[RFC 2/5] net/ngbe: fix query handling in xstats_get

[Stephen Hemminger]

The xstats_get function in this driver did not act the same
as other drivers when queried. The correct check is to look
at the requested number of stats and compare it to the available
stats and if the request is too small, return the correct size.

Bugzilla ID: 1560
Fixes: 8b433d04adc9 ("net/ngbe: support device xstats")
Cc: jiawenwu at trustnetic.com

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/net/ngbe/ngbe_ethdev.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ngbe/ngbe_ethdev.c b/drivers/net/ngbe/ngbe_ethdev.c
index 6c45ffaad3..ee65829aa0 100644
--- a/drivers/net/ngbe/ngbe_ethdev.c
+++ b/drivers/net/ngbe/ngbe_ethdev.c
@@ -1693,19 +1693,16 @@ ngbe_dev_xstats_get(struct rte_eth_dev *dev, struct rte_eth_xstat *xstats,
 	struct ngbe_hw_stats *hw_stats = NGBE_DEV_STATS(dev);
 	unsigned int i, count;
 
-	ngbe_read_stats_registers(hw, hw_stats);
-
-	/* If this is a reset xstats is NULL, and we have cleared the
-	 * registers by reading them.
-	 */
 	count = ngbe_xstats_calc_num(dev);
-	if (xstats == NULL)
+	if (limit < count)
 		return count;
 
+	ngbe_read_stats_registers(hw, hw_stats);
+
 	limit = min(limit, ngbe_xstats_calc_num(dev));
 
 	/* Extended stats from ngbe_hw_stats */
-	for (i = 0; i < limit; i++) {
+	for (i = 0; i < count; i++) {
 		uint32_t offset = 0;
 
 		if (ngbe_get_offset_by_id(i, &offset)) {
-- 
2.45.2