[dpdk-dev] [PATCH 2/6] net/sfc: make Tx free threshold check datapath specific

[Andrew Rybchenko <arybchenko@solarflare.com>]

EFX_TXQ_LIMIT is libefx-specifics and it should not be used
for other Tx datapaths implementations (e.g. EF10 native).

EF10 native Tx datapath has its own understanding of the maximum
TxQ fill level imposed by EvQ clear strategy and space reserved
for Tx error and flush events.

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Andy Moreton <amoreton@solarflare.com>
---
 drivers/net/sfc/sfc_dp_tx.h   | 17 +++++++++++++++++
 drivers/net/sfc/sfc_ef10_tx.c | 15 +++++++++++++++
 drivers/net/sfc/sfc_tx.c      | 39 +++++++++++++++++++++++++++++++--------
 3 files changed, 63 insertions(+), 8 deletions(-)

diff --git a/drivers/net/sfc/sfc_dp_tx.h b/drivers/net/sfc/sfc_dp_tx.h
index 94d1b10..32d7681 100644
--- a/drivers/net/sfc/sfc_dp_tx.h
+++ b/drivers/net/sfc/sfc_dp_tx.h
@@ -78,6 +78,22 @@ struct sfc_dp_tx_qcreate_info {
 };
 
 /**
+ * Get size of transmit and event queue rings by the number of Tx
+ * descriptors.
+ *
+ * @param nb_tx_desc		Number of Tx descriptors
+ * @param txq_entries		Location for number of Tx ring entries
+ * @param evq_entries		Location for number of event ring entries
+ * @param txq_max_fill_level	Location for maximum Tx ring fill level
+ *
+ * @return 0 or positive errno.
+ */
+typedef int (sfc_dp_tx_qsize_up_rings_t)(uint16_t nb_tx_desc,
+					 unsigned int *txq_entries,
+					 unsigned int *evq_entries,
+					 unsigned int *txq_max_fill_level);
+
+/**
  * Allocate and initialize datapath transmit queue.
  *
  * @param port_id	The port identifier
@@ -144,6 +160,7 @@ struct sfc_dp_tx {
 #define SFC_DP_TX_FEAT_MULTI_PROCESS	0x8
 #define SFC_DP_TX_FEAT_MULTI_POOL	0x10
 #define SFC_DP_TX_FEAT_REFCNT		0x20
+	sfc_dp_tx_qsize_up_rings_t	*qsize_up_rings;
 	sfc_dp_tx_qcreate_t		*qcreate;
 	sfc_dp_tx_qdestroy_t		*qdestroy;
 	sfc_dp_tx_qstart_t		*qstart;
diff --git a/drivers/net/sfc/sfc_ef10_tx.c b/drivers/net/sfc/sfc_ef10_tx.c
index 0454e79..ab3334a 100644
--- a/drivers/net/sfc/sfc_ef10_tx.c
+++ b/drivers/net/sfc/sfc_ef10_tx.c
@@ -487,6 +487,19 @@ sfc_ef10_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 }
 
 
+static sfc_dp_tx_qsize_up_rings_t sfc_ef10_tx_qsize_up_rings;
+static int
+sfc_ef10_tx_qsize_up_rings(uint16_t nb_tx_desc,
+			   unsigned int *txq_entries,
+			   unsigned int *evq_entries,
+			   unsigned int *txq_max_fill_level)
+{
+	*txq_entries = nb_tx_desc;
+	*evq_entries = nb_tx_desc;
+	*txq_max_fill_level = SFC_EF10_TXQ_LIMIT(*txq_entries);
+	return 0;
+}
+
 static sfc_dp_tx_qcreate_t sfc_ef10_tx_qcreate;
 static int
 sfc_ef10_tx_qcreate(uint16_t port_id, uint16_t queue_id,
@@ -628,6 +641,7 @@ struct sfc_dp_tx sfc_ef10_tx = {
 				  SFC_DP_TX_FEAT_MULTI_POOL |
 				  SFC_DP_TX_FEAT_REFCNT |
 				  SFC_DP_TX_FEAT_MULTI_PROCESS,
+	.qsize_up_rings		= sfc_ef10_tx_qsize_up_rings,
 	.qcreate		= sfc_ef10_tx_qcreate,
 	.qdestroy		= sfc_ef10_tx_qdestroy,
 	.qstart			= sfc_ef10_tx_qstart,
@@ -644,6 +658,7 @@ struct sfc_dp_tx sfc_ef10_simple_tx = {
 		.type		= SFC_DP_TX,
 	},
 	.features		= SFC_DP_TX_FEAT_MULTI_PROCESS,
+	.qsize_up_rings		= sfc_ef10_tx_qsize_up_rings,
 	.qcreate		= sfc_ef10_tx_qcreate,
 	.qdestroy		= sfc_ef10_tx_qdestroy,
 	.qstart			= sfc_ef10_tx_qstart,
diff --git a/drivers/net/sfc/sfc_tx.c b/drivers/net/sfc/sfc_tx.c
index d1320f4..3c9a6e9 100644
--- a/drivers/net/sfc/sfc_tx.c
+++ b/drivers/net/sfc/sfc_tx.c
@@ -57,7 +57,7 @@
 #define SFC_TX_QFLUSH_POLL_ATTEMPTS	(2000)
 
 static int
-sfc_tx_qcheck_conf(struct sfc_adapter *sa, uint16_t nb_tx_desc,
+sfc_tx_qcheck_conf(struct sfc_adapter *sa, unsigned int txq_max_fill_level,
 		   const struct rte_eth_txconf *tx_conf)
 {
 	unsigned int flags = tx_conf->txq_flags;
@@ -69,10 +69,10 @@ sfc_tx_qcheck_conf(struct sfc_adapter *sa, uint16_t nb_tx_desc,
 		rc = EINVAL;
 	}
 
