[PATCH v3 15/27] net/netvsc: replace rte_atomic32 with stdatomic

[Stephen Hemminger]

Change the rndis transaction id and buffer usage to use
stdatomic functions.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/net/netvsc/hn_rndis.c | 28 +++++++++++++++++++---------
 drivers/net/netvsc/hn_rxtx.c  | 12 +++++++-----
 drivers/net/netvsc/hn_var.h   |  6 +++---
 3 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/drivers/net/netvsc/hn_rndis.c b/drivers/net/netvsc/hn_rndis.c
index 7c54eebcef..4b1d3d5539 100644
--- a/drivers/net/netvsc/hn_rndis.c
+++ b/drivers/net/netvsc/hn_rndis.c
@@ -17,7 +17,7 @@
 #include <rte_string_fns.h>
 #include <rte_memzone.h>
 #include <rte_malloc.h>
-#include <rte_atomic.h>
+#include <rte_stdatomic.h>
 #include <rte_alarm.h>
 #include <rte_branch_prediction.h>
 #include <rte_ether.h>
@@ -59,7 +59,8 @@ hn_rndis_rid(struct hn_data *hv)
 	uint32_t rid;
 
 	do {
-		rid = rte_atomic32_add_return(&hv->rndis_req_id, 1);
+		rid = rte_atomic_fetch_add_explicit(&hv->rndis_req_id, 1,
+						    rte_memory_order_seq_cst);
 	} while (rid == 0);
 
 	return rid;
@@ -357,12 +358,14 @@ void hn_rndis_receive_response(struct hn_data *hv,
 	memcpy(hv->rndis_resp, data, len);
 
 	/* make sure response copied before update */
-	rte_smp_wmb();
-
-	if (rte_atomic32_cmpset(&hv->rndis_pending, hdr->rid, 0) == 0) {
+	uint32_t expected = hdr->rid;
+	if (!rte_atomic_compare_exchange_strong_explicit(&hv->rndis_pending,
+							 &expected, 0,
+							 rte_memory_order_release,
+							 rte_memory_order_relaxed)) {
 		PMD_DRV_LOG(NOTICE,
 			    "received id %#x pending id %#x",
-			    hdr->rid, (uint32_t)hv->rndis_pending);
+			    hdr->rid, expected);
 	}
 }
 
@@ -388,8 +391,11 @@ static int hn_rndis_exec1(struct hn_data *hv,
 		return -EINVAL;
 	}
 
+	uint32_t expected = 0;
 	if (comp != NULL &&
-	    rte_atomic32_cmpset(&hv->rndis_pending, 0, rid) == 0) {
+	    !rte_atomic_compare_exchange_strong_explicit(
+		    &hv->rndis_pending, &expected, rid,
+		    rte_memory_order_acquire, rte_memory_order_relaxed)) {
 		PMD_DRV_LOG(ERR,
 			    "Request already pending");
 		return -EBUSY;
@@ -405,7 +411,8 @@ static int hn_rndis_exec1(struct hn_data *hv,
 		time_t start = time(NULL);
 
 		/* Poll primary channel until response received */
-		while (hv->rndis_pending == rid) {
+		while (rte_atomic_load_explicit(&hv->rndis_pending,
+						rte_memory_order_acquire) == rid) {
 			if (hv->closed)
 				return -ENETDOWN;
 
@@ -413,7 +420,10 @@ static int hn_rndis_exec1(struct hn_data *hv,
 				PMD_DRV_LOG(ERR,
 					    "RNDIS response timed out");
 
-				rte_atomic32_cmpset(&hv->rndis_pending, rid, 0);
+				expected = rid;
+				rte_atomic_compare_exchange_strong_explicit(
+					&hv->rndis_pending, &expected, 0,
+					rte_memory_order_release, rte_memory_order_relaxed);
 				return -ETIMEDOUT;
 			}
 
diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
index 0d770d1b25..6f536610f2 100644
--- a/drivers/net/netvsc/hn_rxtx.c
+++ b/drivers/net/netvsc/hn_rxtx.c
@@ -17,7 +17,7 @@
 #include <rte_string_fns.h>
 #include <rte_memzone.h>
 #include <rte_malloc.h>
-#include <rte_atomic.h>
+#include <rte_stdatomic.h>
 #include <rte_bitmap.h>
 #include <rte_branch_prediction.h>
 #include <rte_ether.h>
@@ -558,7 +558,8 @@ static void hn_rx_buf_free_cb(void *buf __rte_unused, void *opaque)
 	struct hn_rx_queue *rxq = rxb->rxq;
 	struct hn_data *hv = rxq->hv;
 
-	rte_atomic32_dec(&rxq->rxbuf_outstanding);
+	rte_atomic_fetch_sub_explicit(&rxq->rxbuf_outstanding, 1,
+				      rte_memory_order_release);
 	hn_nvs_ack_rxbuf(hv, rxb->chan, rxb->xactid);
 }
 
@@ -602,8 +603,8 @@ static void hn_rxpkt(struct hn_rx_queue *rxq, struct hn_rx_bufinfo *rxb,
 	 * some space available in receive area for later packets.
 	 */
 	if (hv->rx_extmbuf_enable && dlen > hv->rx_copybreak &&
-	    (uint32_t)rte_atomic32_read(&rxq->rxbuf_outstanding) <
-			hv->rxbuf_section_cnt / 2) {
+	    rte_atomic_load_explicit(&rxq->rxbuf_outstanding,
+				     rte_memory_order_relaxed) < hv->rxbuf_section_cnt / 2) {
 		struct rte_mbuf_ext_shared_info *shinfo;
 		const void *rxbuf;
 		rte_iova_t iova;
@@ -619,7 +620,8 @@ static void hn_rxpkt(struct hn_rx_queue *rxq, struct hn_rx_bufinfo *rxb,
 
 		/* shinfo is already set to 1 by the caller */
 		if (rte_mbuf_ext_refcnt_update(shinfo, 1) == 2)
-			rte_atomic32_inc(&rxq->rxbuf_outstanding);
+			rte_atomic_fetch_add_explicit(&rxq->rxbuf_outstanding, 1,
+						      rte_memory_order_acquire);
 
 		rte_pktmbuf_attach_extbuf(m, data, iova,
 					  dlen + headroom, shinfo);
diff --git a/drivers/net/netvsc/hn_var.h b/drivers/net/netvsc/hn_var.h
index ef55dee28e..b0929de790 100644
--- a/drivers/net/netvsc/hn_var.h
+++ b/drivers/net/netvsc/hn_var.h
@@ -85,7 +85,7 @@ struct hn_rx_queue {
 
 	void *event_buf;
 	struct hn_rx_bufinfo *rxbuf_info;
-	rte_atomic32_t  rxbuf_outstanding;
+	RTE_ATOMIC(uint32_t) rxbuf_outstanding;
 };
 
 
@@ -166,8 +166,8 @@ struct hn_data {
 	uint32_t	rndis_agg_pkts;
 	uint32_t	rndis_agg_align;
 
-	volatile uint32_t  rndis_pending;
-	rte_atomic32_t	rndis_req_id;
+	RTE_ATOMIC(uint32_t) rndis_pending;
+	RTE_ATOMIC(uint32_t) rndis_req_id;
 	uint8_t		rndis_resp[256];
 
 	uint32_t	rss_hash;
-- 
2.53.0