[PATCH rcu 14/14] rxrpc: Use call_rcu_flush() instead of call_rcu()

From: Paul E. McKenney
Date: Wed Oct 19 2022 - 18:52:35 EST


From: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx>

call_rcu() changes to save power may cause slowness. Use the
call_rcu_flush() API instead which reverts to the old behavior.

We find this via inspection that the RCU callback does a wakeup of a
thread. This usually indicates that something is waiting on it. To be
safe, let us use call_rcu_flush() here instead.

Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
net/rxrpc/conn_object.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 22089e37e97f0..fdcfb509cc443 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -253,7 +253,7 @@ void rxrpc_kill_connection(struct rxrpc_connection *conn)
* must carry a ref on the connection to prevent us getting here whilst
* it is queued or running.
*/
- call_rcu(&conn->rcu, rxrpc_destroy_connection);
+ call_rcu_flush(&conn->rcu, rxrpc_destroy_connection);
}

/*
--
2.31.1.189.g2e36527f23