net/sfc: rely on one desc is one mbuf in simple EF10 Tx reap

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Andy Moreton <amoreton@solarflare.com>
Reviewed-by: David Riddoch <driddoch@solarflare.com>

diff --git a/drivers/net/sfc/sfc_ef10_tx.c b/drivers/net/sfc/sfc_ef10_tx.c
index fdeea2c..da2b5ed 100644 (file)
--- a/drivers/net/sfc/sfc_ef10_tx.c
+++ b/drivers/net/sfc/sfc_ef10_tx.c
@@ -128,14 +128,10 @@ sfc_ef10_tx_get_event(struct sfc_ef10_txq *txq, efx_qword_t *tx_ev)
        return true;
 }
 
-static void
-sfc_ef10_tx_reap(struct sfc_ef10_txq *txq)
+static unsigned int
+sfc_ef10_tx_process_events(struct sfc_ef10_txq *txq)
 {
-       const unsigned int old_read_ptr = txq->evq_read_ptr;
-       const unsigned int ptr_mask = txq->ptr_mask;
-       unsigned int completed = txq->completed;
-       unsigned int pending = completed;
-       const unsigned int curr_done = pending - 1;
+       const unsigned int curr_done = txq->completed - 1;
        unsigned int anew_done = curr_done;
        efx_qword_t tx_ev;
 
@@ -148,7 +144,18 @@ sfc_ef10_tx_reap(struct sfc_ef10_txq *txq)
                /* Update the latest done descriptor */
                anew_done = EFX_QWORD_FIELD(tx_ev, ESF_DZ_TX_DESCR_INDX);
        }
-       pending += (anew_done - curr_done) & ptr_mask;
+       return (anew_done - curr_done) & txq->ptr_mask;
+}
+
+static void
+sfc_ef10_tx_reap(struct sfc_ef10_txq *txq)
+{
+       const unsigned int old_read_ptr = txq->evq_read_ptr;
+       const unsigned int ptr_mask = txq->ptr_mask;
+       unsigned int completed = txq->completed;
+       unsigned int pending = completed;
+
+       pending += sfc_ef10_tx_process_events(txq);
 
        if (pending != completed) {
                do {
@@ -349,6 +356,33 @@ sfc_ef10_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
        return pktp - &tx_pkts[0];
 }
 
+static void
+sfc_ef10_simple_tx_reap(struct sfc_ef10_txq *txq)
+{
+       const unsigned int old_read_ptr = txq->evq_read_ptr;
+       const unsigned int ptr_mask = txq->ptr_mask;
+       unsigned int completed = txq->completed;
+       unsigned int pending = completed;
+
+       pending += sfc_ef10_tx_process_events(txq);
+
+       if (pending != completed) {
+               do {
+                       struct sfc_ef10_tx_sw_desc *txd;
+
+                       txd = &txq->sw_ring[completed & ptr_mask];
+
+                       rte_pktmbuf_free_seg(txd->mbuf);
+               } while (++completed != pending);
+
+               txq->completed = completed;
+       }
+
+       sfc_ef10_ev_qclear(txq->evq_hw_ring, ptr_mask, old_read_ptr,
+                          txq->evq_read_ptr);
+}
+
+
 static uint16_t
 sfc_ef10_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                          uint16_t nb_pkts)
@@ -372,7 +406,7 @@ sfc_ef10_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 
        reap_done = (dma_desc_space < RTE_MAX(txq->free_thresh, nb_pkts));
        if (reap_done) {
-               sfc_ef10_tx_reap(txq);
+               sfc_ef10_simple_tx_reap(txq);
                dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
                                 (added - txq->completed);
        }
@@ -401,7 +435,7 @@ sfc_ef10_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 
 #if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
        if (!reap_done)
-               sfc_ef10_tx_reap(txq);
+               sfc_ef10_simple_tx_reap(txq);
 #endif
 
        return pktp - &tx_pkts[0];