[dpdk-stable] patch 'net/ark: refactor Rx buffer recovery' has been queued to stable release 19.11.9

[Christian Ehrhardt]

Hi,

FYI, your patch has been queued to stable release 19.11.9

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 05/19/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/cpaelzer/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/cpaelzer/dpdk-stable-queue/commit/099ab9bb98acf79008db7fcb86b8dad2664e2a56

Thanks.

Christian Ehrhardt <christian.ehrhardt at canonical.com>

---
>From 099ab9bb98acf79008db7fcb86b8dad2664e2a56 Mon Sep 17 00:00:00 2001
From: Ed Czeck <ed.czeck at atomicrules.com>
Date: Thu, 18 Mar 2021 13:36:56 -0400
Subject: [PATCH] net/ark: refactor Rx buffer recovery

[ upstream commit 31d7dded033fc061950312253919237dde07ac63 ]

Allocate mbufs for Rx path in bulk of at least 64 buffers
to improve performance. Allow recovery even without
a Rx operation to support lack of buffers in pool.

Fixes: be410a861598 ("net/ark: add recovery for lack of mbufs")

Signed-off-by: Ed Czeck <ed.czeck at atomicrules.com>
---
 drivers/net/ark/ark_ethdev_rx.c | 49 ++++++++-------------------------
 1 file changed, 11 insertions(+), 38 deletions(-)

diff --git a/drivers/net/ark/ark_ethdev_rx.c b/drivers/net/ark/ark_ethdev_rx.c
index 6156730bb2..32ee5c1264 100644
--- a/drivers/net/ark/ark_ethdev_rx.c
+++ b/drivers/net/ark/ark_ethdev_rx.c
@@ -25,9 +25,6 @@ static uint32_t eth_ark_rx_jumbo(struct ark_rx_queue *queue,
 				 struct rte_mbuf *mbuf0,
 				 uint32_t cons_index);
 static inline int eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue);
-static int eth_ark_rx_seed_recovery(struct ark_rx_queue *queue,
-				    uint32_t *pnb,
-				    struct rte_mbuf **mbufs);
 
 /* ************************************************************************* */
 struct ark_rx_queue {
@@ -53,7 +50,7 @@ struct ark_rx_queue {
 	/* The queue Index is used within the dpdk device structures */
 	uint16_t queue_index;
 
-	uint32_t last_cons;
+	uint32_t unused;
 
 	/* separate cache line */
 	/* second cache line - fields only used in slow path */
@@ -104,9 +101,8 @@ static inline void
 eth_ark_rx_update_cons_index(struct ark_rx_queue *queue, uint32_t cons_index)
 {
 	queue->cons_index = cons_index;
-	eth_ark_rx_seed_mbufs(queue);
-	if (((cons_index - queue->last_cons) >= 64U)) {
-		queue->last_cons = cons_index;
+	if ((cons_index + queue->queue_size - queue->seed_index) >= 64U) {
+		eth_ark_rx_seed_mbufs(queue);
 		ark_mpu_set_producer(queue->mpu, queue->seed_index);
 	}
 }
@@ -317,9 +313,7 @@ eth_ark_recv_pkts(void *rx_queue,
 			break;
 	}
 
-	if (unlikely(nb != 0))
-		/* report next free to FPGA */
-		eth_ark_rx_update_cons_index(queue, cons_index);
+	eth_ark_rx_update_cons_index(queue, cons_index);
 
 	return nb;
 }
@@ -456,11 +450,13 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
 	int status = rte_pktmbuf_alloc_bulk(queue->mb_pool, mbufs, nb);
 
 	if (unlikely(status != 0)) {
-		/* Try to recover from lack of mbufs in pool */
-		status = eth_ark_rx_seed_recovery(queue, &nb, mbufs);
-		if (unlikely(status != 0)) {
-			return -1;
-		}
+		ARK_PMD_LOG(NOTICE,
+			    "Could not allocate %u mbufs from pool"
+			    " for RX queue %u;"
+			    " %u free buffers remaining in queue\n",
+			    nb, queue->queue_index,
+			    queue->seed_index - queue->cons_index);
+		return -1;
 	}
 
 	if (ARK_RX_DEBUG) {		/* DEBUG */
@@ -509,29 +505,6 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
 	return 0;
 }
 
-int
-eth_ark_rx_seed_recovery(struct ark_rx_queue *queue,
-			 uint32_t *pnb,
-			 struct rte_mbuf **mbufs)
-{
-	int status = -1;
-
-	/* Ignore small allocation failures */
-	if (*pnb <= 64)
-		return -1;
-
-	*pnb = 64U;
-	status = rte_pktmbuf_alloc_bulk(queue->mb_pool, mbufs, *pnb);
-	if (status != 0) {
-		PMD_DRV_LOG(ERR,
-			    "ARK: Could not allocate %u mbufs from pool for RX queue %u;"
-			    " %u free buffers remaining in queue\n",
-			    *pnb, queue->queue_index,
-			    queue->seed_index - queue->cons_index);
-	}
-	return status;
-}
-
 void
 eth_ark_rx_dump_queue(struct rte_eth_dev *dev, uint16_t queue_id,
 		      const char *msg)
-- 
2.31.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-05-17 17:40:31.514966347 +0200
+++ 0050-net-ark-refactor-Rx-buffer-recovery.patch	2021-05-17 17:40:29.183809571 +0200
@@ -1 +1 @@
-From 31d7dded033fc061950312253919237dde07ac63 Mon Sep 17 00:00:00 2001
+From 099ab9bb98acf79008db7fcb86b8dad2664e2a56 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 31d7dded033fc061950312253919237dde07ac63 ]
+
@@ -11 +12,0 @@
-Cc: stable at dpdk.org
@@ -19 +20 @@
-index d29d3db783..8e55b851a2 100644
+index 6156730bb2..32ee5c1264 100644
@@ -22 +23 @@
-@@ -26,9 +26,6 @@ static uint32_t eth_ark_rx_jumbo(struct ark_rx_queue *queue,
+@@ -25,9 +25,6 @@ static uint32_t eth_ark_rx_jumbo(struct ark_rx_queue *queue,
@@ -32 +33 @@
-@@ -54,7 +51,7 @@ struct ark_rx_queue {
+@@ -53,7 +50,7 @@ struct ark_rx_queue {
@@ -41 +42 @@
-@@ -105,9 +102,8 @@ static inline void
+@@ -104,9 +101,8 @@ static inline void
@@ -53 +54 @@
-@@ -321,9 +317,7 @@ eth_ark_recv_pkts(void *rx_queue,
+@@ -317,9 +313,7 @@ eth_ark_recv_pkts(void *rx_queue,
@@ -64 +65 @@
-@@ -458,11 +452,13 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
+@@ -456,11 +450,13 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
@@ -82,2 +83,2 @@
- 	if (ARK_DEBUG_CORE) {		/* DEBUG */
-@@ -511,29 +507,6 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
+ 	if (ARK_RX_DEBUG) {		/* DEBUG */
+@@ -509,29 +505,6 @@ eth_ark_rx_seed_mbufs(struct ark_rx_queue *queue)
@@ -101 +102 @@
--		ARK_PMD_LOG(NOTICE,
+-		PMD_DRV_LOG(ERR,