sched_ext: Remove runtime kfunc mask enforcement

Now that scx_kfunc_context_filter enforces context-sensitive kfunc
restrictions at BPF load time, the per-task runtime enforcement via
scx_kf_mask is redundant. Remove it entirely:

 - Delete enum scx_kf_mask, the kf_mask field on sched_ext_entity, and
   the scx_kf_allow()/scx_kf_disallow()/scx_kf_allowed() helpers along
   with the higher_bits()/highest_bit() helpers they used.
 - Strip the @mask parameter (and the BUILD_BUG_ON checks) from the
   SCX_CALL_OP[_RET]/SCX_CALL_OP_TASK[_RET]/SCX_CALL_OP_2TASKS_RET
   macros and update every call site. Reflow call sites that were
   wrapped only to fit the old 5-arg form and now collapse onto a single
   line under ~100 cols.
 - Remove the in-kfunc scx_kf_allowed() runtime checks from
   scx_dsq_insert_preamble(), scx_dsq_move(), scx_bpf_dispatch_nr_slots(),
   scx_bpf_dispatch_cancel(), scx_bpf_dsq_move_to_local___v2(),
   scx_bpf_sub_dispatch(), scx_bpf_reenqueue_local(), and the per-call
   guard inside select_cpu_from_kfunc().

scx_bpf_task_cgroup() and scx_kf_allowed_on_arg_tasks() were already
cleaned up in the "drop redundant rq-locked check" patch.
scx_kf_allowed_if_unlocked() was rewritten in the preceding "decouple"
patch. No further changes to those helpers here.

Co-developed-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>

0 files changed, 0 insertions, 0 deletions