[PATCH tip/core/rcu 33/40] srcu: Improve rcu_seq grace-period-counter abstraction

The expedited grace-period code contains several open-coded shifts know the format of an rcu_seq grace-period counter, which is not particularly good style. This commit therefore creates a new rcu_seq_ctr() function that extracts the counter portion of the counter, and an rcu_seq_state() function

[PATCH tip/core/rcu 33/40] srcu: Improve rcu_seq grace-period-counter abstraction

The expedited grace-period code contains several open-coded shifts know the format of an rcu_seq grace-period counter, which is not particularly good style. This commit therefore creates a new rcu_seq_ctr() function that extracts the counter portion of the counter, and an rcu_seq_state() function