Commit c0f97f20 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcu: Move rcu_cpu_started per-CPU variable to rcu_data 



When the rcu_cpu_started per-CPU variable was added by commit
f64c6013 ("rcu/x86: Provide early rcu_cpu_starting() callback"),
there were multiple sets of per-CPU rcu_data structures.  Therefore, the
rcu_cpu_started flag was added as a separate per-CPU variable.  But now
there is only one set of per-CPU rcu_data structures, so this commit
moves rcu_cpu_started to a new ->cpu_started field in that structure.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent df9a30fd

kernel/rcu/tree.c

+4 −7
Original line number Diff line number Diff line
@@ -3967,8 +3967,6 @@ int rcutree_offline_cpu(unsigned int cpu) 
	return 0;

}



static DEFINE_PER_CPU(int, rcu_cpu_started);



/*

 * Mark the specified CPU as being online so that subsequent grace periods

 * (both expedited and normal) will wait on it.  Note that this means that
@@ -3988,12 +3986,11 @@ void rcu_cpu_starting(unsigned int cpu) 
	struct rcu_node *rnp;

	bool newcpu;



	if (per_cpu(rcu_cpu_started, cpu))

	rdp = per_cpu_ptr(&rcu_data, cpu);

	if (rdp->cpu_started)

		return;

	rdp->cpu_started = true;



	per_cpu(rcu_cpu_started, cpu) = 1;



	rdp = per_cpu_ptr(&rcu_data, cpu);

	rnp = rdp->mynode;

	mask = rdp->grpmask;

	raw_spin_lock_irqsave_rcu_node(rnp, flags);
@@ -4053,7 +4050,7 @@ void rcu_report_dead(unsigned int cpu) 
	raw_spin_unlock_irqrestore_rcu_node(rnp, flags);

	raw_spin_unlock(&rcu_state.ofl_lock);



	per_cpu(rcu_cpu_started, cpu) = 0;

	rdp->cpu_started = false;

}



/*

kernel/rcu/tree.h

+1 −0
Original line number Diff line number Diff line
@@ -156,6 +156,7 @@ struct rcu_data { 
	bool		beenonline;	/* CPU online at least once. */

	bool		gpwrap;		/* Possible ->gp_seq wrap. */

	bool		exp_deferred_qs; /* This CPU awaiting a deferred QS? */

	bool		cpu_started;	/* RCU watching this onlining CPU. */

	struct rcu_node *mynode;	/* This CPU's leaf of hierarchy */

	unsigned long grpmask;		/* Mask to apply to leaf qsmask. */

	unsigned long	ticks_this_gp;	/* The number of scheduling-clock */

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