251  * rcu_softirq_qs - Provide a set of RCU quiescent states in softirq processing
253  * Mark a quiescent state for RCU, Tasks RCU, and Tasks Trace RCU.
287  * newly onlined CPU is no longer in an extended quiescent state.
289  * to the next non-quiescent value.
304  * indicates that RCU is in an extended quiescent state.
319  * extended quiescent state since @snap. Note that this doesn't check if it
342  * CPU remains within a single extended quiescent state.
348 	// If not quiescent, force back to earlier extended quiescent state.  in rcu_watching_zero_in_eqs()
355 	// If still in the same extended quiescent state, we are good!  in rcu_watching_zero_in_eqs()
361  * which is a quiescent state.  This is called when the need for a
362  * quiescent state is urgent, so we burn an atomic operation and full
451  * quiescent-state help from rcu_note_context_switch().
460  * idle CPUs before taking active measures to force quiescent states.
616 			 "RCU in extended quiescent state!");  in rcu_irq_exit_check_preempt()
626  * execution is an RCU quiescent state and the time executing in the kernel
632  * Therefore, if a nohz_full CPU fails to report a quiescent state
636  * tick, which will enable RCU to detect that CPU's quiescent states,
638  * The tick will be disabled once a quiescent state is reported for
656 			 "Illegal rcu_irq_enter_check_tick() from extended quiescent state");  in __rcu_irq_enter_check_tick()
666 	// We get here only when not in an extended quiescent state and  in __rcu_irq_enter_check_tick()
675 		// quiescent state.  Turn on the tick!  in __rcu_irq_enter_check_tick()
704  * to get to a quiescent state, disable it.
744  * If a holdout task is actually running, request an urgent quiescent
762  * When trying to report a quiescent state on behalf of some other CPU,
780  * credit them with an implicit quiescent state.  Return 1 if this CPU
781  * is in dynticks idle mode, which is an extended quiescent state.
806  * Returns positive if the specified CPU has passed through a quiescent state
824 	 * already acknowledged the request to pass through a quiescent  in rcu_watching_snap_recheck()
837 	 * perspective has not yet reported a quiescent state.  After all,  in rcu_watching_snap_recheck()
838 	 * the offline CPU should have reported a quiescent state during  in rcu_watching_snap_recheck()
876 	 * CPU failed to pass through a quiescent state.  This code  in rcu_watching_snap_recheck()
1248  * quiescent state.  This is intended to be invoked when the CPU notices
1295 		 * set up to detect a quiescent state, otherwise don't  in __note_gp_changes()
1908 	 * Set the quiescent-state-needed bits in all the rcu_node  in rcu_gp_init()
1933 		/* Quiescent states for tasks on any now-offline CPUs. */  in rcu_gp_init()
1952  * Helper function for swait_event_idle_exclusive() wakeup at force-quiescent-state
1963 	// Someone like call_rcu() requested a force-quiescent-state scan.  in rcu_gp_fqs_check_wake()
1976  * Do one round of quiescent-state forcing.
2012  * Loop doing repeated quiescent-state forcing until the grace period ends.
2057 		 * the corresponding leaf nodes have passed through their quiescent state.  in rcu_gp_fqs_loop()
2062 		/* If time for quiescent-state forcing, do it. */  in rcu_gp_fqs_loop()
2246 		/* Handle quiescent-state forcing. */  in rcu_gp_kthread()
2257  * Report a full set of quiescent states to the rcu_state data structure.
2260  * kthread or it awakens itself for the next round of quiescent-state
2277  * Allows quiescent states for a group of CPUs to be reported at one go
2281  * is the grace-period snapshot, which means that the quiescent states
2286  * disabled.  This allows propagating quiescent state due to resumed tasks
2339 	 * Get here if we are the last CPU to pass through a quiescent  in rcu_report_qs_rnp()
2347  * Record a quiescent state for all tasks that were previously queued
2366 		return;  /* Still need more quiescent states! */  in rcu_report_unblock_qs_rnp()
2389  * Record a quiescent state for the specified CPU to that CPU's rcu_data
2406 		 * The grace period in which this quiescent state was  in rcu_report_qs_rdp()
2408 		 * We will instead need a new quiescent state that lies  in rcu_report_qs_rdp()
2445  * quiescent state for this grace period, and record that fact if so.
2461 	 * Was there a quiescent state since the beginning of the grace  in rcu_check_quiescent_state()
2591 			// But rcuc kthreads can delay quiescent-state  in rcu_do_batch()
2640  * and checks to see if this CPU is in a non-context-switch quiescent
2644  * purpose of providing the needed quiescent state.
2660 		/* Idle and userspace execution already are quiescent states. */  in rcu_sched_clock_irq()
2679  * CPUs have reported a quiescent state and on which there are tasks
2682  * each CPU that has not yet reported a quiescent state.
2740  * Force quiescent states on reluctant CPUs, and also detect which
2798 	/* Report any deferred quiescent states if preemption enabled. */  in rcu_core()
2806 	/* Update RCU state based on any recent quiescent states. */  in rcu_core()
2973 	 * If called from an extended quiescent state, invoke the RCU  in call_rcu_core()
4433 	/* Is the RCU core waiting for a quiescent state from this CPU? */  in rcu_pending()
5202 		/* Report quiescent state -before- changing ->qsmaskinitnext! */  in rcutree_report_cpu_dead()