[PATCH 01/10] lib: Use rcu_preempt_depth() to replace current->rcu_read_lock_nesting

[Lai Jiangshan <jiangshanlai@gmail.com>]

From: Lai Jiangshan <jiangshan.ljs@antgroup.com>

Use the general wrapper rcu_preempt_depth() instead of the open code.

Prepare for enabling per-cpu rcu_preempt_count, in which case
current->rcu_read_lock_nesting might not be synced with the real depth.

Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
---
 lib/locking-selftest.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 6f6a5fc85b42..9bb41fb18088 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -1434,7 +1434,7 @@ static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
 #ifdef CONFIG_SMP
 	int saved_mgd_count = current->migration_disabled;
 #endif
-	int saved_rcu_count = current->rcu_read_lock_nesting;
+	int saved_rcu_count = rcu_preempt_depth();
 #endif
 
 	WARN_ON(irqs_disabled());
@@ -1476,9 +1476,9 @@ static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
 		migrate_enable();
 #endif
 
-	while (current->rcu_read_lock_nesting > saved_rcu_count)
+	while (rcu_preempt_depth() > saved_rcu_count)
 		rcu_read_unlock();
-	WARN_ON_ONCE(current->rcu_read_lock_nesting < saved_rcu_count);
+	WARN_ON_ONCE(rcu_preempt_depth() < saved_rcu_count);
 #endif
 
 #ifdef CONFIG_TRACE_IRQFLAGS
-- 
2.19.1.6.gb485710b