Re: [very-RFC 6/8] Add TSN event-tracing

From: Steven Rostedt
Date: Sun Jun 12 2016 - 12:58:27 EST


On Sun, 12 Jun 2016 01:01:34 +0200
Henrik Austad <henrik@xxxxxxxxx> wrote:

> From: Henrik Austad <haustad@xxxxxxxxx>
>
> This needs refactoring and should be updated to use TRACE_CLASS, but for
> now it provides a fair debug-window into TSN.
>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> (maintainer:TRACING)
> Cc: Ingo Molnar <mingo@xxxxxxxxxx> (maintainer:TRACING)
> Signed-off-by: Henrik Austad <haustad@xxxxxxxxx>
> ---
> include/trace/events/tsn.h | 349 +++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 349 insertions(+)
> create mode 100644 include/trace/events/tsn.h
>
> diff --git a/include/trace/events/tsn.h b/include/trace/events/tsn.h
> new file mode 100644
> index 0000000..ac1f31b
> --- /dev/null
> +++ b/include/trace/events/tsn.h
> @@ -0,0 +1,349 @@
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM tsn
> +
> +#if !defined(_TRACE_TSN_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_TSN_H
> +
> +#include <linux/tsn.h>
> +#include <linux/tracepoint.h>
> +
> +#include <linux/if_ether.h>
> +#include <linux/if_vlan.h>
> +/* #include <linux/skbuff.h> */
> +
> +/* FIXME: update to TRACE_CLASS to reduce overhead */

I'm curious to why I didn't do this now. A class would make less
duplication of typing too ;-)

> +TRACE_EVENT(tsn_buffer_write,
> +
> + TP_PROTO(struct tsn_link *link,
> + size_t bytes),
> +
> + TP_ARGS(link, bytes),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, size)
> + __field(size_t, bsize)
> + __field(size_t, size_left)
> + __field(void *, buffer)
> + __field(void *, head)
> + __field(void *, tail)
> + __field(void *, end)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->size = bytes;
> + __entry->bsize = link->used_buffer_size;
> + __entry->size_left = (link->head - link->tail) % link->used_buffer_size;

Move this logic into the print statement, since you save head and tail.

> + __entry->buffer = link->buffer;
> + __entry->head = link->head;
> + __entry->tail = link->tail;
> + __entry->end = link->end;
> + ),
> +
> + TP_printk("stream_id=%llu, copy=%zd, buffer: %zd, avail=%zd, [buffer=%p, head=%p, tail=%p, end=%p]",
> + __entry->stream_id, __entry->size, __entry->bsize, __entry->size_left,

__entry->stream_id, __entry->size, __entry->bsize,
(__entry->head - __entry->tail) % __entry->bsize,

> + __entry->buffer, __entry->head, __entry->tail, __entry->end)
> +
> + );
> +
> +TRACE_EVENT(tsn_buffer_write_net,
> +
> + TP_PROTO(struct tsn_link *link,
> + size_t bytes),
> +
> + TP_ARGS(link, bytes),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, size)
> + __field(size_t, bsize)
> + __field(size_t, size_left)
> + __field(void *, buffer)
> + __field(void *, head)
> + __field(void *, tail)
> + __field(void *, end)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->size = bytes;
> + __entry->bsize = link->used_buffer_size;
> + __entry->size_left = (link->head - link->tail) % link->used_buffer_size;
> + __entry->buffer = link->buffer;
> + __entry->head = link->head;
> + __entry->tail = link->tail;
> + __entry->end = link->end;
> + ),
> +
> + TP_printk("stream_id=%llu, copy=%zd, buffer: %zd, avail=%zd, [buffer=%p, head=%p, tail=%p, end=%p]",
> + __entry->stream_id, __entry->size, __entry->bsize, __entry->size_left,
> + __entry->buffer, __entry->head, __entry->tail, __entry->end)
> +
> + );
> +
> +
> +TRACE_EVENT(tsn_buffer_read,
> +
> + TP_PROTO(struct tsn_link *link,
> + size_t bytes),
> +
> + TP_ARGS(link, bytes),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, size)
> + __field(size_t, bsize)
> + __field(size_t, size_left)
> + __field(void *, buffer)
> + __field(void *, head)
> + __field(void *, tail)
> + __field(void *, end)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->size = bytes;
> + __entry->bsize = link->used_buffer_size;
> + __entry->size_left = (link->head - link->tail) % link->used_buffer_size;
> + __entry->buffer = link->buffer;
> + __entry->head = link->head;
> + __entry->tail = link->tail;
> + __entry->end = link->end;
> + ),
> +
> + TP_printk("stream_id=%llu, copy=%zd, buffer: %zd, avail=%zd, [buffer=%p, head=%p, tail=%p, end=%p]",
> + __entry->stream_id, __entry->size, __entry->bsize, __entry->size_left,
> + __entry->buffer, __entry->head, __entry->tail, __entry->end)
> +
> + );
> +
> +TRACE_EVENT(tsn_refill,
> +
> + TP_PROTO(struct tsn_link *link,
> + size_t reported_avail),
> +
> + TP_ARGS(link, reported_avail),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, bsize)
> + __field(size_t, size_left)
> + __field(size_t, reported_left)
> + __field(size_t, low_water)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->bsize = link->used_buffer_size;
> + __entry->size_left = (link->head - link->tail) % link->used_buffer_size;

