[GIT PULL] scheduler fixes

[Ingo Molnar]

Linus,

Please pull the latest sched/urgent Git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-urgent-2026-02-07

for you to fetch changes up to 4463c7aa11a6e67169ae48c6804968960c4bffea:

Miscellaneous MMCID fixes to address bugs and
performance regressions in the recent rewrite
of the SCHED_MM_CID management code:

 - Fix livelock triggered by BPF CI testing

 - Fix hard lockup on weakly ordered systems

 - Simplify the dropping of CIDs in the exit path
   by removing an unintended transition phase.

 - Fix performance/scalability regression on a
   thread-pool benchmark by optimizing transitional
   CIDs when scheduling out.

[ MERGE NOTE: these changes are bigger than what would be ideal
              for a late -rc8 merge, but I don't think
              a good case can be made to delay these fixes.
              Feel free to overrule. ]
 Thanks,

	Ingo

------------------>
Thomas Gleixner (4):
      sched/mmcid: Prevent live lock on task to CPU mode transition
      sched/mmcid: Protect transition on weakly ordered systems
      sched/mmcid: Drop per CPU CID immediately when switching to per task mode
      sched/mmcid: Optimize transitional CIDs when scheduling out


 include/linux/rseq_types.h |   6 +-
 kernel/sched/core.c        | 184 +++++++++++++++++++++++++++++++--------------
 kernel/sched/sched.h       |  44 ++++++++---
 3 files changed, 163 insertions(+), 71 deletions(-)