Merge branch 'netdev_tracing'

Ben Hutchings says:

====================
Improve tracing at the driver/core boundary

These patches add static tracpeoints at the driver/core boundary which
record various skb fields likely to be useful for datapath debugging.
On the TX side the boundary is where the core calls ndo_start_xmit, and
on the RX side it is where any of the various exported receive functions
is called.

The set of skb fields is mostly based on what I thought would be
interesting for sfc.

These patches are basically the same as what I sent as an RFC in
November, but rebased.  They now depend on 'net: core: explicitly select
a txq before doing l2 forwarding', so please merge net into net-next
before trying to apply them.  The first patch fixes a code formatting
error left behind after that fix.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2014-01-14 14:46:13 -08:00
commit c49fa01663
2 changed files with 222 additions and 41 deletions

View File

@ -6,9 +6,67 @@
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/ip.h>
#include <linux/tracepoint.h>
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,
@ -78,6 +136,106 @@ DEFINE_EVENT(net_dev_template, netif_rx,
TP_ARGS(skb)
);
DECLARE_EVENT_CLASS(net_dev_rx_verbose_template,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb),
TP_STRUCT__entry(
__string( name, skb->dev->name )
__field( unsigned int, napi_id )
__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( u32, rxhash )
__field( bool, l4_rxhash )
__field( unsigned int, len )
__field( unsigned int, data_len )
__field( unsigned int, truesize )
__field( bool, mac_header_valid)
__field( int, mac_header )
__field( unsigned char, nr_frags )
__field( u16, gso_size )
__field( u16, gso_type )
),
TP_fast_assign(
__assign_str(name, skb->dev->name);
#ifdef CONFIG_NET_RX_BUSY_POLL
__entry->napi_id = skb->napi_id;
#else
__entry->napi_id = 0;
#endif
__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->rxhash = skb->rxhash;
__entry->l4_rxhash = skb->l4_rxhash;
__entry->len = skb->len;
__entry->data_len = skb->data_len;
__entry->truesize = skb->truesize;
__entry->mac_header_valid = skb_mac_header_was_set(skb);
__entry->mac_header = skb_mac_header(skb) - skb->data;
__entry->nr_frags = skb_shinfo(skb)->nr_frags;
__entry->gso_size = skb_shinfo(skb)->gso_size;
__entry->gso_type = skb_shinfo(skb)->gso_type;
),
TP_printk("dev=%s napi_id=%#x queue_mapping=%u skbaddr=%p vlan_tagged=%d vlan_proto=0x%04x vlan_tci=0x%04x protocol=0x%04x ip_summed=%d rxhash=0x%08x l4_rxhash=%d len=%u data_len=%u truesize=%u mac_header_valid=%d mac_header=%d nr_frags=%d gso_size=%d gso_type=%#x",
__get_str(name), __entry->napi_id, __entry->queue_mapping,
__entry->skbaddr, __entry->vlan_tagged, __entry->vlan_proto,
__entry->vlan_tci, __entry->protocol, __entry->ip_summed,
__entry->rxhash, __entry->l4_rxhash, __entry->len,
__entry->data_len, __entry->truesize,
__entry->mac_header_valid, __entry->mac_header,
__entry->nr_frags, __entry->gso_size, __entry->gso_type)
);
DEFINE_EVENT(net_dev_rx_verbose_template, napi_gro_frags_entry,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb)
);
DEFINE_EVENT(net_dev_rx_verbose_template, napi_gro_receive_entry,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb)
);
DEFINE_EVENT(net_dev_rx_verbose_template, netif_receive_skb_entry,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb)
);
DEFINE_EVENT(net_dev_rx_verbose_template, netif_rx_entry,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb)
);
DEFINE_EVENT(net_dev_rx_verbose_template, netif_rx_ni_entry,
TP_PROTO(const struct sk_buff *skb),
TP_ARGS(skb)
);
#endif /* _TRACE_NET_H */
/* This part must be outside protection */

