From 4ea2faf5bb13d9ba9f07e996d495c4cbe34a4236 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 29 Nov 2022 16:12:21 +0200 Subject: [PATCH 14/14] net: dpaa2-mac: move rtnl_lock() only around phylink_{,dis}connect_phy() After the introduction of a private mac_lock that serializes access to priv->mac (and port_priv->mac in the switch), the only remaining purpose of rtnl_lock() is to satisfy the locking requirements of phylink_fwnode_phy_connect() and phylink_disconnect_phy(). But the functions these live in, dpaa2_mac_connect() and dpaa2_mac_disconnect(), have contradictory locking requirements. While phylink_fwnode_phy_connect() wants rtnl_lock() to be held, phylink_create() wants it to not be held. Move the rtnl_lock() from top-level (in the dpaa2-eth and dpaa2-switch drivers) to only surround the phylink calls that require it, in the dpaa2-mac library code. This is possible because dpaa2_mac_connect() and dpaa2_mac_disconnect() run unlocked, and there isn't any danger of an AB/BA deadlock between the rtnl_mutex and other private locks. Signed-off-by: Vladimir Oltean Reviewed-by: Ioana Ciornei Tested-by: Ioana Ciornei Signed-off-by: Paolo Abeni --- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 4 ---- drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c | 5 +++++ drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c | 4 ---- 3 files changed, 5 insertions(+), 8 deletions(-) --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -4527,7 +4527,6 @@ static irqreturn_t dpni_irq0_handler_thr dpaa2_eth_set_mac_addr(netdev_priv(net_dev)); dpaa2_eth_update_tx_fqids(priv); - rtnl_lock(); /* We can avoid locking because the "endpoint changed" IRQ * handler is the only one who changes priv->mac at runtime, * so we are not racing with anyone. @@ -4537,7 +4536,6 @@ static irqreturn_t dpni_irq0_handler_thr dpaa2_eth_disconnect_mac(priv); else dpaa2_eth_connect_mac(priv); - rtnl_unlock(); } return IRQ_HANDLED; @@ -4856,9 +4854,7 @@ static int dpaa2_eth_remove(struct fsl_m else fsl_mc_free_irqs(ls_dev); - rtnl_lock(); dpaa2_eth_disconnect_mac(priv); - rtnl_unlock(); dpaa2_eth_free_rings(priv); free_percpu(priv->fd); free_percpu(priv->sgt_cache); --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c @@ -428,7 +428,9 @@ int dpaa2_mac_connect(struct dpaa2_mac * } mac->phylink = phylink; + rtnl_lock(); err = phylink_fwnode_phy_connect(mac->phylink, dpmac_node, 0); + rtnl_unlock(); if (err) { netdev_err(net_dev, "phylink_fwnode_phy_connect() = %d\n", err); goto err_phylink_destroy; @@ -446,7 +448,10 @@ err_pcs_destroy: void dpaa2_mac_disconnect(struct dpaa2_mac *mac) { + rtnl_lock(); phylink_disconnect_phy(mac->phylink); + rtnl_unlock(); + phylink_destroy(mac->phylink); dpaa2_pcs_destroy(mac); of_phy_put(mac->serdes_phy); --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c @@ -1530,7 +1530,6 @@ static irqreturn_t dpaa2_switch_irq0_han } if (status & DPSW_IRQ_EVENT_ENDPOINT_CHANGED) { - rtnl_lock(); /* We can avoid locking because the "endpoint changed" IRQ * handler is the only one who changes priv->mac at runtime, * so we are not racing with anyone. @@ -1540,7 +1539,6 @@ static irqreturn_t dpaa2_switch_irq0_han dpaa2_switch_port_disconnect_mac(port_priv); else dpaa2_switch_port_connect_mac(port_priv); - rtnl_unlock(); } out: @@ -2958,9 +2956,7 @@ static void dpaa2_switch_remove_port(str { struct ethsw_port_priv *port_priv = ethsw->ports[port_idx]; - rtnl_lock(); dpaa2_switch_port_disconnect_mac(port_priv); - rtnl_unlock(); free_netdev(port_priv->netdev); ethsw->ports[port_idx] = NULL; }