Commit f37599e6 authored by Joel Fernandes (Google)'s avatar Joel Fernandes (Google) Committed by Paul E. McKenney
Browse files

rcu: Clarify comments about FQS loop reporting quiescent states 



Since at least v4.19, the FQS loop no longer reports quiescent states
for offline CPUs except in emergency situations.

This commit therefore fixes the comment in rcu_gp_init() to match the
current code.

Signed-off-by: default avatarJoel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 4569c5ee

kernel/rcu/tree.c

+7 −4
Original line number Diff line number Diff line
@@ -1706,10 +1706,13 @@ static bool rcu_gp_init(void) 
	raw_spin_unlock_irq_rcu_node(rnp);



	/*

	 * Apply per-leaf buffered online and offline operations to the

	 * rcu_node tree.  Note that this new grace period need not wait

	 * for subsequent online CPUs, and that quiescent-state forcing

	 * will handle subsequent offline CPUs.

	 * Apply per-leaf buffered online and offline operations to

	 * the rcu_node tree. Note that this new grace period need not

	 * wait for subsequent online CPUs, and that RCU hooks in the CPU

	 * offlining path, when combined with checks in this function,

	 * will handle CPUs that are currently going offline or that will

	 * go offline later.  Please also refer to "Hotplug CPU" section

	 * of RCU's Requirements documentation.

	 */

	rcu_state.gp_state = RCU_GP_ONOFF;

	rcu_for_each_leaf_node(rnp) {

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