From: Joshua Washington <joshwash@google.com>
To: stable@dpdk.org, Junfeng Guo <junfengg@nvidia.com>,
Jeroen de Borst <jeroendb@google.com>,
Rushil Gupta <rushilg@google.com>,
Joshua Washington <joshwash@google.com>
Cc: Ankit Garg <nktgrg@google.com>
Subject: [PATCH 23.11 2/3] net/gve: clean when insufficient Tx descriptors
Date: Tue, 23 Dec 2025 14:30:48 -0800 [thread overview]
Message-ID: <20251223223050.3870080-2-joshwash@google.com> (raw)
In-Reply-To: <20251223223050.3870080-1-joshwash@google.com>
A single packet can technically require more than 32 (free_thresh)
descriptors to send. Count the number of descriptors needed to send out
a packet in DQO Tx, and ensure that there are enough descriptors in the
ring before writing. If there are not enough free descriptors, drop the
packet and increment drop counters.
Fixes: 4022f9999f56 ("net/gve: support basic Tx data path for DQO")
Cc: stable@dpdk.org
Signed-off-by: Joshua Washington <joshwash@google.com>
Reviewed-by: Ankit Garg <nktgrg@google.com>
---
drivers/net/gve/gve_tx_dqo.c | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)
diff --git a/drivers/net/gve/gve_tx_dqo.c b/drivers/net/gve/gve_tx_dqo.c
index a4ba8c3536..8e75e4d570 100644
--- a/drivers/net/gve/gve_tx_dqo.c
+++ b/drivers/net/gve/gve_tx_dqo.c
@@ -74,6 +74,12 @@ gve_tx_clean_dqo(struct gve_tx_queue *txq)
txq->complq_tail = next;
}
+static inline void
+gve_tx_clean_descs_dqo(struct gve_tx_queue *txq, uint16_t nb_descs) {
+ while (--nb_descs)
+ gve_tx_clean_dqo(txq);
+}
+
static uint16_t
gve_tx_pkt_nb_data_descs(struct rte_mbuf *tx_pkt)
{
@@ -96,7 +102,6 @@ gve_tx_burst_dqo(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
struct rte_mbuf **sw_ring;
struct rte_mbuf *tx_pkt;
uint16_t mask, sw_mask;
- uint16_t nb_to_clean;
uint16_t first_sw_id;
const char *reason;
uint16_t nb_tx = 0;
@@ -119,11 +124,9 @@ gve_tx_burst_dqo(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
tx_pkt = tx_pkts[nb_tx];
- if (txq->nb_free <= txq->free_thresh) {
- nb_to_clean = DQO_TX_MULTIPLIER * txq->rs_thresh;
- while (nb_to_clean--)
- gve_tx_clean_dqo(txq);
- }
+ if (txq->nb_free <= txq->free_thresh)
+ gve_tx_clean_descs_dqo(txq, DQO_TX_MULTIPLIER *
+ txq->rs_thresh);
if (txq->nb_free < tx_pkt->nb_segs)
break;
@@ -140,8 +143,16 @@ gve_tx_burst_dqo(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
csum = !!(ol_flags & GVE_TX_CKSUM_OFFLOAD_MASK_DQO);
nb_descs = gve_tx_pkt_nb_data_descs(tx_pkt);
- if (txq->nb_free < nb_descs)
- break;
+
+ /* Clean if there aren't enough descriptors to send the packet. */
+ if (unlikely(txq->nb_free < nb_descs)) {
+ int nb_to_clean = RTE_MAX(DQO_TX_MULTIPLIER * txq->rs_thresh,
+ nb_descs);
+
+ gve_tx_clean_descs_dqo(txq, nb_to_clean);
+ if (txq->nb_free < nb_descs)
+ break;
+ }
do {
if (sw_ring[sw_id] != NULL)
--
2.52.0.351.gbe84eed79e-goog
next prev parent reply other threads:[~2025-12-23 22:30 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-23 22:30 [PATCH 23.11 1/3] net/gve: send whole packet when mbuf is large Joshua Washington
2025-12-23 22:30 ` Joshua Washington [this message]
2025-12-23 22:30 ` [PATCH 23.11 3/3] net/gve: add DQO Tx descriptor limit Joshua Washington
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