From fa59dc2f6fc616fde3941f62ccd4adcaa21ccd47 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Fri, 7 Jun 2024 18:25:24 +0800 Subject: [PATCH 1/3] net: core,vrf: Change pcpu_dstat fields to u64_stats_t The pcpu_sw_netstats and pcpu_lstats structs both contain a set of u64_stats_t fields for individual stats, but pcpu_dstats uses u64s instead. Make this consistent by using u64_stats_t across all stats types. The per-cpu dstats are only used by the vrf driver at present, so update that driver as part of this change. Signed-off-by: Jeremy Kerr Reviewed-by: Simon Horman Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20240607-dstats-v3-1-cc781fe116f7@codeconstruct.com.au Signed-off-by: Jakub Kicinski --- drivers/net/vrf.c | 38 ++++++++++++++++++++++---------------- include/linux/netdevice.h | 12 ++++++------ 2 files changed, 28 insertions(+), 22 deletions(-) diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index 3a252ac5dd28..5018831b2a79 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -126,8 +126,8 @@ static void vrf_rx_stats(struct net_device *dev, int len) struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats); u64_stats_update_begin(&dstats->syncp); - dstats->rx_packets++; - dstats->rx_bytes += len; + u64_stats_inc(&dstats->rx_packets); + u64_stats_add(&dstats->rx_bytes, len); u64_stats_update_end(&dstats->syncp); } @@ -150,11 +150,11 @@ static void vrf_get_stats64(struct net_device *dev, dstats = per_cpu_ptr(dev->dstats, i); do { start = u64_stats_fetch_begin(&dstats->syncp); - tbytes = dstats->tx_bytes; - tpkts = dstats->tx_packets; - tdrops = dstats->tx_drops; - rbytes = dstats->rx_bytes; - rpkts = dstats->rx_packets; + tbytes = u64_stats_read(&dstats->tx_bytes); + tpkts = u64_stats_read(&dstats->tx_packets); + tdrops = u64_stats_read(&dstats->tx_drops); + rbytes = u64_stats_read(&dstats->rx_bytes); + rpkts = u64_stats_read(&dstats->rx_packets); } while (u64_stats_fetch_retry(&dstats->syncp, start)); stats->tx_bytes += tbytes; stats->tx_packets += tpkts; @@ -408,10 +408,15 @@ static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev, skb->protocol = eth_type_trans(skb, dev); - if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) + if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) { vrf_rx_stats(dev, len); - else - this_cpu_inc(dev->dstats->rx_drops); + } else { + struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats); + + u64_stats_update_begin(&dstats->syncp); + u64_stats_inc(&dstats->rx_drops); + u64_stats_update_end(&dstats->syncp); + } return NETDEV_TX_OK; } @@ -599,19 +604,20 @@ static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev) static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev) { + struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats); + int len = skb->len; netdev_tx_t ret = is_ip_tx_frame(skb, dev); + u64_stats_update_begin(&dstats->syncp); if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) { - struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats); - u64_stats_update_begin(&dstats->syncp); - dstats->tx_packets++; - dstats->tx_bytes += len; - u64_stats_update_end(&dstats->syncp); + u64_stats_inc(&dstats->tx_packets); + u64_stats_add(&dstats->tx_bytes, len); } else { - this_cpu_inc(dev->dstats->tx_drops); + u64_stats_inc(&dstats->tx_drops); } + u64_stats_update_end(&dstats->syncp); return ret; } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d20c6c99eb88..f148a01dd1d1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2731,12 +2731,12 @@ struct pcpu_sw_netstats { } __aligned(4 * sizeof(u64)); struct pcpu_dstats { - u64 rx_packets; - u64 rx_bytes; - u64 rx_drops; - u64 tx_packets; - u64 tx_bytes; - u64 tx_drops; + u64_stats_t rx_packets; + u64_stats_t rx_bytes; + u64_stats_t rx_drops; + u64_stats_t tx_packets; + u64_stats_t tx_bytes; + u64_stats_t tx_drops; struct u64_stats_sync syncp; } __aligned(8 * sizeof(u64)); From 94b601bc4f8528262b2b83194b7fd3fc2a6da75a Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Fri, 7 Jun 2024 18:25:25 +0800 Subject: [PATCH 2/3] net: core: Implement dstats-type stats collections We currently have dev_get_tstats64() for collecting per-cpu stats of type pcpu_sw_netstats ("tstats"). However, tstats doesn't allow for accounting tx/rx drops. We do have a stats variant that does have stats for dropped packets: struct pcpu_dstats, but there are no core helpers for using those stats. The VRF driver uses dstats, by providing its own collation/fetch functions to do so. This change adds a common implementation for dstats-type collection, used when pcpu_stat_type == NETDEV_PCPU_STAT_DSTAT. This is based on the VRF driver's existing stats collator (plus the unused tx_drops stat from there). We will switch the VRF driver to use this in the next change. Signed-off-by: Jeremy Kerr Reviewed-by: Simon Horman Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20240607-dstats-v3-2-cc781fe116f7@codeconstruct.com.au Signed-off-by: Jakub Kicinski --- net/core/dev.