linux.git/tools/bpf/bpftool/Documentation, branch v4.18

bpftool: Support sendmsg{4,6} attach types

2018-05-30T10:53:00+00:00

Add support for recently added BPF_CGROUP_UDP4_SENDMSG and
BPF_CGROUP_UDP6_SENDMSG attach types to bpftool, update documentation
and bash completion.

Signed-off-by: Andrey Ignatov 
Reviewed-by: Jakub Kicinski 
Acked-by: Song Liu 
Signed-off-by: Daniel Borkmann

tools/bpftool: add perf subcommand

2018-05-25T01:18:20+00:00

The new command "bpftool perf [show | list]" will traverse
all processes under /proc, and if any fd is associated
with a perf event, it will print out related perf event
information. Documentation is also added.

Below is an example to show the results using bcc commands.
Running the following 4 bcc commands:
  kprobe:     trace.py '__x64_sys_nanosleep'
  kretprobe:  trace.py 'r::__x64_sys_nanosleep'
  tracepoint: trace.py 't:syscalls:sys_enter_nanosleep'
  uprobe:     trace.py 'p:/home/yhs/a.out:main'

The bpftool command line and result:

  $ bpftool perf
  pid 21711  fd 5: prog_id 5  kprobe  func __x64_sys_write  offset 0
  pid 21765  fd 5: prog_id 7  kretprobe  func __x64_sys_nanosleep  offset 0
  pid 21767  fd 5: prog_id 8  tracepoint  sys_enter_nanosleep
  pid 21800  fd 5: prog_id 9  uprobe  filename /home/yhs/a.out  offset 1159

  $ bpftool -j perf
  [{"pid":21711,"fd":5,"prog_id":5,"fd_type":"kprobe","func":"__x64_sys_write","offset":0}, \
   {"pid":21765,"fd":5,"prog_id":7,"fd_type":"kretprobe","func":"__x64_sys_nanosleep","offset":0}, \
   {"pid":21767,"fd":5,"prog_id":8,"fd_type":"tracepoint","tracepoint":"sys_enter_nanosleep"}, \
   {"pid":21800,"fd":5,"prog_id":9,"fd_type":"uprobe","filename":"/home/yhs/a.out","offset":1159}]

  $ bpftool prog
  5: kprobe  name probe___x64_sys  tag e495a0c82f2c7a8d  gpl
	  loaded_at 2018-05-15T04:46:37-0700  uid 0
	  xlated 200B  not jited  memlock 4096B  map_ids 4
  7: kprobe  name probe___x64_sys  tag f2fdee479a503abf  gpl
	  loaded_at 2018-05-15T04:48:32-0700  uid 0
	  xlated 200B  not jited  memlock 4096B  map_ids 7
  8: tracepoint  name tracepoint__sys  tag 5390badef2395fcf  gpl
	  loaded_at 2018-05-15T04:48:48-0700  uid 0
	  xlated 200B  not jited  memlock 4096B  map_ids 8
  9: kprobe  name probe_main_1  tag 0a87bdc2e2953b6d  gpl
	  loaded_at 2018-05-15T04:49:52-0700  uid 0
	  xlated 200B  not jited  memlock 4096B  map_ids 9

  $ ps ax | grep "python ./trace.py"
  21711 pts/0    T      0:03 python ./trace.py __x64_sys_write
  21765 pts/0    S+     0:00 python ./trace.py r::__x64_sys_nanosleep
  21767 pts/2    S+     0:00 python ./trace.py t:syscalls:sys_enter_nanosleep
  21800 pts/3    S+     0:00 python ./trace.py p:/home/yhs/a.out:main
  22374 pts/1    S+     0:00 grep --color=auto python ./trace.py

Reviewed-by: Jakub Kicinski 
Signed-off-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov

tools: bpftool: add simple perf event output reader

2018-05-04T21:41:04+00:00

Users of BPF sooner or later discover perf_event_output() helpers
and BPF_MAP_TYPE_PERF_EVENT_ARRAY.  Dumping this array type is
not possible, however, we can add simple reading of perf events.
Create a new event_pipe subcommand for maps, this sub command
will only work with BPF_MAP_TYPE_PERF_EVENT_ARRAY maps.

