This patch improves the ibmvnic driver by changing the per-queue packet and byte counters to atomic64_t types. This makes updates thread-safe and easier to manage across multiple cores. It also updates the ethtool statistics to safely read these new counters. Signed-off-by: Mingming Cao Reviewed-by: Brian King Reviewed-by: Dave Marquardt Reviewed by: Rick Lindsley Reviewed by: Haren Myneni --- drivers/net/ethernet/ibm/ibmvnic.c | 42 ++++++++++++++++++------------ drivers/net/ethernet/ibm/ibmvnic.h | 18 ++++++------- 2 files changed, 34 insertions(+), 26 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 92647e137cf8..79fdba4293a4 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -2314,9 +2314,17 @@ static void ibmvnic_tx_scrq_clean_buffer(struct ibmvnic_adapter *adapter, 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; + atomic64_dec(&adapter->tx_stats_buffers[queue_num].batched_packets); + if (atomic64_sub_return(tx_buff->skb->len, + &adapter->tx_stats_buffers[queue_num].bytes) < 0) { + atomic64_set(&adapter->tx_stats_buffers[queue_num].bytes, 0); + netdev_warn(adapter->netdev, + "TX stats underflow on queue %u: bytes (%lld) < skb->len (%u),\n" + "clamping to 0\n", + queue_num, + atomic64_read(&adapter->tx_stats_buffers[queue_num].bytes), + tx_buff->skb->len); + } dev_kfree_skb_any(tx_buff->skb); tx_buff->skb = NULL; adapter->netdev->stats.tx_dropped++; @@ -2652,10 +2660,10 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) 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; - adapter->tx_stats_buffers[queue_num].direct_packets += tx_dpackets; - adapter->tx_stats_buffers[queue_num].bytes += tx_bytes; - adapter->tx_stats_buffers[queue_num].dropped_packets += tx_dropped; + atomic64_add(tx_bpackets, &adapter->tx_stats_buffers[queue_num].batched_packets); + atomic64_add(tx_dpackets, &adapter->tx_stats_buffers[queue_num].direct_packets); + atomic64_add(tx_bytes, &adapter->tx_stats_buffers[queue_num].bytes); + atomic64_add(tx_dropped, &adapter->tx_stats_buffers[queue_num].dropped_packets); return ret; } @@ -3569,8 +3577,8 @@ static int ibmvnic_poll(struct napi_struct *napi, int budget) 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; + atomic64_inc(&adapter->rx_stats_buffers[scrq_num].packets); + atomic64_add(length, &adapter->rx_stats_buffers[scrq_num].bytes); frames_processed++; } @@ -3874,22 +3882,22 @@ static void ibmvnic_get_ethtool_stats(struct net_device *dev, (adapter, ibmvnic_stats[i].offset)); for (j = 0; j < adapter->req_tx_queues; j++) { - data[i] = adapter->tx_stats_buffers[j].batched_packets; + data[i] = atomic64_read(&adapter->tx_stats_buffers[j].batched_packets); i++; - data[i] = adapter->tx_stats_buffers[j].direct_packets; + data[i] = atomic64_read(&adapter->tx_stats_buffers[j].direct_packets); i++; - data[i] = adapter->tx_stats_buffers[j].bytes; + data[i] = atomic64_read(&adapter->tx_stats_buffers[j].bytes); i++; - data[i] = adapter->tx_stats_buffers[j].dropped_packets; + data[i] = atomic64_read(&adapter->tx_stats_buffers[j].dropped_packets); i++; } for (j = 0; j < adapter->req_rx_queues; j++) { - data[i] = adapter->rx_stats_buffers[j].packets; + data[i] = atomic64_read(&adapter->rx_stats_buffers[j].packets); i++; - data[i] = adapter->rx_stats_buffers[j].bytes; + data[i] = atomic64_read(&adapter->rx_stats_buffers[j].bytes); i++; - data[i] = adapter->rx_stats_buffers[j].interrupts; + data[i] = atomic64_read(&adapter->rx_stats_buffers[j].interrupts); i++; } } @@ -4307,7 +4315,7 @@ static irqreturn_t ibmvnic_interrupt_rx(int irq, void *instance) if (unlikely(adapter->state != VNIC_OPEN)) return IRQ_NONE; - adapter->rx_stats_buffers[scrq->scrq_num].interrupts++; + atomic64_inc(&adapter->rx_stats_buffers[scrq->scrq_num].interrupts); if (napi_schedule_prep(&adapter->napi[scrq->scrq_num])) { disable_scrq_irq(adapter, scrq); diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h index 246ddce753f9..e574eed97cc0 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.h +++ b/drivers/net/ethernet/ibm/ibmvnic.h @@ -212,23 +212,23 @@ struct ibmvnic_statistics { } __packed __aligned(8); struct ibmvnic_tx_queue_stats { - u64 batched_packets; - u64 direct_packets; - u64 bytes; - u64 dropped_packets; + atomic64_t batched_packets; + atomic64_t direct_packets; + atomic64_t bytes; + atomic64_t dropped_packets; }; #define NUM_TX_STATS \ - (sizeof(struct ibmvnic_tx_queue_stats) / sizeof(u64)) + (sizeof(struct ibmvnic_tx_queue_stats) / sizeof(atomic64_t)) struct ibmvnic_rx_queue_stats { - u64 packets; - u64 bytes; - u64 interrupts; + atomic64_t packets; + atomic64_t bytes; + atomic64_t interrupts; }; #define NUM_RX_STATS \ - (sizeof(struct ibmvnic_rx_queue_stats) / sizeof(u64)) + (sizeof(struct ibmvnic_rx_queue_stats) / sizeof(atomic64_t)) struct ibmvnic_acl_buffer { __be32 len; -- 2.39.3 (Apple Git-146) 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 --- drivers/net/ethernet/ibm/ibmvnic.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 79fdba4293a4..6dd7809b1bc7 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; atomic64_dec(&adapter->tx_stats_buffers[queue_num].batched_packets); if (atomic64_sub_return(tx_buff->skb->len, &adapter->tx_stats_buffers[queue_num].bytes) < 0) { @@ -2325,9 +2323,9 @@ static void ibmvnic_tx_scrq_clean_buffer(struct ibmvnic_adapter *adapter, atomic64_read(&adapter->tx_stats_buffers[queue_num].bytes), tx_buff->skb->len); } + atomic64_inc(&adapter->tx_stats_buffers[queue_num].dropped_packets); dev_kfree_skb_any(tx_buff->skb); tx_buff->skb = NULL; - adapter->netdev->stats.tx_dropped++; } ind_bufp->index = 0; @@ -2655,9 +2653,6 @@ 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; atomic64_add(tx_bpackets, &adapter->tx_stats_buffers[queue_num].batched_packets); @@ -3460,6 +3455,25 @@ 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 += atomic64_read(&adapter->rx_stats_buffers[i].packets); + stats->rx_bytes += atomic64_read(&adapter->rx_stats_buffers[i].bytes); + } + + for (i = 0; i < adapter->req_tx_queues; i++) { + stats->tx_packets += atomic64_read(&adapter->tx_stats_buffers[i].batched_packets); + stats->tx_packets += atomic64_read(&adapter->tx_stats_buffers[i].direct_packets); + stats->tx_bytes += atomic64_read(&adapter->tx_stats_buffers[i].bytes); + stats->tx_dropped += atomic64_read(&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); @@ -3575,8 +3589,6 @@ 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; atomic64_inc(&adapter->rx_stats_buffers[scrq_num].packets); atomic64_add(length, &adapter->rx_stats_buffers[scrq_num].bytes); frames_processed++; @@ -3686,6 +3698,7 @@ 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)