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/net/core/dev.c b/net/core/dev.c index e62698c7a0e6..c361a7b69da8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10703,6 +10703,54 @@ void netdev_run_todo(void) wake_up(&netdev_unregistering_wq); } +/* Collate per-cpu network dstats statistics + * + * Read per-cpu network statistics from dev->dstats and populate the related + * fields in @s. + */ +static void dev_fetch_dstats(struct rtnl_link_stats64 *s, + const struct pcpu_dstats __percpu *dstats) +{ + int cpu; + + for_each_possible_cpu(cpu) { + u64 rx_packets, rx_bytes, rx_drops; + u64 tx_packets, tx_bytes, tx_drops; + const struct pcpu_dstats *stats; + unsigned int start; + + stats = per_cpu_ptr(dstats, cpu); + do { + start = u64_stats_fetch_begin(&stats->syncp); + rx_packets = u64_stats_read(&stats->rx_packets); + rx_bytes = u64_stats_read(&stats->rx_bytes); + rx_drops = u64_stats_read(&stats->rx_drops); + tx_packets = u64_stats_read(&stats->tx_packets); + tx_bytes = u64_stats_read(&stats->tx_bytes); + tx_drops = u64_stats_read(&stats->tx_drops); + } while (u64_stats_fetch_retry(&stats->syncp, start)); + + s->rx_packets += rx_packets; + s->rx_bytes += rx_bytes; + s->rx_dropped += rx_drops; + s->tx_packets += tx_packets; + s->tx_bytes += tx_bytes; + s->tx_dropped += tx_drops; + } +} + +/* ndo_get_stats64 implementation for dtstats-based accounting. + * + * Populate @s from dev->stats and dev->dstats. This is used internally by the + * core for NETDEV_PCPU_STAT_DSTAT-type stats collection. + */ +static void dev_get_dstats64(const struct net_device *dev, + struct rtnl_link_stats64 *s) +{ + netdev_stats_to_stats64(s, &dev->stats); + dev_fetch_dstats(s, dev->dstats); +} + /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has * all the same fields in the same order as net_device_stats, with only * the type differing, but rtnl_link_stats64 may have additional fields @@ -10779,6 +10827,8 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) { dev_get_tstats64(dev, storage); + } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) { + dev_get_dstats64(dev, storage); } else { netdev_stats_to_stats64(storage, &dev->stats); } From 2202576d4631b977a95162a387c0c9fb4ca6819c Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Fri, 7 Jun 2024 18:25:26 +0800 Subject: [PATCH 3/3] net: vrf: move to generic dstat helpers The vrf driver has its own dstats-to-rtnl_link_stats64 collection, but we now have a generic implementation for dstats collection, so switch to this. In doing so, we fix a minor issue where the (non-percpu) dev->stats->tx_errors value was never collected into rtnl_link_stats64, as the generic dev_get_dstats64() consumes the starting values from dev->stats. Signed-off-by: Jeremy Kerr Reviewed-by: Simon Horman Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20240607-dstats-v3-3-cc781fe116f7@codeconstruct.com.au Signed-off-by: Jakub Kicinski --- drivers/net/vrf.c | 28 ---------------------------- 1 file changed, 28 deletions(-) diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index 5018831b2a79..9af316cdd8b3 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -137,33 +137,6 @@ static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb) kfree_skb(skb); } -static void vrf_get_stats64(struct net_device *dev, - struct rtnl_link_stats64 *stats) -{ - int i; - - for_each_possible_cpu(i) { - const struct pcpu_dstats *dstats; - u64 tbytes, tpkts, tdrops, rbytes, rpkts; - unsigned int start; - - dstats = per_cpu_ptr(dev->dstats, i); - do { - start = u64_stats_fetch_begin(&dstats->syncp); - tbytes = u64_stats_read(&dstats->tx_bytes); - tpkts = u64_stats_read(&dstats->tx_packets); - tdrops = u64_stats_read(&dstats->tx_drops); - rbytes = u64_stats_read(&dstats->rx_bytes); - rpkts = u64_stats_read(&dstats->rx_packets); - } while (u64_stats_fetch_retry(&dstats->syncp, start)); - stats->tx_bytes += tbytes; - stats->tx_packets += tpkts; - stats->tx_dropped += tdrops; - stats->rx_bytes += rbytes; - stats->rx_packets += rpkts; - } -} - static struct vrf_map *netns_vrf_map(struct net *net) { struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id); @@ -1201,7 +1174,6 @@ static const struct net_device_ops vrf_netdev_ops = { .ndo_uninit = vrf_dev_uninit, .ndo_start_xmit = vrf_xmit, .ndo_set_mac_address = eth_mac_addr, - .ndo_get_stats64 = vrf_get_stats64, .ndo_add_slave = vrf_add_slave, .ndo_del_slave = vrf_del_slave, };