net/sfc: introduce descriptor space check in Tx prepare

Add descriptor space check to Tx prepare function to inform a caller
that a packet that needs more than maximum Tx descriptors of a queue
can not be sent.

Signed-off-by: Igor Romanov <igor.romanov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
This commit is contained in:
Igor Romanov 2019-04-02 10:28:40 +01:00 committed by Ferruh Yigit
parent a3895ef38c
commit f7a66f9365
3 changed files with 41 additions and 3 deletions

View File

@ -196,8 +196,13 @@ const struct sfc_dp_tx *sfc_dp_tx_by_dp_txq(const struct sfc_dp_txq *dp_txq);
static inline int
sfc_dp_tx_prepare_pkt(struct rte_mbuf *m,
uint32_t tso_tcp_header_offset_limit)
uint32_t tso_tcp_header_offset_limit,
unsigned int max_fill_level,
unsigned int nb_tso_descs,
unsigned int nb_vlan_descs)
{
unsigned int descs_required = m->nb_segs;
#ifdef RTE_LIBRTE_SFC_EFX_DEBUG
int ret;
@ -214,11 +219,35 @@ sfc_dp_tx_prepare_pkt(struct rte_mbuf *m,
if (m->ol_flags & PKT_TX_TCP_SEG) {
unsigned int tcph_off = m->l2_len + m->l3_len;
unsigned int header_len = tcph_off + m->l4_len;
if (unlikely(tcph_off > tso_tcp_header_offset_limit))
return EINVAL;
descs_required += nb_tso_descs;
/*
* Extra descriptor that is required when a packet header
* is separated from remaining content of the first segment.
*/
if (rte_pktmbuf_data_len(m) > header_len)
descs_required++;
}
/*
* The number of VLAN descriptors is added regardless of requested
* VLAN offload since VLAN is sticky and sending packet without VLAN
* insertion may require VLAN descriptor to reset the sticky to 0.
*/
descs_required += nb_vlan_descs;
/*
* Max fill level must be sufficient to hold all required descriptors
* to send the packet entirely.
*/
if (descs_required > max_fill_level)
return ENOBUFS;
return 0;
}

View File

@ -349,7 +349,9 @@ sfc_ef10_prepare_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
}
#endif
ret = sfc_dp_tx_prepare_pkt(m,
txq->tso_tcp_header_offset_limit);
txq->tso_tcp_header_offset_limit,
txq->max_fill_level,
SFC_EF10_TSO_OPT_DESCS_NUM, 0);
if (unlikely(ret != 0)) {
rte_errno = ret;
break;

View File

@ -709,8 +709,15 @@ sfc_efx_prepare_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
for (i = 0; i < nb_pkts; i++) {
int ret;
/*
* EFX Tx datapath may require extra VLAN descriptor if VLAN
* insertion offload is requested regardless the offload
* requested/supported.
*/
ret = sfc_dp_tx_prepare_pkt(tx_pkts[i],
encp->enc_tx_tso_tcp_header_offset_limit);
encp->enc_tx_tso_tcp_header_offset_limit,
txq->max_fill_level, EFX_TX_FATSOV2_OPT_NDESCS,
1);
if (unlikely(ret != 0)) {
rte_errno = ret;
break;