target/linux/generic/backport-5.15/765-v5.17-02-net-next-net-dsa-merge-rtnl_lock-sections-in-dsa_slave_create.patch

   1 From e31dbd3b6aba585231cd84a87adeb22e7c6a8c19 Mon Sep 17 00:00:00 2001
   2 From: Vladimir Oltean <vladimir.oltean@nxp.com>
   3 Date: Thu, 6 Jan 2022 01:11:13 +0200
   4 Subject: [PATCH 2/6] net: dsa: merge rtnl_lock sections in dsa_slave_create
   5
   6 Currently dsa_slave_create() has two sequences of rtnl_lock/rtnl_unlock
   7 in a row. Remove the rtnl_unlock() and rtnl_lock() in between, such that
   8 the operation can execute slighly faster.
   9
  10 Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
  11 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
  12 Signed-off-by: David S. Miller <davem@davemloft.net>
  13 ---
  14  net/dsa/slave.c | 4 +---
  15  1 file changed, 1 insertion(+), 3 deletions(-)
  16
  17 --- a/net/dsa/slave.c
  18 +++ b/net/dsa/slave.c
  19 @@ -1988,14 +1988,12 @@ int dsa_slave_create(struct dsa_port *po
  20         }
  21
  22         rtnl_lock();
  23 +
  24         ret = dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN);
  25 -       rtnl_unlock();
  26         if (ret && ret != -EOPNOTSUPP)
  27                 dev_warn(ds->dev, "nonfatal error %d setting MTU to %d on port %d\n",
  28                          ret, ETH_DATA_LEN, port->index);
  29
  30 -       rtnl_lock();
  31 -
  32         ret = register_netdevice(slave_dev);
  33         if (ret) {
  34                 netdev_err(master, "error %d registering interface %s\n",