linux-toradex.git/include/trace/events/tcp.h, branch v5.0

tcp: expose sk_state in tcp_retransmit_skb tracepoint

2018-09-27T03:07:19+00:00

After sk_state exposed, we can get in which state this retransmission
occurs. That could give us more detail for dignostic.
For example, if this retransmission occurs in SYN_SENT state, it may
also indicates that the syn packet may be dropped on the remote peer due
to syn backlog queue full and then we could check the remote peer.

BTW,SYNACK retransmission is traced in tcp_retransmit_synack tracepoint.

Signed-off-by: Yafang Shao 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: minor optimization around tcp_hdr() usage in receive path

2018-05-31T17:20:47+00:00

This is additional to the
commit ea1627c20c34 ("tcp: minor optimizations around tcp_hdr() usage").
At this point, skb->data is same with tcp_hdr() as tcp header has not
been pulled yet. So use the less expensive one to get the tcp header.

Remove the third parameter of tcp_rcv_established() and put it into
the function body.

Furthermore, the local variables are listed as a reverse christmas tree :)

Cc: Eric Dumazet 
Signed-off-by: Yafang Shao 
Signed-off-by: David S. Miller

tcp: use data length instead of skb->len in tcp_probe

2018-05-29T14:15:37+00:00

skb->len is meaningless to user.
data length could be more helpful, with which we can easily filter out
the packet without payload.

Signed-off-by: Yafang Shao 
Acked-by: Song Liu 
Signed-off-by: David S. Miller

net: introduce a new tracepoint for tcp_rcv_space_adjust

2018-04-23T13:58:18+00:00

tcp_rcv_space_adjust is called every time data is copied to user space,
introducing a tcp tracepoint for which could show us when the packet is
copied to user.

When a tcp packet arrives, tcp_rcv_established() will be called and with
the existed tracepoint tcp_probe we could get the time when this packet
arrives.
Then this packet will be copied to user, and tcp_rcv_space_adjust will
be called and with this new introduced tracepoint we could get the time
when this packet is copied to user.
With these two tracepoints, we could figure out whether the user program
processes this packet immediately or there's latency.

Hence in the printk message, sk_cookie is printed as a key to relate
tcp_rcv_space_adjust with tcp_probe.

Maybe we could export sockfd in this new tracepoint as well, then we
could relate this new tracepoint with epoll/read/recv* tracepoints, and
finally that could show us the whole lifespan of this packet. But we
could also implement that with pid as these functions are executed in
process context.

Signed-off-by: Yafang Shao 
Signed-off-by: David S. Miller

net: Remove unused tcp_set_state tracepoint

2018-04-16T23:02:15+00:00

This tracepoint was replaced by inet_sock_set_state in 563e0bb and not
used anywhere in the kernel anymore. Remove it.

Signed-off-by: Andrey Ignatov 
Signed-off-by: David S. Miller

net: dccp: Add DCCP sendmsg trace event

2018-01-02T19:27:30+00:00

Add DCCP sendmsg trace event (dccp/dccp_probe) for
replacing dccpprobe. User can trace this event via
ftrace or perftools.

Signed-off-by: Masami Hiramatsu 
Signed-off-by: David S. Miller

net: tcp: Add trace events for TCP congestion window tracing

2018-01-02T19:27:29+00:00

This adds an event to trace TCP stat variables with
slightly intrusive trace-event. This uses ftrace/perf
event log buffer to trace those state, no needs to
prepare own ring-buffer, nor custom user apps.

User can use ftrace to trace this event as below;

  # cd /sys/kernel/debug/tracing
  # echo 1 > events/tcp/tcp_probe/enable
  (run workloads)
  # cat trace

Signed-off-by: Masami Hiramatsu 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-12-29T20:42:26+00:00

net/ipv6/ip6_gre.c is a case of parallel adds.

include/trace/events/tcp.h is a little bit more tricky.  The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.

Signed-off-by: David S. Miller

tcp: Avoid preprocessor directives in tracepoint macro args

2017-12-26T22:25:22+00:00

Using a preprocessor directive to check for CONFIG_IPV6 in the middle of
a DECLARE_EVENT_CLASS macro's arg list causes sparse to report a series
of errors:

./include/trace/events/tcp.h:68:1: error: directive in argument list
./include/trace/events/tcp.h:75:1: error: directive in argument list
./include/trace/events/tcp.h:144:1: error: directive in argument list
./include/trace/events/tcp.h:151:1: error: directive in argument list
./include/trace/events/tcp.h:216:1: error: directive in argument list
./include/trace/events/tcp.h:223:1: error: directive in argument list
./include/trace/events/tcp.h:274:1: error: directive in argument list
./include/trace/events/tcp.h:281:1: error: directive in argument list

Once sparse finds an error, it stops printing warnings for the file it
is checking. This masks any sparse warnings that would normally be
reported for the core TCP code.

Instead, handle the preprocessor conditionals in a couple of auxiliary
macros. This also has the benefit of reducing duplicate code.

Cc: David Ahern 
Signed-off-by: Mat Martineau 
Signed-off-by: David S. Miller

net: tracepoint: replace tcp_set_state tracepoint with inet_sock_set_state tracepoint

2017-12-20T19:00:25+00:00

As sk_state is a common field for struct sock, so the state
transition tracepoint should not be a TCP specific feature.
Currently it traces all AF_INET state transition, so I rename this
tracepoint to inet_sock_set_state tracepoint with some minor changes and move it
into trace/events/sock.h.
We dont need to create a file named trace/events/inet_sock.h for this one single
tracepoint.

Two helpers are introduced to trace sk_state transition
    - void inet_sk_state_store(struct sock *sk, int newstate);
    - void inet_sk_set_state(struct sock *sk, int state);
As trace header should not be included in other header files,
so they are defined in sock.c.

The protocol such as SCTP maybe compiled as a ko, hence export
inet_sk_set_state().

Signed-off-by: Yafang Shao 
Signed-off-by: David S. Miller