bnxt_en: Don't use rtnl lock to protect link change logic in workqueue.

[ Upstream commit e2dc9b6e38fa3919e63d6d7905da70ca41cbf908 ]

As a further improvement to the PF/VF link change logic, use a private
mutex instead of the rtnl lock to protect link change logic.  With the
new mutex, we don't have to take the rtnl lock in the workqueue when
we have to handle link related functions.  If the VF and PF drivers
are running on the same host and both take the rtnl lock and one is
waiting for the other, it will cause timeout.  This patch fixes these
timeouts.

Fixes: 90c694bb7181 ("bnxt_en: Fix RTNL lock usage on bnxt_update_link().")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 208e9dacfd343d6b8a4b5b381511b04c7c1160e4..a036f7039d76722468bd24c85a27bc9ffea4519f 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -5580,7 +5580,9 @@ static int __bnxt_open_nic(struct bnxt *bp, bool irq_re_init, bool link_re_init)
        }
 
        if (link_re_init) {
+               mutex_lock(&bp->link_lock);
                rc = bnxt_update_phy_setting(bp);
+               mutex_unlock(&bp->link_lock);
                if (rc)
                        netdev_warn(bp->dev, "failed to update phy settings\n");
        }
@@ -6230,30 +6232,28 @@ static void bnxt_sp_task(struct work_struct *work)
        if (test_and_clear_bit(BNXT_PERIODIC_STATS_SP_EVENT, &bp->sp_event))
                bnxt_hwrm_port_qstats(bp);
 
-       /* These functions below will clear BNXT_STATE_IN_SP_TASK.  They
-        * must be the last functions to be called before exiting.
-        */
        if (test_and_clear_bit(BNXT_LINK_CHNG_SP_EVENT, &bp->sp_event)) {
-               int rc = 0;
+               int rc;
 
+               mutex_lock(&bp->link_lock);
                if (test_and_clear_bit(BNXT_LINK_SPEED_CHNG_SP_EVENT,
                                       &bp->sp_event))
                        bnxt_hwrm_phy_qcaps(bp);
 
-               bnxt_rtnl_lock_sp(bp);
-               if (test_bit(BNXT_STATE_OPEN, &bp->state))
-                       rc = bnxt_update_link(bp, true);
-               bnxt_rtnl_unlock_sp(bp);
+               rc = bnxt_update_link(bp, true);
+               mutex_unlock(&bp->link_lock);
                if (rc)
                        netdev_err(bp->dev, "SP task can't update link (rc: %x)\n",
                                   rc);
        }
        if (test_and_clear_bit(BNXT_HWRM_PORT_MODULE_SP_EVENT, &bp->sp_event)) {
-               bnxt_rtnl_lock_sp(bp);
-               if (test_bit(BNXT_STATE_OPEN, &bp->state))
-                       bnxt_get_port_module_status(bp);
-               bnxt_rtnl_unlock_sp(bp);
+               mutex_lock(&bp->link_lock);
+               bnxt_get_port_module_status(bp);
+               mutex_unlock(&bp->link_lock);
        }
+       /* These functions below will clear BNXT_STATE_IN_SP_TASK.  They
+        * must be the last functions to be called before exiting.
+        */
        if (test_and_clear_bit(BNXT_RESET_TASK_SP_EVENT, &bp->sp_event))
                bnxt_reset(bp, false);
 
@@ -6788,6 +6788,7 @@ static int bnxt_probe_phy(struct bnxt *bp)
                           rc);
                return rc;
        }
+       mutex_init(&bp->link_lock);
 
        rc = bnxt_update_link(bp, false);
        if (rc) {

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 666bc0608ed7d2f3539e503fabb8dbc825796afd..017c10c537159370f79296f91bbbebbd453d8e68 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1109,6 +1109,10 @@ struct bnxt {
        unsigned long           *ntp_fltr_bmap;
        int                     ntp_fltr_count;
 
+       /* To protect link related settings during link changes and
+        * ethtool settings changes.
+        */
+       struct mutex            link_lock;
        struct bnxt_link_info   link_info;
        struct ethtool_eee      eee;
        u32                     lpi_tmr_lo;

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index cde4b96f3153f7cbfee033fb8d41c9040ec592f0..3a352f76e633cbfabeeb4c6dd8fb0cbb3b04d649 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -793,6 +793,7 @@ static int bnxt_get_link_ksettings(struct net_device *dev,
        u32 ethtool_speed;
 
        ethtool_link_ksettings_zero_link_mode(lk_ksettings, supported);
+       mutex_lock(&bp->link_lock);
        bnxt_fw_to_ethtool_support_spds(link_info, lk_ksettings);
 
        ethtool_link_ksettings_zero_link_mode(lk_ksettings, advertising);
@@ -840,6 +841,7 @@ static int bnxt_get_link_ksettings(struct net_device *dev,
                        base->port = PORT_FIBRE;
        }
        base->phy_address = link_info->phy_addr;
+       mutex_unlock(&bp->link_lock);
 
        return 0;
 }
@@ -926,6 +928,7 @@ static int bnxt_set_link_ksettings(struct net_device *dev,
        if (!BNXT_SINGLE_PF(bp))
                return -EOPNOTSUPP;
 
+       mutex_lock(&bp->link_lock);
        if (base->autoneg == AUTONEG_ENABLE) {
                BNXT_ETHTOOL_TO_FW_SPDS(fw_advertising, lk_ksettings,
                                        advertising);
@@ -970,6 +973,7 @@ static int bnxt_set_link_ksettings(struct net_device *dev,
                rc = bnxt_hwrm_set_link_setting(bp, set_pause, false);
 
 set_setting_exit:
+       mutex_unlock(&bp->link_lock);
        return rc;
 }