net/sfc: add Rx datapath method to get pushed buffers count

The information about the number of pushed Rx buffers is required
for counter Rx queue to know when to give credits to counter
stream.

Signed-off-by: Igor Romanov <igor.romanov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>
Reviewed-by: Ivan Malov <ivan.malov@oktetlabs.ru>

diff --git a/drivers/net/sfc/sfc_dp_rx.h b/drivers/net/sfc/sfc_dp_rx.h
index 3f6857b..b6c4408 100644 (file)
--- a/drivers/net/sfc/sfc_dp_rx.h
+++ b/drivers/net/sfc/sfc_dp_rx.h
@@ -204,6 +204,9 @@ typedef int (sfc_dp_rx_intr_enable_t)(struct sfc_dp_rxq *dp_rxq);
 /** Disable Rx interrupts */
 typedef int (sfc_dp_rx_intr_disable_t)(struct sfc_dp_rxq *dp_rxq);
 
+/** Get number of pushed Rx buffers */
+typedef unsigned int (sfc_dp_rx_get_pushed_t)(struct sfc_dp_rxq *dp_rxq);
+
 /** Receive datapath definition */
 struct sfc_dp_rx {
        struct sfc_dp                           dp;
@@ -238,6 +241,7 @@ struct sfc_dp_rx {
        sfc_dp_rx_qdesc_status_t                *qdesc_status;
        sfc_dp_rx_intr_enable_t                 *intr_enable;
        sfc_dp_rx_intr_disable_t                *intr_disable;
+       sfc_dp_rx_get_pushed_t                  *get_pushed;
        eth_rx_burst_t                          pkt_burst;
 };
 

diff --git a/drivers/net/sfc/sfc_ef100_rx.c b/drivers/net/sfc/sfc_ef100_rx.c
index 8b90463..10c74aa 100644 (file)
--- a/drivers/net/sfc/sfc_ef100_rx.c
+++ b/drivers/net/sfc/sfc_ef100_rx.c
@@ -892,6 +892,20 @@ sfc_ef100_rx_intr_disable(struct sfc_dp_rxq *dp_rxq)
        return 0;
 }
 
+static sfc_dp_rx_get_pushed_t sfc_ef100_rx_get_pushed;
+static unsigned int
+sfc_ef100_rx_get_pushed(struct sfc_dp_rxq *dp_rxq)
+{
+       struct sfc_ef100_rxq *rxq = sfc_ef100_rxq_by_dp_rxq(dp_rxq);
+
+       /*
+        * The datapath keeps track only of added descriptors, since
+        * the number of pushed descriptors always equals the number
+        * of added descriptors due to enforced alignment.
+        */
+       return rxq->added;
+}
+
 struct sfc_dp_rx sfc_ef100_rx = {
        .dp = {
                .name           = SFC_KVARG_DATAPATH_EF100,
@@ -919,5 +933,6 @@ struct sfc_dp_rx sfc_ef100_rx = {
        .qdesc_status           = sfc_ef100_rx_qdesc_status,
        .intr_enable            = sfc_ef100_rx_intr_enable,
        .intr_disable           = sfc_ef100_rx_intr_disable,
+       .get_pushed             = sfc_ef100_rx_get_pushed,
        .pkt_burst              = sfc_ef100_recv_pkts,
 };

diff --git a/drivers/net/sfc/sfc_rx.c b/drivers/net/sfc/sfc_rx.c
index 0532f77..f6a8ac6 100644 (file)
--- a/drivers/net/sfc/sfc_rx.c
+++ b/drivers/net/sfc/sfc_rx.c
@@ -53,6 +53,15 @@ sfc_rx_qflush_failed(struct sfc_rxq_info *rxq_info)
        rxq_info->state &= ~SFC_RXQ_FLUSHING;
 }
 
+/* This returns the running counter, which is not bounded by ring size */
+unsigned int
+sfc_rx_get_pushed(struct sfc_adapter *sa, struct sfc_dp_rxq *dp_rxq)
+{
+       SFC_ASSERT(sa->priv.dp_rx->get_pushed != NULL);
+
+       return sa->priv.dp_rx->get_pushed(dp_rxq);
+}
+
 static int
 sfc_efx_rx_qprime(struct sfc_efx_rxq *rxq)
 {

diff --git a/drivers/net/sfc/sfc_rx.h b/drivers/net/sfc/sfc_rx.h
index e5a6fde..4ab5139 100644 (file)
--- a/drivers/net/sfc/sfc_rx.h
+++ b/drivers/net/sfc/sfc_rx.h
@@ -145,6 +145,9 @@ uint64_t sfc_rx_get_queue_offload_caps(struct sfc_adapter *sa);
 void sfc_rx_qflush_done(struct sfc_rxq_info *rxq_info);
 void sfc_rx_qflush_failed(struct sfc_rxq_info *rxq_info);
 
+unsigned int sfc_rx_get_pushed(struct sfc_adapter *sa,
+                              struct sfc_dp_rxq *dp_rxq);
+
 int sfc_rx_hash_init(struct sfc_adapter *sa);
 void sfc_rx_hash_fini(struct sfc_adapter *sa);
 int sfc_rx_hf_rte_to_efx(struct sfc_adapter *sa, uint64_t rte,