From a9f2fbc42f0c58df614896a407fd694899315233 Mon Sep 17 00:00:00 2001 From: Shahaf Shuler Date: Tue, 31 Jan 2017 15:13:38 +0200 Subject: [PATCH] net/mlx5: fix inconsistent link status Querying the link status can end up being in an inconsistent state, like the port is reporting speed although it is down. For this case another query is scheduled. A race condition can occur between the scheduled query and link status interrupt handlers. When the scheduled query by-pass interrupt handlers, the link status will be stuck in an inconsistent state. This patch addresses the race condition by not blocking link status queries in case delayed query is used. Fixes: 198a3c339a8f ("mlx5: handle link status interrupts") Cc: stable@dpdk.org Signed-off-by: Shahaf Shuler Acked-by: Nelio Laranjeiro --- drivers/net/mlx5/mlx5_ethdev.c | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c index a46526ef6d..de9d1029f5 100644 --- a/drivers/net/mlx5/mlx5_ethdev.c +++ b/drivers/net/mlx5/mlx5_ethdev.c @@ -1125,7 +1125,7 @@ static int priv_dev_link_status_handler(struct priv *priv, struct rte_eth_dev *dev) { struct ibv_async_event event; - int port_change = 0; + struct rte_eth_link *link = &dev->data->dev_link; int ret = 0; /* Read all message and acknowledge them. */ @@ -1133,29 +1133,24 @@ priv_dev_link_status_handler(struct priv *priv, struct rte_eth_dev *dev) if (ibv_get_async_event(priv->ctx, &event)) break; - if (event.event_type == IBV_EVENT_PORT_ACTIVE || - event.event_type == IBV_EVENT_PORT_ERR) - port_change = 1; - else + if (event.event_type != IBV_EVENT_PORT_ACTIVE && + event.event_type != IBV_EVENT_PORT_ERR) DEBUG("event type %d on port %d not handled", event.event_type, event.element.port_num); ibv_ack_async_event(&event); } - - if (port_change ^ priv->pending_alarm) { - struct rte_eth_link *link = &dev->data->dev_link; - - priv->pending_alarm = 0; - mlx5_link_update(dev, 0); - if (((link->link_speed == 0) && link->link_status) || - ((link->link_speed != 0) && !link->link_status)) { + mlx5_link_update(dev, 0); + if (((link->link_speed == 0) && link->link_status) || + ((link->link_speed != 0) && !link->link_status)) { + if (!priv->pending_alarm) { /* Inconsistent status, check again later. */ priv->pending_alarm = 1; rte_eal_alarm_set(MLX5_ALARM_TIMEOUT_US, mlx5_dev_link_status_handler, dev); - } else - ret = 1; + } + } else { + ret = 1; } return ret; } @@ -1175,6 +1170,7 @@ mlx5_dev_link_status_handler(void *arg) priv_lock(priv); assert(priv->pending_alarm == 1); + priv->pending_alarm = 0; ret = priv_dev_link_status_handler(priv, dev); priv_unlock(priv); if (ret) -- 2.20.1