diff mbox series

net/mlx5: relax headroom assertion

Message ID 20211228092043.3360072-1-dkozlyuk@nvidia.com (mailing list archive)
State Accepted, archived
Delegated to: Raslan Darawsheh
Headers
Series net/mlx5: relax headroom assertion |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/github-robot: build success github build: passed
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-aarch64-unit-testing success Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS
ci/iol-aarch64-compile-testing success Testing PASS
ci/iol-abi-testing success Testing PASS
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS

Commit Message

Dmitry Kozlyuk Dec. 28, 2021, 9:20 a.m. UTC 
  A debug assertion in Single-Packet Receive Queue (SPRQ) mode
required all Rx mbufs to have a 128 byte headroom,
based on the assumption that rte_pktmbuf_init() sets it.
However, rte_pktmbuf_init() may set a smaller headroom
if the dataroom is insufficient, e.g. this is a natural case
for split buffer segments. The headroom can also be larger.
Only check the headroom size when vectored Rx routines
are used because they rely on it. Relax the assertion
to require sufficient headroom size, not an exact one.

Fixes: a0a45e8af723 ("net/mlx5: configure Rx queue for buffer split")
Cc: viacheslavo@nvidia.com
Cc: stable@dpdk.org

Signed-off-by: Dmitry Kozlyuk <dkozlyuk@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>
---
 drivers/net/mlx5/mlx5_rxq.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Comments

Raslan Darawsheh Jan. 13, 2022, 8:59 a.m. UTC | #1 
Hi,

> -----Original Message-----
> From: Dmitry Kozlyuk <dkozlyuk@nvidia.com>
> Sent: Tuesday, December 28, 2021 11:21 AM
> To: dev@dpdk.org
> Cc: Slava Ovsiienko <viacheslavo@nvidia.com>; stable@dpdk.org; Matan
> Azrad <matan@nvidia.com>
> Subject: [PATCH] net/mlx5: relax headroom assertion
> 
> A debug assertion in Single-Packet Receive Queue (SPRQ) mode required all
> Rx mbufs to have a 128 byte headroom, based on the assumption that
> rte_pktmbuf_init() sets it.
> However, rte_pktmbuf_init() may set a smaller headroom if the dataroom is
> insufficient, e.g. this is a natural case for split buffer segments. The
> headroom can also be larger.
> Only check the headroom size when vectored Rx routines are used because
> they rely on it. Relax the assertion to require sufficient headroom size, not an
> exact one.
> 
> Fixes: a0a45e8af723 ("net/mlx5: configure Rx queue for buffer split")
> Cc: viacheslavo@nvidia.com
> Cc: stable@dpdk.org
> 
> Signed-off-by: Dmitry Kozlyuk <dkozlyuk@nvidia.com>
> Acked-by: Matan Azrad <matan@nvidia.com>

Patch rebased and applied to next-net-mlx,

Kindest regards,
Raslan Darawsheh
diff mbox series

Patch

diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
index f77d42dedf..baf676d3b4 100644
--- a/drivers/net/mlx5/mlx5_rxq.c
+++ b/drivers/net/mlx5/mlx5_rxq.c
@@ -139,6 +139,7 @@  rxq_alloc_elts_sprq(struct mlx5_rxq_ctrl *rxq_ctrl)
 	unsigned int elts_n = mlx5_rxq_mprq_enabled(&rxq_ctrl->rxq) ?
 		(1 << rxq_ctrl->rxq.elts_n) * (1 << rxq_ctrl->rxq.strd_num_n) :
 		(1 << rxq_ctrl->rxq.elts_n);
+	bool has_vec_support = mlx5_rxq_check_vec_support(&rxq_ctrl->rxq) > 0;
 	unsigned int i;
 	int err;
 
@@ -160,8 +161,9 @@  rxq_alloc_elts_sprq(struct mlx5_rxq_ctrl *rxq_ctrl)
 			rte_errno = ENOMEM;
 			goto error;
 		}
-		/* Headroom is reserved by rte_pktmbuf_alloc(). */
-		MLX5_ASSERT(DATA_OFF(buf) == RTE_PKTMBUF_HEADROOM);
+		/* Only vectored Rx routines rely on headroom size. */
+		MLX5_ASSERT(!has_vec_support ||
+			    DATA_OFF(buf) >= RTE_PKTMBUF_HEADROOM);
 		/* Buffer is supposed to be empty. */
 		MLX5_ASSERT(rte_pktmbuf_data_len(buf) == 0);
 		MLX5_ASSERT(rte_pktmbuf_pkt_len(buf) == 0);
@@ -174,7 +176,7 @@  rxq_alloc_elts_sprq(struct mlx5_rxq_ctrl *rxq_ctrl)
 		(*rxq_ctrl->rxq.elts)[i] = buf;
 	}
 	/* If Rx vector is activated. */
-	if (mlx5_rxq_check_vec_support(&rxq_ctrl->rxq) > 0) {
+	if (has_vec_support) {
 		struct mlx5_rxq_data *rxq = &rxq_ctrl->rxq;
 		struct rte_mbuf *mbuf_init = &rxq->fake_mbuf;
 		struct rte_pktmbuf_pool_private *priv =