[PATCH v5 5/6] net/null: replace rte atomics with GCC builtin atomics

[Tyler Retzlaff]

Replace the use of rte_atomic.h types and functions, instead use GCC
supplied C++11 memory model builtins.

Signed-off-by: Tyler Retzlaff <roret...@linux.microsoft.com>
Acked-by: Morten Brørup <m...@smartsharesystems.com>
---
 drivers/net/null/rte_eth_null.c | 28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/drivers/net/null/rte_eth_null.c b/drivers/net/null/rte_eth_null.c
index 47d9554..31081af 100644
--- a/drivers/net/null/rte_eth_null.c
+++ b/drivers/net/null/rte_eth_null.c
@@ -37,8 +37,8 @@ struct null_queue {
        struct rte_mempool *mb_pool;
        struct rte_mbuf *dummy_packet;
 
-       rte_atomic64_t rx_pkts;
-       rte_atomic64_t tx_pkts;
+       uint64_t rx_pkts;
+       uint64_t tx_pkts;
 };
 
 struct pmd_options {
@@ -101,7 +101,8 @@ struct pmd_internals {
                bufs[i]->port = h->internals->port_id;
        }
 
-       rte_atomic64_add(&(h->rx_pkts), i);
+       /* NOTE: review for potential ordering optimization */
+       __atomic_fetch_add(&h->rx_pkts, i, __ATOMIC_SEQ_CST);
 
        return i;
 }
@@ -128,7 +129,8 @@ struct pmd_internals {
                bufs[i]->port = h->internals->port_id;
        }
 
-       rte_atomic64_add(&(h->rx_pkts), i);
+       /* NOTE: review for potential ordering optimization */
+       __atomic_fetch_add(&h->rx_pkts, i, __ATOMIC_SEQ_CST);
 
        return i;
 }
@@ -152,7 +154,8 @@ struct pmd_internals {
        for (i = 0; i < nb_bufs; i++)
                rte_pktmbuf_free(bufs[i]);
 
-       rte_atomic64_add(&(h->tx_pkts), i);
+       /* NOTE: review for potential ordering optimization */
+       __atomic_fetch_add(&h->tx_pkts, i, __ATOMIC_SEQ_CST);
 
        return i;
 }
@@ -174,7 +177,8 @@ struct pmd_internals {
                rte_pktmbuf_free(bufs[i]);
        }
 
-       rte_atomic64_add(&(h->tx_pkts), i);
+       /* NOTE: review for potential ordering optimization */
+       __atomic_fetch_add(&h->tx_pkts, i, __ATOMIC_SEQ_CST);
 
        return i;
 }
@@ -316,8 +320,9 @@ struct pmd_internals {
                        RTE_MIN(dev->data->nb_rx_queues,
                                RTE_DIM(internal->rx_null_queues)));
        for (i = 0; i < num_stats; i++) {
+               /* NOTE: review for atomic access */
                igb_stats->q_ipackets[i] =
-                       internal->rx_null_queues[i].rx_pkts.cnt;
+                       internal->rx_null_queues[i].rx_pkts;
                rx_total += igb_stats->q_ipackets[i];
        }
 
@@ -325,8 +330,9 @@ struct pmd_internals {
                        RTE_MIN(dev->data->nb_tx_queues,
                                RTE_DIM(internal->tx_null_queues)));
        for (i = 0; i < num_stats; i++) {
+               /* NOTE: review for atomic access */
                igb_stats->q_opackets[i] =
-                       internal->tx_null_queues[i].tx_pkts.cnt;
+                       internal->tx_null_queues[i].tx_pkts;
                tx_total += igb_stats->q_opackets[i];
        }
 
@@ -347,9 +353,11 @@ struct pmd_internals {
 
        internal = dev->data->dev_private;
        for (i = 0; i < RTE_DIM(internal->rx_null_queues); i++)
-               internal->rx_null_queues[i].rx_pkts.cnt = 0;
+               /* NOTE: review for atomic access */
+               internal->rx_null_queues[i].rx_pkts = 0;
        for (i = 0; i < RTE_DIM(internal->tx_null_queues); i++)
-               internal->tx_null_queues[i].tx_pkts.cnt = 0;
+               /* NOTE: review for atomic access */
+               internal->tx_null_queues[i].tx_pkts = 0;
 
        return 0;
 }
-- 
1.8.3.1