Commit 780cd590 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcu: Remove rsp parameter from CPU hotplug functions 



There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
rcu_cleanup_dying_cpu() and rcu_cleanup_dead_cpu().  And, as long as
we are in the neighborhood, inlines them into rcutree_dying_cpu() and
rcutree_dead_cpu(), respectively.  This also eliminates a pair of
for_each_rcu_flavor() loops.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
parent 8087d3e3

kernel/rcu/tree.c

+11 −32
Original line number Diff line number Diff line
@@ -2402,20 +2402,22 @@ rcu_check_quiescent_state(struct rcu_data *rdp) 
}



/*

 * Trace the fact that this CPU is going offline.

 * Near the end of the offline process.  Trace the fact that this CPU

 * is going offline.

 */

static void rcu_cleanup_dying_cpu(struct rcu_state *rsp)

int rcutree_dying_cpu(unsigned int cpu)

{

	RCU_TRACE(bool blkd;)

	RCU_TRACE(struct rcu_data *rdp = this_cpu_ptr(&rcu_data);)

	RCU_TRACE(struct rcu_node *rnp = rdp->mynode;)



	if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))

		return;

		return 0;



	RCU_TRACE(blkd = !!(rnp->qsmask & rdp->grpmask);)

	trace_rcu_grace_period(rsp->name, rnp->gp_seq,

	trace_rcu_grace_period(rcu_state.name, rnp->gp_seq,

			       blkd ? TPS("cpuofl") : TPS("cpuofl-bgp"));

	return 0;

}



/*
@@ -2469,16 +2471,19 @@ static void rcu_cleanup_dead_rnp(struct rcu_node *rnp_leaf) 
 * There can only be one CPU hotplug operation at a time, so no need for

 * explicit locking.

 */

static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp)

int rcutree_dead_cpu(unsigned int cpu)

{

	struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);

	struct rcu_node *rnp = rdp->mynode;  /* Outgoing CPU's rdp & rnp. */



	if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))

		return;

		return 0;



	/* Adjust any no-longer-needed kthreads. */

	rcu_boost_kthread_setaffinity(rnp, -1);

	/* Do any needed no-CB deferred wakeups from this CPU. */

	do_nocb_deferred_wakeup(per_cpu_ptr(&rcu_data, cpu));

	return 0;

}



/*
@@ -3514,32 +3519,6 @@ int rcutree_offline_cpu(unsigned int cpu) 
	return 0;

}



/*

 * Near the end of the offline process.  We do only tracing here.

 */

int rcutree_dying_cpu(unsigned int cpu)

{

	struct rcu_state *rsp;



	for_each_rcu_flavor(rsp)

		rcu_cleanup_dying_cpu(rsp);

	return 0;

}



/*

 * The outgoing CPU is gone and we are running elsewhere.

 */

int rcutree_dead_cpu(unsigned int cpu)

{

	struct rcu_state *rsp;



	for_each_rcu_flavor(rsp) {

		rcu_cleanup_dead_cpu(cpu, rsp);

		do_nocb_deferred_wakeup(per_cpu_ptr(&rcu_data, cpu));

	}

	return 0;

}



static DEFINE_PER_CPU(int, rcu_cpu_started);



/*