diff mbox series

net/bnxt: fix doorbell write ordering

Message ID 20201214185144.252284-1-lance.richardson@broadcom.com (mailing list archive)
State Superseded, archived
Delegated to: Ajit Khaparde
Headers
Series net/bnxt: fix doorbell write ordering |

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/Intel-compilation success Compilation OK
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-testing success Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-intel-Performance success Performance Testing PASS

Commit Message

Lance Richardson Dec. 14, 2020, 6:51 p.m. UTC 
  Write completion queue doorbell before receive descriptor
doorbell to avoid possiblity of completion queue overflow
when completion queue size is equal to receive descriptor
ring size. Remove unnecessary compiler barriers (db write
functions have the necessary barriers.)

Fixes: 637e34befd9c ("net/bnxt: optimize Rx processing")
Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
Reviewed-by: Ajit Kumar Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Cc: stable@dpdk.org
---
 drivers/net/bnxt/bnxt_rxr.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/bnxt/bnxt_rxr.c b/drivers/net/bnxt/bnxt_rxr.c
index e2d388e69f..ffdeeecc3a 100644
--- a/drivers/net/bnxt/bnxt_rxr.c
+++ b/drivers/net/bnxt/bnxt_rxr.c
@@ -917,17 +917,17 @@  uint16_t bnxt_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 		goto done;
 	}
 
-	rte_compiler_barrier();
+	/* Ring the completion queue doorbell. */
+	bnxt_db_cq(cpr);
+
+	/* Ring the receive descriptor doorbell. */
 	if (rx_raw_prod != rxr->rx_raw_prod)
 		bnxt_db_write(&rxr->rx_db, rxr->rx_raw_prod);
 
-	rte_compiler_barrier();
 	/* Ring the AGG ring DB */
 	if (ag_raw_prod != rxr->ag_raw_prod)
 		bnxt_db_write(&rxr->ag_db, rxr->ag_raw_prod);
 
-	bnxt_db_cq(cpr);
-
 	/* Attempt to alloc Rx buf in case of a previous allocation failure. */
 	if (rc == -ENOMEM) {
 		int i = RING_NEXT(rx_raw_prod);