last version; as tested on my SPR on v6.15 base:

v6.15:
schbench-6.15.0-1.txt:average rps: 2891403.72
schbench-6.15.0-2.txt:average rps: 2889997.02
schbench-6.15.0-3.txt:average rps: 2894745.17

v6.15 + patches 1-10:
schbench-6.15.0-dirty-4.txt:average rps: 3038265.95
schbench-6.15.0-dirty-5.txt:average rps: 3037327.50
schbench-6.15.0-dirty-6.txt:average rps: 3038160.15

v6.15 + all patches:
schbench-6.15.0-dirty-deferred-1.txt:average rps: 3043404.30
schbench-6.15.0-dirty-deferred-2.txt:average rps: 3046124.17
schbench-6.15.0-dirty-deferred-3.txt:average rps: 3043627.10


Patches can also be had here:

  git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git sched/core


I'm hoping we can get this merged for next cycle so we can all move on from this.