[dpdk-stable] patch 'app/testpmd: fix statistics after reset' has been queued to LTS release 18.11.9

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.9

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 06/10/20. 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/kevintraynor/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable-queue/commit/9478a1a301d359e05f271cd5295cf392fa124517

Thanks.

Kevin.

---
>From 9478a1a301d359e05f271cd5295cf392fa124517 Mon Sep 17 00:00:00 2001
From: "Wei Hu (Xavier)" <xavier.huwei at huawei.com>
Date: Tue, 28 Apr 2020 19:50:45 +0800
Subject: [PATCH] app/testpmd: fix statistics after reset

[ upstream commit 9eb974221f44cf210fe5d883bdccfcb48de75fc6 ]

Currently, when running start/clear stats&xstats/stop command many times
based on testpmd application, there are incorrect forward Rx/Tx-packets
stats as below:
---------------------- Forward statistics for port 0  --------------
RX-packets: 18446744073709544808 RX-dropped: 0                <snip>
TX-packets: 18446744073709536616 TX-dropped: 0                <snip>
--------------------------------------------------------------------

The root cause as below:
1. The struct rte_port of testpmd.h has a member variable "struct
   rte_eth_stats stats" to store the last port statistics.
2. When running start command, it execute cmd_start_parsed ->
   start_packet_forwarding -> fwd_stats_reset, which call
   rte_eth_stats_get API function to save current port statistics.
3. When running stop command, it execute fwd_stats_display, which call
   rte_eth_stats_get to get current port statistics, and then minus last
   port statistics.
4. If we run clear stats or xstats after start command, then run stop,
   it may display above incorrect stats because the current
   Rx/Tx-packets is lower than the last saved RX/TX-packets(uint64_t
   overflow).

This patch fixes it by clearing last port statistics when executing
"clear stats/xstats" command.

Fixes: af75078fece3 ("first public release")

Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
Signed-off-by: Wei Hu (Xavier) <xavier.huwei at huawei.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit at intel.com>
---
 app/test-pmd/config.c                       | 26 ++++++++++++++++++++-
 doc/guides/testpmd_app_ug/testpmd_funcs.rst |  2 +-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
index 6e9a2042c2..0e5d77159d 100644
--- a/app/test-pmd/config.c
+++ b/app/test-pmd/config.c
@@ -205,9 +205,24 @@ void
 nic_stats_clear(portid_t port_id)
 {
+	int ret;
+
 	if (port_id_is_invalid(port_id, ENABLED_WARN)) {
 		print_valid_ports();
 		return;
 	}
-	rte_eth_stats_reset(port_id);
+
+	ret = rte_eth_stats_reset(port_id);
+	if (ret != 0) {
+		printf("%s: Error: failed to reset stats (port %u): %s",
+		       __func__, port_id, strerror(ret));
+		return;
+	}
+
+	ret = rte_eth_stats_get(port_id, &ports[port_id].stats);
+	if (ret != 0) {
+		printf("%s: Error: failed to get stats (port %u): %s",
+		       __func__, port_id, strerror(ret));
+		return;
+	}
 	printf("\n  NIC statistics for port %d cleared\n", port_id);
 }
@@ -279,4 +294,6 @@ void
 nic_xstats_clear(portid_t port_id)
 {
+	int ret;
+
 	if (port_id_is_invalid(port_id, ENABLED_WARN)) {
 		print_valid_ports();
@@ -284,4 +301,11 @@ nic_xstats_clear(portid_t port_id)
 	}
 	rte_eth_xstats_reset(port_id);
+
+	ret = rte_eth_stats_get(port_id, &ports[port_id].stats);
+	if (ret != 0) {
+		printf("%s: Error: failed to get stats (port %u): %s",
+		       __func__, port_id, strerror(ret));
+		return;
+	}
 }
 
diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
index c327d1f4df..0d71e20c64 100644
--- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
+++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
@@ -239,5 +239,5 @@ clear port
 ~~~~~~~~~~
 
-Clear the port statistics for a given port or for all ports::
+Clear the port statistics and forward engine statistics for a given port or for all ports::
 
    testpmd> clear port (info|stats|xstats|fdir|stat_qmap) (port_id|all)
-- 
2.21.3

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-06-05 19:20:52.664416455 +0100
+++ 0033-app-testpmd-fix-statistics-after-reset.patch	2020-06-05 19:20:50.771041699 +0100
@@ -1 +1 @@
-From 9eb974221f44cf210fe5d883bdccfcb48de75fc6 Mon Sep 17 00:00:00 2001
+From 9478a1a301d359e05f271cd5295cf392fa124517 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 9eb974221f44cf210fe5d883bdccfcb48de75fc6 ]
+
@@ -32 +33,0 @@
-Cc: stable at dpdk.org
@@ -43 +44 @@
-index 035d336ab5..5381207cc2 100644
+index 6e9a2042c2..0e5d77159d 100644
@@ -46 +47 @@
-@@ -235,9 +235,24 @@ void
+@@ -205,9 +205,24 @@ void
@@ -72,3 +73,4 @@
-@@ -315,8 +330,17 @@ nic_xstats_clear(portid_t port_id)
- 		return;
- 	}
+@@ -279,4 +294,6 @@ void
+ nic_xstats_clear(portid_t port_id)
+ {
++	int ret;
@@ -76,6 +78,5 @@
- 	ret = rte_eth_xstats_reset(port_id);
- 	if (ret != 0) {
- 		printf("%s: Error: failed to reset xstats (port %u): %s",
- 		       __func__, port_id, strerror(ret));
-+		return;
-+	}
+ 	if (port_id_is_invalid(port_id, ENABLED_WARN)) {
+ 		print_valid_ports();
+@@ -284,4 +301,11 @@ nic_xstats_clear(portid_t port_id)
+ 	}
+ 	rte_eth_xstats_reset(port_id);
@@ -88 +89 @@
- 	}
++	}
@@ -89,0 +91 @@
+ 
@@ -91 +93 @@
-index 19260cc2d9..581cd45ebb 100644
+index c327d1f4df..0d71e20c64 100644
@@ -94 +96 @@
-@@ -238,5 +238,5 @@ clear port
+@@ -239,5 +239,5 @@ clear port