[PATCHSET sched_ext/for-7.3-fixes] sched_ext: Sync tools headers from the scx repo

[Tejun Heo]

Hello,

The scx repo carries copies of the tools/sched_ext/include/scx headers
which accumulated fixes and improvements that the kernel copies lack. Sync
them back:

- __COMPAT_read_enum() can now recover 64-bit scx enum values on kernels
  whose BTF lacks BTF_KIND_ENUM64 encoding, backed by a new autogenerated
  enumerator ABI table.

- is_migration_disabled() no longer under-reports for the current task on
  v6.18+ !PREEMPT_RCU kernels where the BPF prolog stopped disabling
  migration.

- The scx_bpf_dsq_peek() version gate and
  scx_bpf_reenqueue_local_from_anywhere() which Gavin and Changwoo posted
  are picked up with the review feedback folded in.

- __COMPAT_scx_bpf_cpu_curr() is restored for schedulers which still run
  on pre-v6.18 kernels, and the rq clock helpers document their stale-read
  behavior on idle CPUs.

This patchset contains the following two patches:

 0001-sched_ext-Sync-tools-autogen-enum-headers-from-the-s.patch
 0002-sched_ext-Sync-common-and-compat-headers-from-the-sc.patch

and is also available in the following git branch:

 git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git scx-tools-header-sync

Based on sched_ext/for-7.3-fixes (5f01293930d1).

 tools/sched_ext/include/scx/common.bpf.h        | 140 ++++++++++++---
 tools/sched_ext/include/scx/compat.bpf.h        |  68 ++++++--
 tools/sched_ext/include/scx/compat.h            |  97 +++++++++++
 tools/sched_ext/include/scx/enum_defs.autogen.h |   5 +-
 tools/sched_ext/include/scx/enums_abi.autogen.h | 223 ++++++++++++++++++++++++
 5 files changed, 501 insertions(+), 32 deletions(-)

Thanks.

-- 
tejun