VNIC testing on multi-core Power systems showed SAR stats drift and packet rate inconsistencies under load. Implements ndo_get_stats64 to provide safe aggregation of queue-level atomic64 counters into rtnl_link_stats64 for use by tools like 'ip -s', 'ifconfig', and 'sar'. Switch to ndo_get_stats64 to align SAR reporting with the standard kernel interface for retrieving netdev stats. This removes redundant per-adapter stat updates, reduces overhead, eliminates cacheline bouncing from hot path updates, and improves the accuracy of reported packet rates. Signed-off-by: Mingming Cao Reviewed-by: Brian King Reviewed-by: Dave Marquardt Reviewed-by: Simon Horman ---- Changes since v3: link to v3: https://www.spinics.net/lists/netdev/msg1107999.html -- keep per queue counters as u64 (this patch) and drop off patch 1 in v3 --- drivers/net/ethernet/ibm/ibmvnic.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 92647e137cf8..eec971567aac 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -2312,8 +2312,6 @@ static void ibmvnic_tx_scrq_clean_buffer(struct ibmvnic_adapter *adapter, tx_pool->num_buffers - 1 : tx_pool->consumer_index - 1; tx_buff = &tx_pool->tx_buff[index]; - adapter->netdev->stats.tx_packets--; - adapter->netdev->stats.tx_bytes -= tx_buff->skb->len; adapter->tx_stats_buffers[queue_num].batched_packets--; adapter->tx_stats_buffers[queue_num].bytes -= tx_buff->skb->len; @@ -2647,9 +2645,6 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) } out: rcu_read_unlock(); - netdev->stats.tx_dropped += tx_dropped; - netdev->stats.tx_bytes += tx_bytes; - netdev->stats.tx_packets += tx_bpackets + tx_dpackets; adapter->tx_send_failed += tx_send_failed; adapter->tx_map_failed += tx_map_failed; adapter->tx_stats_buffers[queue_num].batched_packets += tx_bpackets; @@ -3452,6 +3447,25 @@ static int ibmvnic_reset(struct ibmvnic_adapter *adapter, return -ret; } +static void ibmvnic_get_stats64(struct net_device *netdev, + struct rtnl_link_stats64 *stats) +{ + struct ibmvnic_adapter *adapter = netdev_priv(netdev); + int i; + + for (i = 0; i < adapter->req_rx_queues; i++) { + stats->rx_packets += adapter->rx_stats_buffers[i].packets; + stats->rx_bytes += adapter->rx_stats_buffers[i].bytes; + } + + for (i = 0; i < adapter->req_tx_queues; i++) { + stats->tx_packets += adapter->tx_stats_buffers[i].batched_packets; + stats->tx_packets += adapter->tx_stats_buffers[i].direct_packets; + stats->tx_bytes += adapter->tx_stats_buffers[i].bytes; + stats->tx_dropped += adapter->tx_stats_buffers[i].dropped_packets; + } +} + static void ibmvnic_tx_timeout(struct net_device *dev, unsigned int txqueue) { struct ibmvnic_adapter *adapter = netdev_priv(dev); @@ -3567,8 +3581,6 @@ static int ibmvnic_poll(struct napi_struct *napi, int budget) length = skb->len; napi_gro_receive(napi, skb); /* send it up */ - netdev->stats.rx_packets++; - netdev->stats.rx_bytes += length; adapter->rx_stats_buffers[scrq_num].packets++; adapter->rx_stats_buffers[scrq_num].bytes += length; frames_processed++; @@ -3678,6 +3690,7 @@ static const struct net_device_ops ibmvnic_netdev_ops = { .ndo_set_rx_mode = ibmvnic_set_multi, .ndo_set_mac_address = ibmvnic_set_mac, .ndo_validate_addr = eth_validate_addr, + .ndo_get_stats64 = ibmvnic_get_stats64, .ndo_tx_timeout = ibmvnic_tx_timeout, .ndo_change_mtu = ibmvnic_change_mtu, .ndo_features_check = ibmvnic_features_check, -- 2.39.3 (Apple Git-146)