From: Frederic Weisbecker <frede...@kernel.org>

When the boot CPU initializes the per-CPU data on behalf of all possible
CPUs, a sanity check is performed on each of them to make sure none is
initialized in an extended quiescent state.

This check involves a full memory barrier which is useless at this early
boot stage.

Do a plain access instead.

Signed-off-by: Frederic Weisbecker <frede...@kernel.org>
Signed-off-by: Paul E. McKenney <paul...@kernel.org>
---
 kernel/rcu/tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 1a6ef9c5c949e..9fa6d2b557d6c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -4772,7 +4772,7 @@ rcu_boot_init_percpu_data(int cpu)
        rdp->grpmask = leaf_node_cpu_bit(rdp->mynode, cpu);
        INIT_WORK(&rdp->strict_work, strict_work_handler);
        WARN_ON_ONCE(ct->dynticks_nesting != 1);
-       WARN_ON_ONCE(rcu_dynticks_in_eqs(rcu_dynticks_snap(cpu)));
+       WARN_ON_ONCE(rcu_dynticks_in_eqs(ct_dynticks_cpu(cpu)));
        rdp->barrier_seq_snap = rcu_state.barrier_sequence;
        rdp->rcu_ofl_gp_seq = rcu_state.gp_seq;
        rdp->rcu_ofl_gp_state = RCU_GP_CLEANED;
-- 
2.40.1


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