Merge remote-tracking branches 'asoc/topic/wm8776', 'asoc/topic/wm8804', 'asoc/topic...

[cascardo/linux.git] / kernel / rcu / tree_plugin.h

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 387dd45..c1d7f27 100644 (file)
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2049,6 +2049,33 @@ static void wake_nocb_leader(struct rcu_data *rdp, bool force)
        }
 }
 
+/*
+ * Does the specified CPU need an RCU callback for the specified flavor
+ * of rcu_barrier()?
+ */
+static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu)
+{
+       struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
+       struct rcu_head *rhp;
+
+       /* No-CBs CPUs might have callbacks on any of three lists. */
+       rhp = ACCESS_ONCE(rdp->nocb_head);
+       if (!rhp)
+               rhp = ACCESS_ONCE(rdp->nocb_gp_head);
+       if (!rhp)
+               rhp = ACCESS_ONCE(rdp->nocb_follower_head);
+
+       /* Having no rcuo kthread but CBs after scheduler starts is bad! */
+       if (!ACCESS_ONCE(rdp->nocb_kthread) && rhp) {
+               /* RCU callback enqueued before CPU first came online??? */
+               pr_err("RCU: Never-onlined no-CBs CPU %d has CB %p\n",
+                      cpu, rhp->func);
+               WARN_ON_ONCE(1);
+       }
+
+       return !!rhp;
+}
+
 /*
  * Enqueue the specified string of rcu_head structures onto the specified
  * CPU's no-CBs lists.  The CPU is specified by rdp, the head of the
@@ -2642,6 +2669,12 @@ static bool init_nocb_callback_list(struct rcu_data *rdp)
 
 #else /* #ifdef CONFIG_RCU_NOCB_CPU */
 
+static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu)
+{
+       WARN_ON_ONCE(1); /* Should be dead code. */
+       return false;
+}
+
 static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp)
 {
 }