patch 'net/axgbe: fix xstats get return if xstats is null' has been queued to stable release 20.11.6

[Xueming Li]

Hi,

FYI, your patch has been queued to stable release 20.11.6

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 06/23/22. 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/steevenlee/dpdk

This queued commit can be viewed at:
https://github.com/steevenlee/dpdk/commit/7d17ff9a817b0cc250ee5c18f7579a09454f8e04

Thanks.

Xueming Li <xuemingl at nvidia.com>

---
>From 7d17ff9a817b0cc250ee5c18f7579a09454f8e04 Mon Sep 17 00:00:00 2001
From: Chengwen Feng <fengchengwen at huawei.com>
Date: Fri, 13 May 2022 10:53:54 +0800
Subject: [PATCH] net/axgbe: fix xstats get return if xstats is null
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: Xueming Li <xuemingl at nvidia.com>

[ upstream commit 93041fd5149a4f8cc795ea8ebb229415e2994e51 ]

Many user (e.g. telemetry) invokes rte_eth_xstats_get(port_id, NULL, 0)
to retrieve the required number of elements, but currently axgbe PMD
returns zero when xstats is null.

Remove the logic of "return zero when xstats is NULL", and add the logic
of "return the required number of entries when n is lower than the
required number of entries".

Fixes: 9d1ef6b2e731 ("net/axgbe: add xstats")

Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
Acked-by: Morten Brørup <mb at smartsharesystems.com>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
---
 drivers/net/axgbe/axgbe_ethdev.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/axgbe/axgbe_ethdev.c b/drivers/net/axgbe/axgbe_ethdev.c
index 6e63d7673b..586cf6974c 100644
--- a/drivers/net/axgbe/axgbe_ethdev.c
+++ b/drivers/net/axgbe/axgbe_ethdev.c
@@ -984,18 +984,18 @@ axgbe_dev_xstats_get(struct rte_eth_dev *dev, struct rte_eth_xstat *stats,
 	struct axgbe_port *pdata = dev->data->dev_private;
 	unsigned int i;
 
-	if (!stats)
-		return 0;
+	if (n < AXGBE_XSTATS_COUNT)
+		return AXGBE_XSTATS_COUNT;
 
 	axgbe_read_mmc_stats(pdata);
 
-	for (i = 0; i < n && i < AXGBE_XSTATS_COUNT; i++) {
+	for (i = 0; i < AXGBE_XSTATS_COUNT; i++) {
 		stats[i].id = i;
 		stats[i].value = *(u64 *)((uint8_t *)&pdata->mmc_stats +
 				axgbe_xstats_strings[i].offset);
 	}
 
-	return i;
+	return AXGBE_XSTATS_COUNT;
 }
 
 static int
-- 
2.35.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2022-06-21 15:37:52.627923176 +0800
+++ 0074-net-axgbe-fix-xstats-get-return-if-xstats-is-null.patch	2022-06-21 15:37:49.111118179 +0800
@@ -1 +1 @@
-From 93041fd5149a4f8cc795ea8ebb229415e2994e51 Mon Sep 17 00:00:00 2001
+From 7d17ff9a817b0cc250ee5c18f7579a09454f8e04 Mon Sep 17 00:00:00 2001
@@ -7,0 +8,3 @@
+Cc: Xueming Li <xuemingl at nvidia.com>
+
+[ upstream commit 93041fd5149a4f8cc795ea8ebb229415e2994e51 ]
@@ -18 +20,0 @@
-Cc: stable at dpdk.org
@@ -28 +30 @@
-index 951da5cc26..e6822fa711 100644
+index 6e63d7673b..586cf6974c 100644
@@ -31 +33 @@
-@@ -1013,18 +1013,18 @@ axgbe_dev_xstats_get(struct rte_eth_dev *dev, struct rte_eth_xstat *stats,
+@@ -984,18 +984,18 @@ axgbe_dev_xstats_get(struct rte_eth_dev *dev, struct rte_eth_xstat *stats,