rcu: Make rcutree_dying_cpu() use its "cpu" parameter

paulmckrcu · paulmckrcu · commit 4aa846f97c0c · 2021-09-13T16:32:46.000-07:00
The CPU-hotplug functions take a "cpu" parameter, but rcutree_dying_cpu()
ignores it in favor of this_cpu_ptr().  This works at the moment, but
it would be better to be consistent.  This might also work better given
some possible future changes.  This commit therefore uses per_cpu_ptr()
to avoid ignoring the rcutree_dying_cpu() function's argument.

Signed-off-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
@@ -2356,7 +2356,7 @@ rcu_check_quiescent_state(struct rcu_data *rdp)
 int rcutree_dying_cpu(unsigned int cpu)
 {
 	bool blkd;
-	struct rcu_data *rdp = this_cpu_ptr(&rcu_data);
+	struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);
 	struct rcu_node *rnp = rdp->mynode;
 
 	if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))

Original file line number	Diff line number	Diff line change
`@@ -2356,7 +2356,7 @@ rcu_check_quiescent_state(struct rcu_data *rdp)`
`2356`	`2356`	`int rcutree_dying_cpu(unsigned int cpu)`
`2357`	`2357`	`{`
`2358`	`2358`	`bool blkd;`
`2359`		`- struct rcu_data *rdp = this_cpu_ptr(&rcu_data);`
	`2359`	`+ struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);`
`2360`	`2360`	`struct rcu_node *rnp = rdp->mynode;`
`2361`	`2361`
`2362`	`2362`	`if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))`