net: thunderx: Fix transmit queue timeout issue
Transmit queue timeout issue is seen in two cases
- Due to a race condition btw setting stop_queue at xmit()
and checking for stopped_queue in NAPI poll routine, at times
transmission from a SQ comes to a halt. This is fixed
by using barriers and also added a check for SQ free descriptors,
incase SQ is stopped and there are only CQE_RX i.e no CQE_TX.
- Contrary to an assumption, a HW errata where HW doesn't stop transmission
even though there are not enough CQEs available for a CQE_TX is
not fixed in T88 pass 2.x. This results in a Qset error with
'CQ_WR_FULL' stalling transmission. This is fixed by adjusting
RXQ's RED levels for CQ level such that there is always enough
space left for CQE_TXs.
Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index 7b336cd..d2ac133 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -1190,30 +1190,12 @@ static int nicvf_sq_append_tso(struct nicvf *nic, struct snd_queue *sq,
}
/* Append an skb to a SQ for packet transfer. */
-int nicvf_sq_append_skb(struct nicvf *nic, struct sk_buff *skb)
+int nicvf_sq_append_skb(struct nicvf *nic, struct snd_queue *sq,
+ struct sk_buff *skb, u8 sq_num)
{
int i, size;
int subdesc_cnt, tso_sqe = 0;
- int sq_num, qentry;
- struct queue_set *qs;
- struct snd_queue *sq;
-
- sq_num = skb_get_queue_mapping(skb);
- if (sq_num >= MAX_SND_QUEUES_PER_QS) {
- /* Get secondary Qset's SQ structure */
- i = sq_num / MAX_SND_QUEUES_PER_QS;
- if (!nic->snicvf[i - 1]) {
- netdev_warn(nic->netdev,
- "Secondary Qset#%d's ptr not initialized\n",
- i - 1);
- return 1;
- }
- nic = (struct nicvf *)nic->snicvf[i - 1];
- sq_num = sq_num % MAX_SND_QUEUES_PER_QS;
- }
-
- qs = nic->qs;
- sq = &qs->sq[sq_num];
+ int qentry;
subdesc_cnt = nicvf_sq_subdesc_required(nic, skb);
if (subdesc_cnt > atomic_read(&sq->free_cnt))