As you don't save head and tail here, this logic needs to remain.

> + __entry->reported_left = reported_avail;
> + __entry->low_water = link->low_water_mark;
> + ),
> +
> + TP_printk("stream_id=%llu, buffer=%zd, avail=%zd, reported=%zd, low=%zd",
> + __entry->stream_id, __entry->bsize, __entry->size_left, __entry->reported_left, __entry->low_water)
> + );
> +
> +TRACE_EVENT(tsn_send_batch,
> +
> + TP_PROTO(struct tsn_link *link,
> + int num_send,
> + u64 ts_base_ns,
> + u64 ts_delta_ns),
> +
> + TP_ARGS(link, num_send, ts_base_ns, ts_delta_ns),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(int, seqnr)
> + __field(int, num_send)
> + __field(u64, ts_base_ns)
> + __field(u64, ts_delta_ns)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->seqnr = (int)link->last_seqnr;
> + __entry->ts_base_ns = ts_base_ns;
> + __entry->ts_delta_ns = ts_delta_ns;
> + __entry->num_send = num_send;
> + ),
> +
> + TP_printk("stream_id=%llu, seqnr=%d, num_send=%d, ts_base_ns=%llu, ts_delta_ns=%llu",
> + __entry->stream_id, __entry->seqnr, __entry->num_send, __entry->ts_base_ns, __entry->ts_delta_ns)
> + );
> +
> +
> +TRACE_EVENT(tsn_rx_handler,
> +
> + TP_PROTO(struct tsn_link *link,
> + const struct ethhdr *ethhdr,
> + u64 sid),
> +
> + TP_ARGS(link, ethhdr, sid),
> +
> + TP_STRUCT__entry(
> + __field(char *, name)
> + __field(u16, proto)
> + __field(u64, sid)
> + __field(u64, link_sid)
> + ),
> + TP_fast_assign(
> + __entry->name = link->nic->name;
> + __entry->proto = ethhdr->h_proto;
> + __entry->sid = sid;
> + __entry->link_sid = link->stream_id;
> + ),
> +
> + TP_printk("name=%s, proto: 0x%04x, stream_id=%llu, link->sid=%llu",
> + __entry->name, ntohs(__entry->proto), __entry->sid, __entry->link_sid)
> + );
> +
> +TRACE_EVENT(tsn_du,
> +
> + TP_PROTO(struct tsn_link *link,
> + size_t bytes),
> +
> + TP_ARGS(link, bytes),
> +
> + TP_STRUCT__entry(
> + __field(u64, link_sid)
> + __field(size_t, bytes)
> + ),
> + TP_fast_assign(
> + __entry->link_sid = link->stream_id;
> + __entry->bytes = bytes;
> + ),
> +
> + TP_printk("stream_id=%llu,bytes=%zu",
> + __entry->link_sid, __entry->bytes)
> +);
> +
> +TRACE_EVENT(tsn_set_buffer,
> +
> + TP_PROTO(struct tsn_link *link, size_t bufsize),
> +
> + TP_ARGS(link, bufsize),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, size)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->size = bufsize;
> + ),
> +
> + TP_printk("stream_id=%llu,buffer_size=%zu",
> + __entry->stream_id, __entry->size)
> +
> + );
> +
> +TRACE_EVENT(tsn_free_buffer,
> +
> + TP_PROTO(struct tsn_link *link),
> +
> + TP_ARGS(link),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, bufsize)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->bufsize = link->buffer_size;
> + ),
> +
> + TP_printk("stream_id=%llu,size:%zd",
> + __entry->stream_id, __entry->bufsize)
> +
> + );
> +
> +TRACE_EVENT(tsn_buffer_drain,
> +
> + TP_PROTO(struct tsn_link *link, size_t used),
> +
> + TP_ARGS(link, used),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(size_t, used)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->used = used;
> + ),
> +
> + TP_printk("stream_id=%llu,used=%zu",
> + __entry->stream_id, __entry->used)
> +
> +);
> +/* TODO: too long, need cleanup.
> + */
> +TRACE_EVENT(tsn_pre_tx,
> +
> + TP_PROTO(struct tsn_link *link, struct sk_buff *skb, size_t bytes),
> +
> + TP_ARGS(link, skb, bytes),
> +
> + TP_STRUCT__entry(
> + __field(u64, stream_id)
> + __field(u32, vlan_tag)
> + __field(size_t, bytes)
> + __field(size_t, data_len)
> + __field(unsigned int, headlen)
> + __field(u16, protocol)
> + __field(u16, prot_native)
> + __field(int, tx_idx)
> + __field(u16, mac_len)
> + __field(u16, hdr_len)
> + __field(u16, vlan_tci)
> + __field(u16, mac_header)
> + __field(unsigned int, tail)
> + __field(unsigned int, end)
> + __field(unsigned int, truesize)
> + ),
> +
> + TP_fast_assign(
> + __entry->stream_id = link->stream_id;
> + __entry->vlan_tag = (skb_vlan_tag_present(skb) ? skb_vlan_tag_get(skb) : 0);
> + __entry->bytes = bytes;
> + __entry->data_len = skb->data_len;
> + __entry->headlen = skb_headlen(skb);
> + __entry->protocol = ntohs(vlan_get_protocol(skb));

