Re: [PATCH v2 sched_ext/for-7.4] sched_ext: Queue the kick_sync wait from set_next_task_scx()

[Tejun Heo]

Applied to sched_ext/for-7.4-fixes.

A few follow-ups:

- With proxy exec, __schedule() can call set_next_task() twice on a
  repicked donor (SNT_REPICK, then SNT_PICK), which queues
  kick_sync_bal_cb twice. When it's alone on the list, it ends up linked
  to itself and the wait runs twice.

- The foreign CPU check in kick_sync_wait_bal_cb() looks unreachable now.

- Not from this patch, but maybe_queue_balance_callback() clears
  SCX_RQ_BAL_CB_PENDING when queueing, so a proxy exec zap leaves the
  deferred work unscheduled until the next wakeup or deferred request on
  the CPU.

Thanks.

--
tejun