metrics: do not fail silently when uninitialised

If rte_metrics_init() had not been called and hence the internal
metric storage is not allocated, rte_metrics_get_values() and
rte_metrics_get_name() would silently fail by returning zero
(i.e. no metrics registered). This patch changes the result of
this scenario to an explicit fail by returning -EIO.

Fixes: 349950ddb9c5 ("metrics: add information metrics library")
Cc: stable@dpdk.org
Signed-off-by: Remy Horton <remy.horton@intel.com>

diff --git a/lib/librte_metrics/rte_metrics.c b/lib/librte_metrics/rte_metrics.c
index b5638f5..038f58b 100644 (file)
--- a/lib/librte_metrics/rte_metrics.c
+++ b/lib/librte_metrics/rte_metrics.c
@@ -205,9 +205,8 @@ rte_metrics_get_names(struct rte_metric_name *names,
        int return_value;
 
        memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
-       /* If not allocated, fail silently */
        if (memzone == NULL)
-               return 0;
+               return -EIO;
 
        stats = memzone->addr;
        rte_spinlock_lock(&stats->lock);
@@ -243,9 +242,9 @@ rte_metrics_get_values(int port_id,
                return -EINVAL;
 
        memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
-       /* If not allocated, fail silently */
        if (memzone == NULL)
-               return 0;
+               return -EIO;
+
        stats = memzone->addr;
        rte_spinlock_lock(&stats->lock);