Merge tag 'lkmm.2023.04.07a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull Linux Kernel Memory Model updates from Paul McKenney
 "This improves LKMM diagnostic messages, unifies handling of the
  ordering produced by unlock/lock pairs, adds support for the
  smp_mb__after_srcu_read_unlock() macro, removes redundant members from
  the to-r relation, brings SRCU read-side semantics into alignment with
  Linux-kernel SRCU, makes ppo a subrelation of po, and improves
  documentation"

* tag 'lkmm.2023.04.07a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
  Documentation: litmus-tests: Correct spelling
  tools/memory-model: Add documentation about SRCU read-side critical sections
  tools/memory-model: Make ppo a subrelation of po
  tools/memory-model: Provide exact SRCU semantics
  tools/memory-model: Restrict to-r to read-read address dependency
  tools/memory-model: Add smp_mb__after_srcu_read_unlock()
  tools/memory-model: Unify UNLOCK+LOCK pairings to po-unlock-lock-po
  tools/memory-model: Update some warning labels