This adds two small patches on top of peterz@'s RFC from
https://lore.kernel.org/lkml/20211214204445.665580974@infradead.org/


The new patches are not fully tested - I'm still working on it.
I'll post another patch shortly that adds worker timeouts in
sys_umcg_wait().

Sending this out just to break the silence and to assess if the
approach I'm taking here is not strongly NACKed.


Peter Oskolkov (3):
  sched/umcg: add WF_CURRENT_CPU and externise ttwu
  sched: UMCG: add a blocked worker list
  sched: UMCG: allow to sys_umcg_kick UMCG servers

Peter Zijlstra (2):
  x86/uaccess: Implement unsafe_try_cmpxchg_user()
  sched: User Mode Concurency Groups

 arch/x86/Kconfig                       |   1 +
 arch/x86/entry/syscalls/syscall_64.tbl |   3 +
 arch/x86/include/asm/thread_info.h     |   2 +
 arch/x86/include/asm/uaccess.h         |  57 ++
 fs/exec.c                              |   1 +
 include/linux/entry-common.h           |   6 +
 include/linux/sched.h                  |  86 +++
 include/linux/syscalls.h               |   4 +
 include/linux/thread_info.h            |   2 +
 include/uapi/asm-generic/unistd.h      |   9 +-
 include/uapi/linux/umcg.h              | 161 +++++
 init/Kconfig                           |  15 +
 kernel/entry/common.c                  |  18 +-
 kernel/exit.c                          |   5 +
 kernel/sched/Makefile                  |   1 +
 kernel/sched/core.c                    |  12 +-
 kernel/sched/fair.c                    |   4 +
 kernel/sched/sched.h                   |  15 +-
 kernel/sched/umcg.c                    | 913 +++++++++++++++++++++++++
 kernel/sys_ni.c                        |   5 +
 20 files changed, 1305 insertions(+), 15 deletions(-)
 create mode 100644 include/uapi/linux/umcg.h
 create mode 100644 kernel/sched/umcg.c


base-commit: 85538cc07d6b6dcffc1df64a22308fcb05ecddf4
-- 
2.34.1.703.g22d0c6ccf7-goog