[PATCH] net/bonding: fix descriptor limit reporting

[Ivan Malov]

Commit 5be3b40fea60 ("net/bonding: fix values of descriptor limits")
breaks reporting of "nb_min" and "nb_align" values obtained from
back-end devices' descriptor limits. This means that work done
by eth_bond_slave_inherit_desc_lim_first() as well as
eth_bond_slave_inherit_desc_lim_next() gets dismissed.

Revert the offending commit and use proper workaround
for the test case mentioned in the said commit.

Meanwhile, the test case itself might be poorly constructed.
It tries to run a bond with no back-end devices attached,
but, according to [1] ("Requirements / Limitations"),
at least one back-end device must be attached.

[1] doc/guides/prog_guide/link_bonding_poll_mode_drv_lib.rst

Fixes: 5be3b40fea60 ("net/bonding: fix values of descriptor limits")
Cc: stable at dpdk.org

Signed-off-by: Ivan Malov <ivan.malov at oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
---
 drivers/net/bonding/rte_eth_bond_pmd.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/net/bonding/rte_eth_bond_pmd.c b/drivers/net/bonding/rte_eth_bond_pmd.c
index 3191158ca7..a5429f5e97 100644
--- a/drivers/net/bonding/rte_eth_bond_pmd.c
+++ b/drivers/net/bonding/rte_eth_bond_pmd.c
@@ -2200,8 +2200,6 @@ bond_ethdev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 
 	uint16_t max_nb_rx_queues = UINT16_MAX;
 	uint16_t max_nb_tx_queues = UINT16_MAX;
-	uint16_t max_rx_desc_lim = UINT16_MAX;
-	uint16_t max_tx_desc_lim = UINT16_MAX;
 
 	dev_info->max_mac_addrs = BOND_MAX_MAC_ADDRS;
 
@@ -2235,12 +2233,6 @@ bond_ethdev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 
 			if (slave_info.max_tx_queues < max_nb_tx_queues)
 				max_nb_tx_queues = slave_info.max_tx_queues;
-
-			if (slave_info.rx_desc_lim.nb_max < max_rx_desc_lim)
-				max_rx_desc_lim = slave_info.rx_desc_lim.nb_max;
-
-			if (slave_info.tx_desc_lim.nb_max < max_tx_desc_lim)
-				max_tx_desc_lim = slave_info.tx_desc_lim.nb_max;
 		}
 	}
 
@@ -2252,8 +2244,10 @@ bond_ethdev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 	memcpy(&dev_info->default_txconf, &internals->default_txconf,
 	       sizeof(dev_info->default_txconf));
 
-	dev_info->rx_desc_lim.nb_max = max_rx_desc_lim;
-	dev_info->tx_desc_lim.nb_max = max_tx_desc_lim;
+	memcpy(&dev_info->rx_desc_lim, &internals->rx_desc_lim,
+	       sizeof(dev_info->rx_desc_lim));
+	memcpy(&dev_info->tx_desc_lim, &internals->tx_desc_lim,
+	       sizeof(dev_info->tx_desc_lim));
 
 	/**
 	 * If dedicated hw queues enabled for link bonding device in LACP mode
@@ -3387,6 +3381,13 @@ bond_alloc(struct rte_vdev_device *dev, uint8_t mode)
 	memset(&internals->rx_desc_lim, 0, sizeof(internals->rx_desc_lim));
 	memset(&internals->tx_desc_lim, 0, sizeof(internals->tx_desc_lim));
 
+	/*
+	 * Do not restrict descriptor counts until
+	 * the first back-end device gets attached.
+	 */
+	internals->rx_desc_lim.nb_max = UINT16_MAX;
+	internals->tx_desc_lim.nb_max = UINT16_MAX;
+
 	memset(internals->active_slaves, 0, sizeof(internals->active_slaves));
 	memset(internals->slaves, 0, sizeof(internals->slaves));
 
-- 
2.30.2