-	if (tx_conf->tx_free_thresh > EFX_TXQ_LIMIT(nb_tx_desc)) {
+	if (tx_conf->tx_free_thresh > txq_max_fill_level) {
 		sfc_err(sa,
 			"TxQ free threshold too large: %u vs maximum %u",
-			tx_conf->tx_free_thresh, EFX_TXQ_LIMIT(nb_tx_desc));
+			tx_conf->tx_free_thresh, txq_max_fill_level);
 		rc = EINVAL;
 	}
 
@@ -145,6 +145,9 @@ sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
 	     const struct rte_eth_txconf *tx_conf)
 {
 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
+	unsigned int txq_entries;
+	unsigned int evq_entries;
+	unsigned int txq_max_fill_level;
 	struct sfc_txq_info *txq_info;
 	struct sfc_evq *evq;
 	struct sfc_txq *txq;
@@ -153,18 +156,23 @@ sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
 
 	sfc_log_init(sa, "TxQ = %u", sw_index);
 
-	rc = sfc_tx_qcheck_conf(sa, nb_tx_desc, tx_conf);
+	rc = sa->dp_tx->qsize_up_rings(nb_tx_desc, &txq_entries, &evq_entries,
+				       &txq_max_fill_level);
+	if (rc != 0)
+		goto fail_size_up_rings;
+
+	rc = sfc_tx_qcheck_conf(sa, txq_max_fill_level, tx_conf);
 	if (rc != 0)
 		goto fail_bad_conf;
 
 	SFC_ASSERT(sw_index < sa->txq_count);
 	txq_info = &sa->txq_info[sw_index];
 
-	SFC_ASSERT(nb_tx_desc <= sa->txq_max_entries);
-	txq_info->entries = nb_tx_desc;
+	SFC_ASSERT(txq_entries <= sa->txq_max_entries);
+	txq_info->entries = txq_entries;
 
 	rc = sfc_ev_qinit(sa, SFC_EVQ_TYPE_TX, sw_index,
-			  txq_info->entries, socket_id, &evq);
+			  evq_entries, socket_id, &evq);
 	if (rc != 0)
 		goto fail_ev_qinit;
 
@@ -193,7 +201,7 @@ sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
 	info.txq_entries = txq_info->entries;
 	info.dma_desc_size_max = encp->enc_tx_dma_desc_size_max;
 	info.txq_hw_ring = txq->mem.esm_base;
-	info.evq_entries = txq_info->entries;
+	info.evq_entries = evq_entries;
 	info.evq_hw_ring = evq->mem.esm_base;
 	info.hw_index = txq->hw_index;
 	info.mem_bar = sa->mem_bar.esb_base;
@@ -226,6 +234,7 @@ sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
 	txq_info->entries = 0;
 
 fail_bad_conf:
+fail_size_up_rings:
 	sfc_log_init(sa, "failed (TxQ = %u, rc = %d)", sw_index, rc);
 	return rc;
 }
@@ -865,6 +874,19 @@ sfc_txq_by_dp_txq(const struct sfc_dp_txq *dp_txq)
 	return txq;
 }
 
+static sfc_dp_tx_qsize_up_rings_t sfc_efx_tx_qsize_up_rings;
+static int
+sfc_efx_tx_qsize_up_rings(uint16_t nb_tx_desc,
+			  unsigned int *txq_entries,
+			  unsigned int *evq_entries,
+			  unsigned int *txq_max_fill_level)
+{
+	*txq_entries = nb_tx_desc;
+	*evq_entries = nb_tx_desc;
+	*txq_max_fill_level = EFX_TXQ_LIMIT(*txq_entries);
+	return 0;
+}
+
 static sfc_dp_tx_qcreate_t sfc_efx_tx_qcreate;
 static int
 sfc_efx_tx_qcreate(uint16_t port_id, uint16_t queue_id,
@@ -1040,6 +1062,7 @@ struct sfc_dp_tx sfc_efx_tx = {
 				  SFC_DP_TX_FEAT_MULTI_POOL |
 				  SFC_DP_TX_FEAT_REFCNT |
 				  SFC_DP_TX_FEAT_MULTI_SEG,
+	.qsize_up_rings		= sfc_efx_tx_qsize_up_rings,
 	.qcreate		= sfc_efx_tx_qcreate,
 	.qdestroy		= sfc_efx_tx_qdestroy,
 	.qstart			= sfc_efx_tx_qstart,
-- 
2.7.4