qede: Postpone reallocation until NAPI end

During Rx flow driver allocates a replacement buffer each time
it consumes an Rx buffer. Failing to do so, it would consume the
currently processed buffer and re-post it on the ring.
As a result, the Rx ring is always completely full [from driver POV].

We now allow the Rx ring to shorten by doing the re-allocations
at the end of the NAPI run. The only limitation is that we still want to
make sure each time we reallocate that we'd still have sufficient
elements in the Rx ring to guarantee that FW would be able to post
additional data and trigger an interrupt.

Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/net/ethernet/qlogic/qede/qede.h b/drivers/net/ethernet/qlogic/qede/qede.h
index ab49263c9d43..1c5aac4b6139 100644
--- a/drivers/net/ethernet/qlogic/qede/qede.h
+++ b/drivers/net/ethernet/qlogic/qede/qede.h
@@ -280,7 +280,7 @@ struct qede_rx_queue {
         u16 sw_rx_cons;
         u16 sw_rx_prod;
 
-        u16 num_rx_buffers; /* Slowpath */
+        u16 filled_buffers;
         u8 data_direction;
         u8 rxq_id;
 
@@ -293,6 +293,9 @@ struct qede_rx_queue {
         struct qed_chain rx_bd_ring;
         struct qed_chain rx_comp_ring ____cacheline_aligned;
 
+        /* Used once per each NAPI run */
+        u16 num_rx_buffers;
+
         /* GRO */
         struct qede_agg_info tpa_info[ETH_TPA_MAX_AGGS_NUM];
 
@@ -414,7 +417,7 @@ netdev_features_t qede_features_check(struct sk_buff *skb,
                                       struct net_device *dev,
                                       netdev_features_t features);
 void qede_tx_log_print(struct qede_dev *edev, struct qede_fastpath *fp);
-int qede_alloc_rx_buffer(struct qede_rx_queue *rxq);
+int qede_alloc_rx_buffer(struct qede_rx_queue *rxq, bool allow_lazy);
 int qede_free_tx_pkt(struct qede_dev *edev,
                      struct qede_tx_queue *txq, int *len);
 int qede_poll(struct napi_struct *napi, int budget);