123 struct rcu_node {  struct
124 	raw_spinlock_t lock;	/* Root rcu_node's lock protects some */  argument
128 				/*  behind the root rcu_node's gpnum. */  argument
131 				/*  behind the root rcu_node's gpnum. */  argument
134 				/*  In leaf rcu_node, each bit corresponds to */  argument
157 				/*  rcu_node tree? */  argument
158 	struct rcu_node *parent;  argument
177 				/*  boosting is needed for this rcu_node */  argument
189 				/*  boosting for this rcu_node structure. */  argument
190 	unsigned int boost_kthread_status;
192 	unsigned long n_tasks_boosted;
194 	unsigned long n_exp_boosts;
196 	unsigned long n_normal_boosts;
198 	unsigned long n_balk_blkd_tasks;
222  * Do a full breadth-first scan of the rcu_node structures for the  argument