[GIT PULL] sched_ext: Changes for v6.20

[Tejun Heo]

Hi, Linus.

The following changes since commit ccaeeb585c7c2a0ac67ee1af9acb4d1411dc409e:

  sched_ext: Use the resched_cpu() to replace resched_curr() in the bypass_lb_node() (2025-12-22 17:51:51 -1000)

are available in the Git repository at:

  https://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git tags/sched_ext-for-6.20

for you to fetch changes up to 4544e9c4ec9a5955a37fdd8204a3d98106f97ab7:

  selftests/sched_ext: Fix init_enable_count flakiness (2026-02-02 09:45:09 -1000)

----------------------------------------------------------------
sched_ext: Changes for v6.20

- Move C example schedulers back from the external scx repo to
  tools/sched_ext as the authoritative source. scx_userland and scx_pair
  are returning while scx_sdt (BPF arena-based task data management) is
  new. These schedulers will be dropped from the external repo.

- Improve error reporting by adding scx_bpf_error() calls when DSQ
  creation fails across all in-tree schedulers.

- Avoid redundant irq_work_queue() calls in destroy_dsq() by only
  queueing when llist_add() indicates an empty list.

- Fix flaky init_enable_count selftest by properly synchronizing
  pre-forked children using a pipe instead of sleep().

----------------------------------------------------------------
Emil Tsalapatis (4):
      tools/sched_ext: add scx_userland scheduler
      tools/sched_ext: add scx_pair scheduler
      tools/sched_ext: add arena based scheduler
      tools/sched_ext: Fix data header access during free in scx_sdt

George Guo (1):
      sched_ext: Add error logging for dsq creation failures

Tejun Heo (1):
      selftests/sched_ext: Fix init_enable_count flakiness

Zqiang (1):
      sched_ext: Avoid multiple irq_work_queue() calls in destroy_dsq()

zhidao su (1):
      tools/sched_ext: Add error logging for dsq creation failures in remaining schedulers

 kernel/sched/ext.c                                 |   4 +-
 tools/sched_ext/Makefile                           |   2 +-
 tools/sched_ext/scx_central.bpf.c                  |   4 +-
 tools/sched_ext/scx_cpu0.bpf.c                     |  10 +-
 tools/sched_ext/scx_flatcg.bpf.c                   |  14 +-
 tools/sched_ext/scx_pair.bpf.c                     | 610 ++++++++++++++++++
 tools/sched_ext/scx_pair.c                         | 180 ++++++
 tools/sched_ext/scx_pair.h                         |   9 +
 tools/sched_ext/scx_qmap.bpf.c                     |   8 +-
 tools/sched_ext/scx_sdt.bpf.c                      | 716 +++++++++++++++++++++
 tools/sched_ext/scx_sdt.c                          | 101 +++
 tools/sched_ext/scx_sdt.h                          | 113 ++++
 tools/sched_ext/scx_simple.bpf.c                   |  10 +-
 tools/sched_ext/scx_userland.bpf.c                 | 344 ++++++++++
 tools/sched_ext/scx_userland.c                     | 437 +++++++++++++
 tools/sched_ext/scx_userland.h                     |  17 +
 .../selftests/sched_ext/init_enable_count.c        |  34 +-
 17 files changed, 2592 insertions(+), 21 deletions(-)
 create mode 100644 tools/sched_ext/scx_pair.bpf.c
 create mode 100644 tools/sched_ext/scx_pair.c
 create mode 100644 tools/sched_ext/scx_pair.h
 create mode 100644 tools/sched_ext/scx_sdt.bpf.c
 create mode 100644 tools/sched_ext/scx_sdt.c
 create mode 100644 tools/sched_ext/scx_sdt.h
 create mode 100644 tools/sched_ext/scx_userland.bpf.c
 create mode 100644 tools/sched_ext/scx_userland.c
 create mode 100644 tools/sched_ext/scx_userland.h

--
tejun