Merge tag 'wq-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:

 - WQ_PERCPU was added to remaining alloc_workqueue() users and
   system_wq usage was replaced with system_percpu_wq and
   system_unbound_wq with system_dfl_wq.

   These are equivalent conversions with no functional changes,
   preparing for switching default to unbound workqueues from percpu.

 - A handshake mechanism was added for canceling BH workers to avoid
   live lock scenarios under PREEMPT_RT.

 - Unnecessary rcu_read_lock/unlock() calls were dropped in
   wq_watchdog_timer_fn() and workqueue_congested().

 - Documentation was fixed to resolve texinfodocs warnings.

* tag 'wq-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix texinfodocs warning for WQ_* flags reference
  workqueue: WQ_PERCPU added to alloc_workqueue users
  workqueue: replace use of system_wq with system_percpu_wq
  workqueue: replace use of system_unbound_wq with system_dfl_wq
  workqueue: Provide a handshake for canceling BH workers
  workqueue: Remove rcu_read_lock/unlock() in wq_watchdog_timer_fn()
  workqueue: Remove redundant rcu_read_lock/unlock() in workqueue_congested()