kernel/rcu/tree.c

4381 	unsigned long gseq = READ_ONCE(rcu_state.barrier_sequence);
4387 	if (rcu_seq_state(lseq) || !rcu_seq_state(gseq) || rcu_seq_ctr(lseq) != rcu_seq_ctr(gseq))
4410 	smp_store_release(&rdp->barrier_seq_snap, gseq);
4441 	unsigned long gseq;
4461 	gseq = rcu_state.barrier_sequence;
4483 		if (smp_load_acquire(&rdp->barrier_seq_snap) == gseq)
4487 			WRITE_ONCE(rdp->barrier_seq_snap, gseq);
4494 			WARN_ON_ONCE(READ_ONCE(rdp->barrier_seq_snap) != gseq);
4504 		WARN_ON_ONCE(READ_ONCE(rdp->barrier_seq_snap) != gseq);
4521 	gseq = rcu_state.barrier_sequence;
4525 		WRITE_ONCE(rdp->barrier_seq_snap, gseq);