From d87d04a7851f067a06bb10acca8aca62a8cad6f0 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Fri, 10 Jan 2014 22:17:03 +0000 Subject: [PATCH] net: Add net_dev_start_xmit trace event, exposing more skb fields The existing net/net_dev_xmit trace event provides little information about the skb that has been passed to the driver, and it is not simple to add more since the skb may already have been freed at the point the event is emitted. Add a separate trace event before the skb is passed to the driver, including most fields that are likely to be interesting for debugging driver datapath behaviour. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller --- include/trace/events/net.h | 58 ++++++++++++++++++++++++++++++++++++++ net/core/dev.c | 2 ++ 2 files changed, 60 insertions(+) diff --git a/include/trace/events/net.h b/include/trace/events/net.h index f99645d05a8f..7a72f44ae6ab 100644 --- a/include/trace/events/net.h +++ b/include/trace/events/net.h @@ -6,9 +6,67 @@ #include #include +#include #include #include +TRACE_EVENT(net_dev_start_xmit, + + TP_PROTO(const struct sk_buff *skb, const struct net_device *dev), + + TP_ARGS(skb, dev), + + TP_STRUCT__entry( + __string( name, dev->name ) + __field( u16, queue_mapping ) + __field( const void *, skbaddr ) + __field( bool, vlan_tagged ) + __field( u16, vlan_proto ) + __field( u16, vlan_tci ) + __field( u16, protocol ) + __field( u8, ip_summed ) + __field( unsigned int, len ) + __field( unsigned int, data_len ) + __field( int, network_offset ) + __field( bool, transport_offset_valid) + __field( int, transport_offset) + __field( u8, tx_flags ) + __field( u16, gso_size ) + __field( u16, gso_segs ) + __field( u16, gso_type ) + ), + + TP_fast_assign( + __assign_str(name, dev->name); + __entry->queue_mapping = skb->queue_mapping; + __entry->skbaddr = skb; + __entry->vlan_tagged = vlan_tx_tag_present(skb); + __entry->vlan_proto = ntohs(skb->vlan_proto); + __entry->vlan_tci = vlan_tx_tag_get(skb); + __entry->protocol = ntohs(skb->protocol); + __entry->ip_summed = skb->ip_summed; + __entry->len = skb->len; + __entry->data_len = skb->data_len; + __entry->network_offset = skb_network_offset(skb); + __entry->transport_offset_valid = + skb_transport_header_was_set(skb); + __entry->transport_offset = skb_transport_offset(skb); + __entry->tx_flags = skb_shinfo(skb)->tx_flags; + __entry->gso_size = skb_shinfo(skb)->gso_size; + __entry->gso_segs = skb_shinfo(skb)->gso_segs; + __entry->gso_type = skb_shinfo(skb)->gso_type; + ), + + TP_printk("dev=%s queue_mapping=%u skbaddr=%p vlan_tagged=%d vlan_proto=0x%04x vlan_tci=0x%04x protocol=0x%04x ip_summed=%d len=%u data_len=%u network_offset=%d transport_offset_valid=%d transport_offset=%d tx_flags=%d gso_size=%d gso_segs=%d gso_type=%#x", + __get_str(name), __entry->queue_mapping, __entry->skbaddr, + __entry->vlan_tagged, __entry->vlan_proto, __entry->vlan_tci, + __entry->protocol, __entry->ip_summed, __entry->len, + __entry->data_len, + __entry->network_offset, __entry->transport_offset_valid, + __entry->transport_offset, __entry->tx_flags, + __entry->gso_size, __entry->gso_segs, __entry->gso_type) +); + TRACE_EVENT(net_dev_xmit, TP_PROTO(struct sk_buff *skb, diff --git a/net/core/dev.c b/net/core/dev.c index 0703ee04c670..9e93a1464216 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2596,6 +2596,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, dev_queue_xmit_nit(skb, dev); skb_len = skb->len; + trace_net_dev_start_xmit(skb, dev); rc = ops->ndo_start_xmit(skb, dev); trace_net_dev_xmit(skb, rc, dev, skb_len); if (rc == NETDEV_TX_OK) @@ -2614,6 +2615,7 @@ gso: dev_queue_xmit_nit(nskb, dev); skb_len = nskb->len; + trace_net_dev_start_xmit(nskb, dev); rc = ops->ndo_start_xmit(nskb, dev); trace_net_dev_xmit(nskb, rc, dev, skb_len); if (unlikely(rc != NETDEV_TX_OK)) {