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From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, kernel-team@meta.com,
        rostedt@goodmis.org, Alan Huang <mmpgouride@gmail.com>,
        "Paul E . McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 2/7] docs/RCU: Add the missing rcu_read_unlock()
Date:   Mon, 17 Jul 2023 11:01:05 -0700
Message-Id: <20230717180110.1097362-2-paulmck@kernel.org>
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From: Alan Huang <mmpgouride@gmail.com>

We should exit the RCU read-side critical section before re-entering.

Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 Documentation/RCU/rculist_nulls.rst | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/RCU/rculist_nulls.rst b/Documentation/RCU/rculist_nulls.rst
index 9a734bf54b76..0612a6387d8e 100644
--- a/Documentation/RCU/rculist_nulls.rst
+++ b/Documentation/RCU/rculist_nulls.rst
@@ -29,8 +29,10 @@ algorithms:
   rcu_read_lock()
   obj = lockless_lookup(key);
   if (obj) {
-    if (!try_get_ref(obj)) // might fail for free objects
+    if (!try_get_ref(obj)) { // might fail for free objects
+      rcu_read_unlock();
       goto begin;
+    }
     /*
     * Because a writer could delete object, and a writer could
     * reuse these object before the RCU grace period, we
-- 
2.40.1