From 4323b47cf8edfe95bd58e20965667e71121c866e Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Tue, 23 Aug 2016 12:17:57 -0700 Subject: [PATCH] hv_netvsc: add ethtool statistics for tx packet issues Printing console messages is not helpful when system is out of memory; and can be disastrous with netconsole. Instead keep statistics of these anomalous conditions. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/hyperv/hyperv_net.h | 9 ++++ drivers/net/hyperv/netvsc_drv.c | 86 +++++++++++++++++++++++++++------ 2 files changed, 79 insertions(+), 16 deletions(-) diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index 8031deeb0a40..284b97b6b258 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -652,6 +652,14 @@ struct netvsc_stats { struct u64_stats_sync syncp; }; +struct netvsc_ethtool_stats { + unsigned long tx_scattered; + unsigned long tx_no_memory; + unsigned long tx_no_space; + unsigned long tx_too_big; + unsigned long tx_busy; +}; + struct netvsc_reconfig { struct list_head list; u32 event; @@ -681,6 +689,7 @@ struct net_device_context { /* Ethtool settings */ u8 duplex; u32 speed; + struct netvsc_ethtool_stats eth_stats; /* the device is going away */ bool start_remove; diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index b874ab1317c6..2360e704e271 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -365,7 +365,6 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) u32 skb_length; struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT]; struct hv_page_buffer *pb = page_buf; - struct netvsc_stats *tx_stats = this_cpu_ptr(net_device_ctx->tx_stats); /* We will atmost need two pages to describe the rndis * header. We can only transmit MAX_PAGE_BUFFER_COUNT number @@ -377,17 +376,14 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) num_data_pgs = netvsc_get_slots(skb) + 2; if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) { - if (skb_linearize(skb)) { - net_alert_ratelimited("failed to linearize skb\n"); - ret = -ENOMEM; - goto drop; - } + ++net_device_ctx->eth_stats.tx_scattered; + + if (skb_linearize(skb)) + goto no_memory; num_data_pgs = netvsc_get_slots(skb) + 2; if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) { - net_alert_ratelimited("packet too big: %u pages (%u bytes)\n", - num_data_pgs, skb->len); - ret = -EFAULT; + ++net_device_ctx->eth_stats.tx_too_big; goto drop; } } @@ -398,11 +394,9 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) * structure. */ ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE); - if (ret) { - netdev_err(net, "unable to alloc hv_netvsc_packet\n"); - ret = -ENOMEM; - goto drop; - } + if (ret) + goto no_memory; + /* Use the skb control buffer for building up the packet */ BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) > FIELD_SIZEOF(struct sk_buff, cb)); @@ -518,7 +512,7 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) ret = skb_cow_head(skb, 0); if (ret) - goto drop; + goto no_memory; uh = udp_hdr(skb); udp_len = ntohs(uh->len); @@ -545,20 +539,32 @@ do_send: ret = netvsc_send(net_device_ctx->device_ctx, packet, rndis_msg, &pb, skb); if (likely(ret == 0)) { + struct netvsc_stats *tx_stats = this_cpu_ptr(net_device_ctx->tx_stats); + u64_stats_update_begin(&tx_stats->syncp); tx_stats->packets++; tx_stats->bytes += skb_length; u64_stats_update_end(&tx_stats->syncp); return NETDEV_TX_OK; } - if (ret == -EAGAIN) + + if (ret == -EAGAIN) { + ++net_device_ctx->eth_stats.tx_busy; return NETDEV_TX_BUSY; + } + + if (ret == -ENOSPC) + ++net_device_ctx->eth_stats.tx_no_space; drop: dev_kfree_skb_any(skb); net->stats.tx_dropped++; return NETDEV_TX_OK; + +no_memory: + ++net_device_ctx->eth_stats.tx_no_memory; + goto drop; } /* @@ -1015,6 +1021,51 @@ static int netvsc_set_mac_addr(struct net_device *ndev, void *p) return err; } +static const struct { + char name[ETH_GSTRING_LEN]; + u16 offset; +} netvsc_stats[] = { + { "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) }, + { "tx_no_memory", offsetof(struct netvsc_ethtool_stats, tx_no_memory) }, + { "tx_no_space", offsetof(struct netvsc_ethtool_stats, tx_no_space) }, + { "tx_too_big", offsetof(struct netvsc_ethtool_stats, tx_too_big) }, + { "tx_busy", offsetof(struct netvsc_ethtool_stats, tx_busy) }, +}; + +static int netvsc_get_sset_count(struct net_device *dev, int string_set) +{ + switch (string_set) { + case ETH_SS_STATS: + return ARRAY_SIZE(netvsc_stats); + default: + return -EINVAL; + } +} + +static void netvsc_get_ethtool_stats(struct net_device *dev, + struct ethtool_stats *stats, u64 *data) +{ + struct net_device_context *ndc = netdev_priv(dev); + const void *nds = &ndc->eth_stats; + int i; + + for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++) + data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset); +} + +static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data) +{ + int i; + + switch (stringset) { + case ETH_SS_STATS: + for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++) + memcpy(data + i * ETH_GSTRING_LEN, + netvsc_stats[i].name, ETH_GSTRING_LEN); + break; + } +} + #ifdef CONFIG_NET_POLL_CONTROLLER static void netvsc_poll_controller(struct net_device *net) { @@ -1027,6 +1078,9 @@ static void netvsc_poll_controller(struct net_device *net) static const struct ethtool_ops ethtool_ops = { .get_drvinfo = netvsc_get_drvinfo, .get_link = ethtool_op_get_link, + .get_ethtool_stats = netvsc_get_ethtool_stats, + .get_sset_count = netvsc_get_sset_count, + .get_strings = netvsc_get_strings, .get_channels = netvsc_get_channels, .set_channels = netvsc_set_channels, .get_ts_info = ethtool_op_get_ts_info, -- 2.20.1