From: Paul E. McKenney <paulmck@linux.ibm.com>
Date: Mon, 5 Nov 2018 22:20:57 +0000 (-0800)
Subject: rcu: Replace this_cpu_ptr() with __this_cpu_read()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=117f683c6e0104e1d6dfe8f143ea9c24ab069044;p=linux.git

rcu: Replace this_cpu_ptr() with __this_cpu_read()

Because __this_cpu_read() can be lighter weight than equivalent uses of
this_cpu_ptr(), this commit replaces the latter with the former.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
---

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 618956cc7a55f..0bb1c1593ca41 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -597,7 +597,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
  */
 static bool rcu_preempt_need_deferred_qs(struct task_struct *t)
 {
-	return (this_cpu_ptr(&rcu_data)->deferred_qs ||
+	return (__this_cpu_read(rcu_data.deferred_qs) ||
 		READ_ONCE(t->rcu_read_unlock_special.s)) &&
 	       t->rcu_read_lock_nesting <= 0;
 }