[PATCH 5.8 10/16] net: ena: Make missed_tx stat incremental

From: Greg Kroah-Hartman
Date: Wed Aug 26 2020 - 08:04:44 EST


From: Shay Agroskin <shayagr@xxxxxxxxxx>

[ Upstream commit ccd143e5150f24b9ba15145c7221b61dd9e41021 ]

Most statistics in ena driver are incremented, meaning that a stat's
value is a sum of all increases done to it since driver/queue
initialization.

This patch makes all statistics this way, effectively making missed_tx
statistic incremental.
Also added a comment regarding rx_drops and tx_drops to make it
clearer how these counters are calculated.

Fixes: 11095fdb712b ("net: ena: add statistics for missed tx packets")
Signed-off-by: Shay Agroskin <shayagr@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/amazon/ena/ena_netdev.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -3609,7 +3609,7 @@ static int check_missing_comp_in_tx_queu
}

u64_stats_update_begin(&tx_ring->syncp);
- tx_ring->tx_stats.missed_tx = missed_tx;
+ tx_ring->tx_stats.missed_tx += missed_tx;
u64_stats_update_end(&tx_ring->syncp);

return rc;
@@ -4537,6 +4537,9 @@ static void ena_keep_alive_wd(void *adap
tx_drops = ((u64)desc->tx_drops_high << 32) | desc->tx_drops_low;

u64_stats_update_begin(&adapter->syncp);
+ /* These stats are accumulated by the device, so the counters indicate
+ * all drops since last reset.
+ */
adapter->dev_stats.rx_drops = rx_drops;
adapter->dev_stats.tx_drops = tx_drops;
u64_stats_update_end(&adapter->syncp);