[PATCH tip/core/rcu 24/40] srcu: Move to state-based grace-period sequencing

The current SRCU grace-period processing might never reach the last portion of srcu_advance_batches(). This is OK given the current implementation, as the first portion, up to the try_check_zero() following the srcu_flip() is sufficient to drive grace periods forward. However, it has the

[PATCH tip/core/rcu 24/40] srcu: Move to state-based grace-period sequencing

The current SRCU grace-period processing might never reach the last portion of srcu_advance_batches(). This is OK given the current implementation, as the first portion, up to the try_check_zero() following the srcu_flip() is sufficient to drive grace periods forward. However, it has the