[dpdk-stable] patch 'app/testpmd: fix statistics after reset' has been queued to stable release 19.11.3

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 19.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 05/21/20. 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.

Thanks.

Luca Boccassi

---
>From 024a56857898bf3aabee0b15e9d44cb4d81776bf 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 62e547be09..42eba68b35 100644
--- a/app/test-pmd/config.c
+++ b/app/test-pmd/config.c
@@ -223,11 +223,26 @@ nic_stats_display(portid_t port_id)
 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);
 }
 
@@ -303,10 +318,19 @@ nic_xstats_clear(portid_t port_id)
 		print_valid_ports();
 		return;
 	}
+
 	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;
+	}
+
+	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 73ef0b41d3..78bdf60fe6 100644
--- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
+++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
@@ -237,7 +237,7 @@ Display the RSS hash functions and RSS hash key of a port::
 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)
 
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-05-19 14:04:51.957781396 +0100
+++ 0182-app-testpmd-fix-statistics-after-reset.patch	2020-05-19 14:04:44.532654101 +0100
@@ -1,8 +1,10 @@
-From 9eb974221f44cf210fe5d883bdccfcb48de75fc6 Mon Sep 17 00:00:00 2001
+From 024a56857898bf3aabee0b15e9d44cb4d81776bf 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:
@@ -29,7 +31,6 @@
 "clear stats/xstats" command.
 
 Fixes: af75078fece3 ("first public release")
-Cc: stable at dpdk.org
 
 Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
 Signed-off-by: Wei Hu (Xavier) <xavier.huwei at huawei.com>
@@ -40,10 +41,10 @@
  2 files changed, 26 insertions(+), 2 deletions(-)
 
 diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
-index 035d336ab5..5381207cc2 100644
+index 62e547be09..42eba68b35 100644
 --- a/app/test-pmd/config.c
 +++ b/app/test-pmd/config.c
-@@ -234,11 +234,26 @@ nic_stats_display(portid_t port_id)
+@@ -223,11 +223,26 @@ nic_stats_display(portid_t port_id)
  void
  nic_stats_clear(portid_t port_id)
  {
@@ -71,7 +72,7 @@
  	printf("\n  NIC statistics for port %d cleared\n", port_id);
  }
  
-@@ -314,10 +329,19 @@ nic_xstats_clear(portid_t port_id)
+@@ -303,10 +318,19 @@ nic_xstats_clear(portid_t port_id)
  		print_valid_ports();
  		return;
  	}
@@ -92,7 +93,7 @@
  }
  
 diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
-index 19260cc2d9..581cd45ebb 100644
+index 73ef0b41d3..78bdf60fe6 100644
 --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
 +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
 @@ -237,7 +237,7 @@ Display the RSS hash functions and RSS hash key of a port::