When packets are filtered by Tx callback, they return value
needs to include those packets; otherwise the application will
do a duplicate free of those mbufs.
The example would be application that sent a burst of 8 packets,
and 2 were filtered but the PMD was busy and could not send any.
The result should be a return value of 2 and mbufs 0..1 should
be freed and 2..7 should be untouched and up to application to
resend or drop.
Original buggy code would return 0 and 0..1 would be freed
2..7 would be unused. Application would then try and drop
or resend an already freed mbuf.
Bugzilla ID: 1816
Fixes: 4dc294158cac ("ethdev: support optional Rx and Tx callbacks")
Cc: [email protected]
Signed-off-by: Stephen Hemminger <[email protected]>
---
lib/ethdev/rte_ethdev.h | 47 ++++++++++++++++++++++++++++++-----------
1 file changed, 35 insertions(+), 12 deletions(-)
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index a66c2abbdb..d2cfe390f9 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -6714,6 +6714,10 @@ rte_eth_tx_burst(uint16_t port_id, uint16_t queue_id,
}
#endif
+ uint16_t requested_pkts = nb_pkts;
+ uint16_t filtered_pkts = 0;
+ rte_mbuf_history_mark_bulk(tx_pkts, nb_pkts, RTE_MBUF_HISTORY_OP_TX);
+
#ifdef RTE_ETHDEV_RXTX_CALLBACKS
{
void *cb;
@@ -6727,22 +6731,41 @@ rte_eth_tx_burst(uint16_t port_id, uint16_t queue_id,
cb = rte_atomic_load_explicit(&p->txq.clbk[queue_id],
rte_memory_order_relaxed);
if (unlikely(cb != NULL))
- nb_pkts = rte_eth_call_tx_callbacks(port_id, queue_id,
- tx_pkts, nb_pkts, cb);
+ filtered_pkts = nb_pkts -
+ rte_eth_call_tx_callbacks(port_id, queue_id,
tx_pkts, nb_pkts, cb);
}
#endif
- uint16_t requested_pkts = nb_pkts;
- rte_mbuf_history_mark_bulk(tx_pkts, nb_pkts, RTE_MBUF_HISTORY_OP_TX);
-
- nb_pkts = p->tx_pkt_burst(qd, tx_pkts, nb_pkts);
-
- if (requested_pkts > nb_pkts)
- rte_mbuf_history_mark_bulk(tx_pkts + nb_pkts,
- requested_pkts - nb_pkts,
RTE_MBUF_HISTORY_OP_TX_BUSY);
+ uint16_t sent_pkts = p->tx_pkt_burst(qd, tx_pkts, nb_pkts -
filtered_pkts);
+ uint16_t result_pkts = sent_pkts + filtered_pkts;
+
+ if (unlikely(result_pkts < requested_pkts)) {
+ uint16_t unsent_pkts = requested_pkts - result_pkts;
+
+ if (unlikely(filtered_pkts > 0)) {
+ /* Need to reshuffle packet list so that unsent packets
are
+ * after the return value
+ *
+ * Original: MMMMMM
+ * Filter: MMMMMF filtered = 1
+ * Tx_burst: SSSUUF sent = 3 unsent = 2
+ *
+ * Return: SSSFUU
+ * return from tx_burst is 4
+ */
+ memmove(tx_pkts + result_pkts, tx_pkts + sent_pkts,
+ unsent_pkts * sizeof(struct rte_mbuf *));
+
+ /* Tx filter process does not drop the packets until
here */
+ rte_pktmbuf_free_bulk(tx_pkts + sent_pkts,
filtered_pkts);
+ }
+
+ rte_mbuf_history_mark_bulk(tx_pkts + result_pkts, unsent_pkts,
+ RTE_MBUF_HISTORY_OP_TX_BUSY);
+ }
- rte_ethdev_trace_tx_burst(port_id, queue_id, (void **)tx_pkts, nb_pkts);
- return nb_pkts;
+ rte_ethdev_trace_tx_burst(port_id, queue_id, (void **)tx_pkts,
result_pkts);
+ return result_pkts;
}
/**
--
2.51.0
