[PATCH 19.11 1/2] net/ena: check memory BAR before initializing LLQ

[Dawid Gorecki]

[ upstream commit 9ae7a13f8247319f63402107c8304ba57c3f4308 ]

The ena_com_config_dev_mode() performs many calculations related to LLQ
and then performs an admin queue call to configure LLQ in the device.

All of the operations performed by ena_com_config_dev_mode() are
unnecessary if membar hasn't been found. Move the dev_mem_base check
before ena_com_config_dev_mode() call. This prevents the unnecessary
operations from being performed.

Fixes: 2fca2a98c0d1 ("net/ena: support LLQv2")
Cc: stable at dpdk.org

Signed-off-by: Dawid Gorecki <dgr at semihalf.com>
Reviewed-by: Michal Krawczyk <mk at semihalf.com>
Reviewed-by: Shai Brandes <shaibran at amazon.com>
---
 drivers/net/ena/ena_ethdev.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index 7601d2fa25..dc30370a8f 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -1637,6 +1637,13 @@ ena_set_queues_placement_policy(struct ena_adapter *adapter,
 		return 0;
 	}
 
+	if (adapter->dev_mem_base == NULL) {
+		PMD_DRV_LOG(ERR,
+			"LLQ is advertised as supported, but device doesn't expose mem bar\n");
+		ena_dev->tx_mem_queue_type = ENA_ADMIN_PLACEMENT_POLICY_HOST;
+		return 0;
+	}
+
 	rc = ena_com_config_dev_mode(ena_dev, llq, llq_default_configurations);
 	if (unlikely(rc)) {
 		PMD_INIT_LOG(WARNING, "Failed to config dev mode. "
@@ -1649,13 +1656,6 @@ ena_set_queues_placement_policy(struct ena_adapter *adapter,
 	if (ena_dev->tx_mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST)
 		return 0;
 
-	if (!adapter->dev_mem_base) {
-		PMD_DRV_LOG(ERR, "Unable to access LLQ bar resource. "
-			"Fallback to host mode policy.\n.");
-		ena_dev->tx_mem_queue_type = ENA_ADMIN_PLACEMENT_POLICY_HOST;
-		return 0;
-	}
-
 	ena_dev->mem_bar = adapter->dev_mem_base;
 
 	return 0;
-- 
2.35.1