[dpdk-dev] [PATCH v3 10/10] net/bnxt: fix calculation of max rings

[Ajit Khaparde]

From: Somnath Kotur <somnath.kotur at broadcom.com>

Max Tx rings count could be lesser than max Rx rings in some
cases, so take this into account as well.

Account for stat contexts available(one for each ring) along with
no: of completion rings(one for each ring) to cap the max no: of
Tx /Rx rings that can be possibly created.

Fixes: f03e66cb ("net/bnxt: limit queue count for NS3/Stingray devices")

Signed-off-by: Somnath Kotur <somnath.kotur at broadcom.com>
Reviewed-by: Kalesh Anakkur Purayil <kalesh-anakkur.purayil at broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde at broadcom.com>
---
 drivers/net/bnxt/bnxt.h | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/bnxt/bnxt.h b/drivers/net/bnxt/bnxt.h
index 3487b917e..ddb26814c 100644
--- a/drivers/net/bnxt/bnxt.h
+++ b/drivers/net/bnxt/bnxt.h
@@ -622,12 +622,19 @@ struct bnxt {
 	uint16_t		max_tx_rings;
 	uint16_t		max_rx_rings;
 #define MAX_STINGRAY_RINGS		128U
-#define BNXT_MAX_RINGS(bp) \
+/* For sake of symmetry, max Tx rings == max Rx rings, one stat ctx for each */
+#define BNXT_MAX_RX_RINGS(bp) \
 	(BNXT_STINGRAY(bp) ? RTE_MIN(RTE_MIN(bp->max_rx_rings, \
 					     MAX_STINGRAY_RINGS), \
-				     bp->max_stat_ctx) : \
-				RTE_MIN(bp->max_rx_rings, bp->max_stat_ctx))
+				     bp->max_stat_ctx / 2U) : \
+				RTE_MIN(bp->max_rx_rings, \
+					bp->max_stat_ctx / 2U))
+#define BNXT_MAX_TX_RINGS(bp) \
+	(RTE_MIN((bp)->max_tx_rings, BNXT_MAX_RX_RINGS(bp)))
 
+#define BNXT_MAX_RINGS(bp) \
+	(RTE_MIN((((bp)->max_cp_rings - BNXT_NUM_ASYNC_CPR(bp)) / 2U), \
+		 BNXT_MAX_TX_RINGS(bp)))
 	uint16_t		max_nq_rings;
 	uint16_t		max_l2_ctx;
 	uint16_t		max_rx_em_flows;
-- 
2.21.0 (Apple Git-122.2)