Subject: linux-next: manual merge of the rcu tree with the tip tree

From: Stephen Rothwell <[email-masked]>
Date: Fri, 4 Mar 2016 15:13:06 +1100

Hi Paul,

Today's linux-next merge of the rcu tree got a conflict in:

  kernel/rcu/tree.c

between commit:

  27d50c7eeb0f ("rcu: Make CPU_DYING_IDLE an explicit call")

from the tip tree and commit:

  67c583a7de34 ("RCU: Privatize rcu_node::lock")

from the rcu tree.

I fixed it up (see below) and can carry the fix as necessary (no action
is required).

-- 
Cheers,
Stephen Rothwell

diff --cc kernel/rcu/tree.c
index 0bbc1497a0e4,55cea189783f..000000000000
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@@ -4227,43 -4246,6 +4224,43 @@@ static void rcu_prepare_cpu(int cpu
  		rcu_init_percpu_data(cpu, rsp);
  }
  
 +#ifdef CONFIG_HOTPLUG_CPU
 +/*
 + * The CPU is exiting the idle loop into the arch_cpu_idle_dead()
 + * function.  We now remove it from the rcu_node tree's ->qsmaskinit
 + * bit masks.
 + */
 +static void rcu_cleanup_dying_idle_cpu(int cpu, struct rcu_state *rsp)
 +{
 +	unsigned long flags;
 +	unsigned long mask;
 +	struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
 +	struct rcu_node *rnp = rdp->mynode;  /* Outgoing CPU's rdp & rnp. */
 +
 +	if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))
 +		return;
 +
 +	/* Remove outgoing CPU from mask in the leaf rcu_node structure. */
 +	mask = rdp->grpmask;
 +	raw_spin_lock_irqsave_rcu_node(rnp, flags); /* Enforce GP memory-order guarantee. */
 +	rnp->qsmaskinitnext &= ~mask;
- 	raw_spin_unlock_irqrestore(&rnp->lock, flags);
++	raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
 +}
 +
 +void rcu_report_dead(unsigned int cpu)
 +{
 +	struct rcu_state *rsp;
 +
 +	/* QS for any half-done expedited RCU-sched GP. */
 +	preempt_disable();
 +	rcu_report_exp_rdp(&rcu_sched_state,
 +			   this_cpu_ptr(rcu_sched_state.rda), true);
 +	preempt_enable();
 +	for_each_rcu_flavor(rsp)
 +		rcu_cleanup_dying_idle_cpu(cpu, rsp);
 +}
 +#endif
 +
  /*
   * Handle CPU online/offline notification events.
   */