[dpdk-dev] [PATCH] ether: fix incorrect stats query for lowest xstat id

[dpdk-dev] [PATCH] ether: fix incorrect stats query for lowest xstat id

[Bruce Richardson]

When querying either the name or the value of a stat using the xstats
APIs, a check is done to see if the regular stats API or the xstats APIs
for the driver need to be used. However, the id of the stat requested is
checked to see if it is greater than the number of basic stats, rather
than checking for greater-or-equal, meaning that the xstat with the lowest
id gets incorrectly treated as a basic stat.

This problem manifests itself when you call proc_info using "--xstats-id"
for the first xstat, you get no name of the stat printed, and a random(ish)
stat value.

Fixes: 4773152f850b ("ethdev: optimize xstats by ids APIs")

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/librte_ether/rte_ethdev.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 78bed1a16..a6ce2a5ba 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -2045,7 +2045,7 @@ rte_eth_xstats_get_names_by_id(uint16_t port_id,
 
 	if (ids) {
 		for (i = 0; i < size; i++) {
-			if (ids[i] > basic_count) {
+			if (ids[i] >= basic_count) {
 				no_ext_stat_requested = 0;
 				break;
 			}
@@ -2225,7 +2225,7 @@ rte_eth_xstats_get_by_id(uint16_t port_id, const uint64_t *ids,
 
 	if (ids) {
 		for (i = 0; i < size; i++) {
-			if (ids[i] > basic_count) {
+			if (ids[i] >= basic_count) {
 				no_ext_stat_requested = 0;
 				break;
 			}
-- 
2.14.3

Re: [dpdk-dev] [PATCH] ether: fix incorrect stats query for lowest xstat id

[Ferruh Yigit]

On 2/6/2018 4:06 PM, Bruce Richardson wrote:
> When querying either the name or the value of a stat using the xstats
> APIs, a check is done to see if the regular stats API or the xstats APIs
> for the driver need to be used. However, the id of the stat requested is
> checked to see if it is greater than the number of basic stats, rather
> than checking for greater-or-equal, meaning that the xstat with the lowest
> id gets incorrectly treated as a basic stat.
> 
> This problem manifests itself when you call proc_info using "--xstats-id"
> for the first xstat, you get no name of the stat printed, and a random(ish)
> stat value.
> 
> Fixes: 4773152f850b ("ethdev: optimize xstats by ids APIs")
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

Re: [dpdk-dev] [PATCH] ether: fix incorrect stats query for lowest xstat id

[Thomas Monjalon]

06/02/2018 17:06, Bruce Richardson:
> When querying either the name or the value of a stat using the xstats
> APIs, a check is done to see if the regular stats API or the xstats APIs
> for the driver need to be used. However, the id of the stat requested is
> checked to see if it is greater than the number of basic stats, rather
> than checking for greater-or-equal, meaning that the xstat with the lowest
> id gets incorrectly treated as a basic stat.
> 
> This problem manifests itself when you call proc_info using "--xstats-id"
> for the first xstat, you get no name of the stat printed, and a random(ish)
> stat value.
> 
> Fixes: 4773152f850b ("ethdev: optimize xstats by ids APIs")
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Applied, thanks

It looks like the stats functions are the most reworked and fixed.
It is a no-end story. According to git statistics, it is probably
the most complicate code of DPDK :)
I am thinking about being more conservative and do not accept any
new change in these rocket science functions ;)