Parts of the code from samples/bpf/trace_output_user.c.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Acked-by: Alexei Starovoitov 
Signed-off-by: Daniel Borkmann

tools: bpftool: fold hex keyword in command help

2018-05-04T21:41:04+00:00

Instead of spelling [hex] BYTES everywhere use DATA as keyword
for generalized value.  This will help us keep the messages
concise when longer command are added in the future.  It will
also be useful once BTF support comes.  We will only have to
change the definition of DATA.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Signed-off-by: Daniel Borkmann

tools, bpftool: Display license GPL compatible in prog show/list

2018-04-26T20:39:22+00:00

Display the license "gpl" string in bpftool prog command, like:

  # bpftool prog list
  5: tracepoint  name func  tag 57cd311f2e27366b  gpl
          loaded_at Apr 26/09:37  uid 0
          xlated 16B  not jited  memlock 4096B

  # bpftool --json --pretty prog show
  [{
          "id": 5,
          "type": "tracepoint",
          "name": "func",
          "tag": "57cd311f2e27366b",
          "gpl_compatible": true,
          "loaded_at": "Apr 26/09:37",
          "uid": 0,
          "bytes_xlated": 16,
          "jited": false,
          "bytes_memlock": 4096
      }
  ]

Signed-off-by: Jiri Olsa 
Signed-off-by: Daniel Borkmann

tools: bpftool: make it easier to feed hex bytes to bpftool

2018-04-18T12:49:27+00:00

bpftool uses hexadecimal values when it dumps map contents:

    # bpftool map dump id 1337
    key: ff 13 37 ff  value: a1 b2 c3 d4 ff ff ff ff
    Found 1 element

In order to lookup or update values with bpftool, the natural reflex is
then to copy and paste the values to the command line, and to try to run
something like:

    # bpftool map update id 1337 key ff 13 37 ff \
            value 00 00 00 00 00 00 1a 2b
    Error: error parsing byte: ff

bpftool complains, because it uses strtoul() with a 0 base to parse the
bytes, and that without a "0x" prefix, the bytes are considered as
decimal values (or even octal if they start with "0").

To feed hexadecimal values instead, one needs to add "0x" prefixes
everywhere necessary:

    # bpftool map update id 1337 key 0xff 0x13 0x37 0xff \
            value 0 0 0 0 0 0 0x1a 0x2b

To make it easier to use hexadecimal values, add an optional "hex"
keyword to put after "key" or "value" to tell bpftool to consider the
digits as hexadecimal. We can now do:

    # bpftool map update id 1337 key hex ff 13 37 ff \
            value hex 0 0 0 0 0 0 1a 2b

Without the "hex" keyword, the bytes are still parsed according to
normal integer notation (decimal if no prefix, or hexadecimal or octal
if "0x" or "0" prefix is used, respectively).

The patch also add related documentation and bash completion for the
"hex" keyword.

Suggested-by: Daniel Borkmann 
Suggested-by: David Beckett 
Signed-off-by: Quentin Monnet 
Acked-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

bpftool: Support new prog types and attach types

2018-04-18T12:39:24+00:00

Add recently added prog types to `bpftool prog` and attach types to
`bpftool cgroup`.

Update bpftool documentation and bash completion appropriately.

Signed-off-by: Andrey Ignatov 
Acked-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

tools: bpftool: new command-line option and documentation for 'visual'

2018-03-02T02:29:49+00:00

This patch adds new command-line option for visualizing the xlated eBPF
sequence.

Documentations are updated accordingly.

Usage:

  bpftool prog dump xlated id 2 visual

Reviewed-by: Quentin Monnet 
Signed-off-by: Jiong Wang 
Acked-by: Jakub Kicinski 
Signed-off-by: Alexei Starovoitov

tools: bpftool: add bash completion for cgroup commands

2018-02-08T10:59:50+00:00

Add bash completion for "bpftool cgroup" command family. While at it,
also fix the formatting of some keywords in the man page for cgroups.

Fixes: 5ccda64d38cc ("bpftool: implement cgroup bpf operations")
Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

tools: bpftool: make syntax for program map update explicit in man page

2018-02-08T10:59:50+00:00

Specify in the documentation that when using bpftool to update a map of
type BPF_MAP_TYPE_PROG_ARRAY, the syntax for the program used as a value
should use the "id|tag|pinned" keywords convention, as used with
"bpftool prog" commands.

Fixes: ff69c21a85a4 ("tools: bpftool: add documentation")
Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann