Provided by: linux-tools-common_6.2.0-20.20_all bug

NAME

       bpftool-prog - tool for inspection and simple manipulation of eBPF progs

SYNOPSIS

          bpftool [OPTIONS] prog COMMAND

          OPTIONS  := { { -j | --json } [{ -p | --pretty }] | { -d | --debug } | { -f | --bpffs }
          | { -m | --mapcompat } | { -n | --nomount } | { -L | --use-loader } }

          COMMANDS := { show | list | dump xlated | dump jited | pin | load | loadall | help }

PROG COMMANDS

       bpftool prog { show | list } [PROG]
       bpftool prog dump xlated PROG [{file FILE | opcodes | visual | linum}]
       bpftool prog dump jited  PROG [{file FILE | opcodes | linum}]
       bpftool prog pin PROG FILE
       bpftool prog { load | loadall } OBJ PATH [type TYPE] [map {idx IDX | name NAME} MAP] [dev NAME] [pinmaps MAP_DIR] [autoattach]
       bpftool prog attach PROG ATTACH_TYPE [MAP]
       bpftool prog detach PROG ATTACH_TYPE [MAP]
       bpftool prog tracelog
       bpftool prog run PROG data_in FILE [data_out FILE [data_size_out L]] [ctx_in FILE [ctx_out FILE [ctx_size_out M]]] [repeat N]
       bpftool prog profile PROG [duration DURATION] METRICs
       bpftool prog help

       MAP := { id MAP_ID | pinned FILE }
       PROG := { id PROG_ID | pinned FILE | tag PROG_TAG | name PROG_NAME }
       TYPE := {
         socket | kprobe | kretprobe | classifier | action |
         tracepoint | raw_tracepoint | xdp | perf_event | cgroup/skb |
         cgroup/sock | cgroup/dev | lwt_in | lwt_out | lwt_xmit |
         lwt_seg6local | sockops | sk_skb | sk_msg | lirc_mode2 |
         cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 | cgroup/post_bind6 |
         cgroup/connect4 | cgroup/connect6 | cgroup/getpeername4 | cgroup/getpeername6 |
         cgroup/getsockname4 | cgroup/getsockname6 | cgroup/sendmsg4 | cgroup/sendmsg6 |
         cgroup/recvmsg4 | cgroup/recvmsg6 | cgroup/sysctl |
         cgroup/getsockopt | cgroup/setsockopt | cgroup/sock_release |
         struct_ops | fentry | fexit | freplace | sk_lookup
       }
       ATTACH_TYPE := {
         sk_msg_verdict | sk_skb_verdict | sk_skb_stream_verdict |
         sk_skb_stream_parser | flow_dissector
       }
       METRICs := {
         cycles | instructions | l1d_loads | llc_misses |
         itlb_misses | dtlb_misses
       }

DESCRIPTION

          bpftool prog { show | list } [PROG]
                 Show information about loaded programs.  If PROG is specified  show  information
                 only  about  given programs, otherwise list all programs currently loaded on the
                 system.  In case of tag or name, PROG may match several programs which will  all
                 be shown.

                 Output  will  start  with  program  ID followed by program type and zero or more
                 named attributes (depending on kernel version).

                 Since Linux 5.1 the kernel can collect statistics on BPF programs (such  as  the
                 total  time  spent  running the program, and the number of times it was run). If
                 available, bpftool shows such statistics. However, the kernel does  not  collect
                 them  by  defaults,  as  it  slightly  impacts  performance on each program run.
                 Activation   or   deactivation   of   the   feature   is   performed   via   the
                 kernel.bpf_stats_enabled sysctl knob.

                 Since  Linux  5.8  bpftool  is able to discover information about processes that
                 hold open file descriptors (FDs) against BPF programs. On such  kernels  bpftool
                 will automatically emit this information as well.

          bpftool prog dump xlated PROG [{ file FILE | opcodes | visual | linum }]
                 Dump eBPF instructions of the programs from the kernel. By default, eBPF will be
                 disassembled and printed to standard output in human-readable  format.  In  this
                 case, opcodes controls if raw opcodes should be printed as well.

                 In  case  of  tag  or  name,  PROG  may match several programs which will all be
                 dumped.  However, if file or visual is  specified,  PROG  must  match  a  single
                 program.

                 If file is specified, the binary image will instead be written to FILE.

                 If visual is specified, control flow graph (CFG) will be built instead, and eBPF
                 instructions will be presented with CFG in DOT format, on standard output.

                 If the programs have line_info available, the source line will be  displayed  by
                 default.   If linum is specified, the filename, line number and line column will
                 also be displayed on top of the source line.

          bpftool prog dump jited PROG [{ file FILE | opcodes | linum }]
                 Dump jited image (host machine code) of the program.

                 If FILE is specified image will be written to  a  file,  otherwise  it  will  be
                 disassembled  and printed to stdout.  PROG must match a single program when file
                 is specified.

                 opcodes controls if raw opcodes will be printed.

                 If the prog has line_info available,  the  source  line  will  be  displayed  by
                 default.   If linum is specified, the filename, line number and line column will
                 also be displayed on top of the source line.

          bpftool prog pin PROG FILE
                 Pin program PROG as FILE.

                 Note: FILE must be located in bpffs mount. It must not contain a  dot  character
                 ('.'), which is reserved for future extensions of bpffs.

          bpftool  prog  {  load | loadall } OBJ PATH [type TYPE] [map {idx IDX | name NAME} MAP]
          [dev NAME] [pinmaps MAP_DIR] [autoattach]
                 Load bpf program(s) from binary OBJ and pin as PATH.   bpftool  prog  load  pins
                 only  the  first  program  from  the  OBJ as PATH. bpftool prog loadall pins all
                 programs from the OBJ under PATH directory.  type is optional, if not  specified
                 program  type  will  be  inferred  from  section names.  By default bpftool will
                 create new maps as declared in the  ELF  object  being  loaded.   map  parameter
                 allows for the reuse of existing maps.  It can be specified multiple times, each
                 time for a different map.  IDX refers to index of the map to be replaced in  the
                 ELF  file  counting  from  0,  while  NAME allows to replace a map by name.  MAP
                 specifies the map to use, referring to it by id or through a  pinned  file.   If
                 dev  NAME  is  specified  program  will  be  loaded onto given networking device
                 (offload).  Optional pinmaps argument can be provided  to  pin  all  maps  under
                 MAP_DIR directory.

                 If  autoattach  is  specified program will be attached before pin. In that case,
                 only the link (representing the program attached to its hook) is pinned, not the
                 program  as  such,  so the path won't show in bpftool prog show -f, only show in
                 bpftool link show -f. Also, this only works when bpftool  (libbpf)  is  able  to
                 infer  all  necessary  information from the object file, in particular, it's not
                 supported for all program types. If  a  program  does  not  support  autoattach,
                 bpftool falls back to regular pinning for that program instead.

                 Note:  PATH  must be located in bpffs mount. It must not contain a dot character
                 ('.'), which is reserved for future extensions of bpffs.

          bpftool prog attach PROG ATTACH_TYPE [MAP]
                 Attach bpf program PROG (with type specified by ATTACH_TYPE). Most  ATTACH_TYPEs
                 require  a MAP parameter, with the exception of flow_dissector which is attached
                 to current networking name space.

          bpftool prog detach PROG ATTACH_TYPE [MAP]
                 Detach bpf program PROG (with type specified by ATTACH_TYPE). Most  ATTACH_TYPEs
                 require  a MAP parameter, with the exception of flow_dissector which is detached
                 from the current networking name space.

          bpftool prog tracelog
                 Dump the trace pipe of the system to the console (stdout).  Hit <Ctrl+C> to stop
                 printing.  BPF  programs  can  write  to  this  trace  pipe  at runtime with the
                 bpf_trace_printk() helper.  This should be used only for debugging purposes. For
                 streaming  data  from  BPF  programs to user space, one can use perf events (see
                 also bpftool-map(8)).

          bpftool prog run PROG data_in FILE  [data_out  FILE  [data_size_out  L]]  [ctx_in  FILE
          [ctx_out FILE [ctx_size_out M]]] [repeat N]
                 Run  BPF program PROG in the kernel testing infrastructure for BPF, meaning that
                 the program works on the data and context provided  by  the  user,  and  not  on
                 actual  packets  or  monitored  functions etc. Return value and duration for the
                 test run are printed out to the console.

                 Input data is read from the FILE passed with data_in.   If  this  FILE  is  "-",
                 input data is read from standard input. Input context, if any, is read from FILE
                 passed with ctx_in. Again, "-" can be used to read from standard input, but only
                 if standard input is not already in use for input data. If a FILE is passed with
                 data_out, output data is written to that  file.  Similarly,  output  context  is
                 written  to the FILE passed with ctx_out. For both output flows, "-" can be used
                 to print to the standard output (as plain text, or JSON if relevant  option  was
                 passed).  If output keywords are omitted, output data and context are discarded.
                 Keywords data_size_out and ctx_size_out are used to pass the size (in bytes) for
                 the  output  buffers to the kernel, although the default of 32 kB should be more
                 than enough for most cases.

                 Keyword repeat is used to indicate the number of consecutive  runs  to  perform.
                 Note  that  output  data  and context printed to files correspond to the last of
                 those runs. The duration printed out at the end of the runs is an  average  over
                 all runs performed by the command.

                 Not  all  program  types support test run. Among those which do, not all of them
                 can take the ctx_in/ctx_out  arguments.  bpftool  does  not  perform  checks  on
                 program types.

          bpftool prog profile PROG [duration DURATION] METRICs
                 Profile  METRICs  for  bpf  program PROG for DURATION seconds or until user hits
                 <Ctrl+C>. DURATION is optional.  If DURATION is  not  specified,  the  profiling
                 will run up to UINT_MAX seconds.

          bpftool prog help
                 Print short help message.

OPTIONS

          -h, --help
                 Print short help message (similar to bpftool help).

          -V, --version
                 Print  bpftool's  version number (similar to bpftool version), the number of the
                 libbpf version in use, and optional features that were included when bpftool was
                 compiled.  Optional  features  include linking against LLVM or libbfd to provide
                 the disassembler for JIT-ted programs (bpftool prog dump jited) and usage of BPF
                 skeletons (some features like bpftool prog profile or showing pids associated to
                 BPF objects may rely on it).

          -j, --json
                 Generate JSON output. For commands that cannot produce JSON, this option has  no
                 effect.

          -p, --pretty
                 Generate human-readable JSON output. Implies -j.

          -d, --debug
                 Print  all logs available, even debug-level information. This includes logs from
                 libbpf as well as from the verifier, when attempting to load programs.

          -f, --bpffs
                 When showing BPF programs, show file names of pinned programs.

          -m, --mapcompat
                 Allow loading maps with unknown map definitions.

          -n, --nomount
                 Do not automatically attempt to mount any virtual file system (such  as  tracefs
                 or BPF virtual file system) when necessary.

          -L, --use-loader
                 Load  program  as  a "loader" program. This is useful to debug the generation of
                 such programs. When this option is in use, bpftool attempts to load the programs
                 from the object file into the kernel, but does not pin them (therefore, the PATH
                 must not be provided).

                 When  combined  with  the  -d|--debug  option,  additional  debug  messages  are
                 generated,   and   the   execution   of   the   loader   program  will  use  the
                 bpf_trace_printk() helper to log each step of loading BTF,  creating  the  maps,
                 and  loading  the  programs  (see  bpftool  prog tracelog as a way to dump those
                 messages).