View File

@ -147,6 +147,8 @@ struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
struct list_head ptype_all __read_mostly; /* Taps */
static struct list_head offload_base __read_mostly;
static int netif_rx_internal(struct sk_buff *skb);
/*
* The @dev_base_head list is protected by @dev_base_lock and the rtnl
* semaphore.
@ -1698,7 +1700,7 @@ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
skb_scrub_packet(skb, true);
skb->protocol = eth_type_trans(skb, dev);
return netif_rx(skb);
return netif_rx_internal(skb);
}
EXPORT_SYMBOL_GPL(dev_forward_skb);
@ -2596,8 +2598,8 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
dev_queue_xmit_nit(skb, dev);
skb_len = skb->len;
rc = ops->ndo_start_xmit(skb, dev);
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)
txq_trans_update(txq);
@ -2615,6 +2617,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
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)) {
@ -3218,22 +3221,7 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
return NET_RX_DROP;
}
/**
* netif_rx - post buffer to the network code
* @skb: buffer to post
*
* This function receives a packet from a device driver and queues it for
* the upper (protocol) levels to process. It always succeeds. The buffer
* may be dropped during processing for congestion control or by the
* protocol layers.
*
* return values:
* NET_RX_SUCCESS (no congestion)
* NET_RX_DROP (packet was dropped)
*
*/
int netif_rx(struct sk_buff *skb)
static int netif_rx_internal(struct sk_buff *skb)
{
int ret;
@ -3269,14 +3257,38 @@ int netif_rx(struct sk_buff *skb)
}
return ret;
}
/**
* netif_rx - post buffer to the network code
* @skb: buffer to post
*
* This function receives a packet from a device driver and queues it for
* the upper (protocol) levels to process. It always succeeds. The buffer
* may be dropped during processing for congestion control or by the
* protocol layers.
*
* return values:
* NET_RX_SUCCESS (no congestion)
* NET_RX_DROP (packet was dropped)
*
*/
int netif_rx(struct sk_buff *skb)
{
trace_netif_rx_entry(skb);
return netif_rx_internal(skb);
}
EXPORT_SYMBOL(netif_rx);
int netif_rx_ni(struct sk_buff *skb)
{
int err;
trace_netif_rx_ni_entry(skb);
preempt_disable();
err = netif_rx(skb);
err = netif_rx_internal(skb);
if (local_softirq_pending())
do_softirq();
preempt_enable();
@ -3661,22 +3673,7 @@ static int __netif_receive_skb(struct sk_buff *skb)
return ret;
}
/**
* netif_receive_skb - process receive buffer from network
* @skb: buffer to process
*
* netif_receive_skb() is the main receive data processing function.
* It always succeeds. The buffer may be dropped during processing
* for congestion control or by the protocol layers.
*
* This function may only be called from softirq context and interrupts
* should be enabled.
*
* Return values (usually ignored):
* NET_RX_SUCCESS: no congestion
* NET_RX_DROP: packet was dropped
*/
int netif_receive_skb(struct sk_buff *skb)
static int netif_receive_skb_internal(struct sk_buff *skb)
{
net_timestamp_check(netdev_tstamp_prequeue, skb);
@ -3702,6 +3699,28 @@ int netif_receive_skb(struct sk_buff *skb)
#endif
return __netif_receive_skb(skb);
}
/**
* netif_receive_skb - process receive buffer from network
* @skb: buffer to process
*
* netif_receive_skb() is the main receive data processing function.
* It always succeeds. The buffer may be dropped during processing
* for congestion control or by the protocol layers.
*
* This function may only be called from softirq context and interrupts
* should be enabled.
*
* Return values (usually ignored):
* NET_RX_SUCCESS: no congestion
* NET_RX_DROP: packet was dropped
*/
int netif_receive_skb(struct sk_buff *skb)
{
trace_netif_receive_skb_entry(skb);
return netif_receive_skb_internal(skb);
}
EXPORT_SYMBOL(netif_receive_skb);
/* Network device is going away, flush any packets still pending
@ -3763,7 +3782,7 @@ static int napi_gro_complete(struct sk_buff *skb)
}
out:
return netif_receive_skb(skb);
return netif_receive_skb_internal(skb);
}
/* napi->gro_list contains packets ordered by age.
@ -3971,7 +3990,7 @@ static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
{
switch (ret) {
case GRO_NORMAL:
if (netif_receive_skb(skb))
if (netif_receive_skb_internal(skb))
ret = GRO_DROP;
break;
@ -3996,6 +4015,8 @@ static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
{
trace_napi_gro_receive_entry(skb);
return napi_skb_finish(dev_gro_receive(napi, skb), skb);
}
EXPORT_SYMBOL(napi_gro_receive);
@ -4029,7 +4050,7 @@ static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *
{
switch (ret) {
case GRO_NORMAL:
if (netif_receive_skb(skb))
if (netif_receive_skb_internal(skb))
ret = GRO_DROP;
break;
@ -4068,6 +4089,8 @@ gro_result_t napi_gro_frags(struct napi_struct *napi)
if (!skb)
return GRO_DROP;
trace_napi_gro_frags_entry(skb);
return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
}
EXPORT_SYMBOL(napi_gro_frags);
@ -6620,11 +6643,11 @@ static int dev_cpu_callback(struct notifier_block *nfb,
/* Process offline CPU's input_pkt_queue */
while ((skb = __skb_dequeue(&oldsd->process_queue))) {
netif_rx(skb);
netif_rx_internal(skb);
input_queue_head_incr(oldsd);
}
while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
netif_rx(skb);
netif_rx_internal(skb);
input_queue_head_incr(oldsd);
}