Maybe it would be better to do the ntohs() in the TP_printk() as well.

> + __entry->prot_native = ntohs(skb->protocol);

here too.

> + __entry->tx_idx = skb_get_queue_mapping(skb);
> +
> + __entry->mac_len = skb->mac_len;
> + __entry->hdr_len = skb->hdr_len;
> + __entry->vlan_tci = skb->vlan_tci;
> + __entry->mac_header = skb->mac_header;
> + __entry->tail = (unsigned int)skb->tail;
> + __entry->end = (unsigned int)skb->end;
> + __entry->truesize = skb->truesize;
> + ),
> +
> + TP_printk("stream_id=%llu,vlan_tag=0x%04x,data_size=%zd,data_len=%zd,headlen=%u,proto=0x%04x (0x%04x),tx_idx=%d,mac_len=%u,hdr_len=%u,vlan_tci=0x%02x,mac_header=0x%02x,tail=%u,end=%u,truesize=%u",
> + __entry->stream_id,
> + __entry->vlan_tag,
> + __entry->bytes,
> + __entry->data_len,
> + __entry->headlen,
> + __entry->protocol,
> + __entry->prot_native, __entry->tx_idx,
> + __entry->mac_len,
> + __entry->hdr_len,
> + __entry->vlan_tci,
> + __entry->mac_header,

Is this an ether mac header? If so we support %M. But as it's defined
as only u16, it doesn't seem like it can be.

-- Steve

> + __entry->tail,
> + __entry->end,
> + __entry->truesize)
> + );
> +
> +#endif /* _TRACE_TSN_H || TRACE_HEADER_MULTI_READ */
> +
> +#include <trace/define_trace.h>