EXAMPLES

       # bpftool prog show

          10: xdp  name some_prog  tag 005a3d2123620c8b  gpl run_time_ns 81632 run_cnt 10
                  loaded_at 2017-09-29T20:11:00+0000  uid 0
                  xlated 528B  jited 370B  memlock 4096B  map_ids 10
                  pids systemd(1)

       # bpftool --json --pretty prog show

          [{
                  "id": 10,
                  "type": "xdp",
                  "tag": "005a3d2123620c8b",
                  "gpl_compatible": true,
                  "run_time_ns": 81632,
                  "run_cnt": 10,
                  "loaded_at": 1506715860,
                  "uid": 0,
                  "bytes_xlated": 528,
                  "jited": true,
                  "bytes_jited": 370,
                  "bytes_memlock": 4096,
                  "map_ids": [10
                  ],
                  "pids": [{
                          "pid": 1,
                          "comm": "systemd"
                      }
                  ]
              }
          ]

       # bpftool prog dump xlated id 10 file /tmp/t
       $ ls -l /tmp/t

          -rw------- 1 root root 560 Jul 22 01:42 /tmp/t

       # bpftool prog dump jited tag 005a3d2123620c8b

          0:   push   %rbp
          1:   mov    %rsp,%rbp
          2:   sub    $0x228,%rsp
          3:   sub    $0x28,%rbp
          4:   mov    %rbx,0x0(%rbp)

       # mount -t bpf none /sys/fs/bpf/
       # bpftool prog pin id 10 /sys/fs/bpf/prog
       # bpftool prog load ./my_prog.o /sys/fs/bpf/prog2
       # ls -l /sys/fs/bpf/

          -rw------- 1 root root 0 Jul 22 01:43 prog
          -rw------- 1 root root 0 Jul 22 01:44 prog2

       # bpftool prog dump jited pinned /sys/fs/bpf/prog opcodes

          0:   push   %rbp
               55
          1:   mov    %rsp,%rbp
               48 89 e5
          4:   sub    $0x228,%rsp
               48 81 ec 28 02 00 00
          b:   sub    $0x28,%rbp
               48 83 ed 28
          f:   mov    %rbx,0x0(%rbp)
               48 89 5d 00

       # bpftool prog load xdp1_kern.o /sys/fs/bpf/xdp1 type xdp map name rxcnt id 7
       # bpftool prog show pinned /sys/fs/bpf/xdp1

          9: xdp  name xdp_prog1  tag 539ec6ce11b52f98  gpl
                  loaded_at 2018-06-25T16:17:31-0700  uid 0
                  xlated 488B  jited 336B  memlock 4096B  map_ids 7

       # rm /sys/fs/bpf/xdp1

       # bpftool prog profile id 337 duration 10 cycles instructions llc_misses

             51397 run_cnt
          40176203 cycles                                                 (83.05%)
          42518139 instructions    #   1.06 insns per cycle               (83.39%)
               123 llc_misses      #   2.89 LLC misses per million insns  (83.15%)

       Output below is for the trace logs.
       Run in separate terminals:
       # bpftool prog tracelog
       # bpftool prog load -L -d file.o

          bpftool-620059  [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5
          bpftool-620059  [004] d... 2634685.517912: bpf_trace_printk: map_create sample_map idx 0 type 2 value_size 4 value_btf_id 0 r=6
          bpftool-620059  [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7
          bpftool-620059  [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0

SEE ALSO

          bpf(2),     bpf-helpers(7),     bpftool(8),     bpftool-btf(8),      bpftool-cgroup(8),
          bpftool-feature(8),  bpftool-gen(8),  bpftool-iter(8), bpftool-link(8), bpftool-map(8),
          bpftool-net(8), bpftool-perf(8), bpftool-struct_ops(8)

                                                                                  BPFTOOL-PROG(8)