linux/tools/bpf/bpftool
Sandipan Das f7f62c7134 tools: bpftool: add delimiters to multi-function JITed dumps
This splits up the contiguous JITed dump obtained via the bpf
system call into more relatable chunks for each function in
the program. If the kernel symbols corresponding to these are
known, they are printed in the header for each JIT image dump
otherwise the masked start address is printed.

Before applying this patch:

  # bpftool prog dump jited id 1

     0:	push   %rbp
     1:	mov    %rsp,%rbp
  ...
    70:	leaveq
    71:	retq
    72:	push   %rbp
    73:	mov    %rsp,%rbp
  ...
    dd:	leaveq
    de:	retq

  # bpftool -p prog dump jited id 1

  [{
          "pc": "0x0",
          "operation": "push",
          "operands": ["%rbp"
          ]
      },{
  ...
      },{
          "pc": "0x71",
          "operation": "retq",
          "operands": [null
          ]
      },{
          "pc": "0x72",
          "operation": "push",
          "operands": ["%rbp"
          ]
      },{
  ...
      },{
          "pc": "0xde",
          "operation": "retq",
          "operands": [null
          ]
      }
  ]

After applying this patch:

  # echo 0 > /proc/sys/net/core/bpf_jit_kallsyms
  # bpftool prog dump jited id 1

  0xffffffffc02c7000:
     0:	push   %rbp
     1:	mov    %rsp,%rbp
  ...
    70:	leaveq
    71:	retq

  0xffffffffc02cf000:
     0:	push   %rbp
     1:	mov    %rsp,%rbp
  ...
    6b:	leaveq
    6c:	retq

  # bpftool -p prog dump jited id 1

  [{
          "name": "0xffffffffc02c7000",
          "insns": [{
                  "pc": "0x0",
                  "operation": "push",
                  "operands": ["%rbp"
                  ]
              },{
  ...
              },{
                  "pc": "0x71",
                  "operation": "retq",
                  "operands": [null
                  ]
              }
          ]
      },{
          "name": "0xffffffffc02cf000",
          "insns": [{
                  "pc": "0x0",
                  "operation": "push",
                  "operands": ["%rbp"
                  ]
              },{
  ...
              },{
                  "pc": "0x6c",
                  "operation": "retq",
                  "operands": [null
                  ]
              }
          ]
      }
  ]

  # echo 1 > /proc/sys/net/core/bpf_jit_kallsyms
  # bpftool prog dump jited id 1

  bpf_prog_b811aab41a39ad3d_foo:
     0:	push   %rbp
     1:	mov    %rsp,%rbp
  ...
    70:	leaveq
    71:	retq

  bpf_prog_cf418ac8b67bebd9_F:
     0:	push   %rbp
     1:	mov    %rsp,%rbp
  ...
    6b:	leaveq
    6c:	retq

  # bpftool -p prog dump jited id 1

  [{
          "name": "bpf_prog_b811aab41a39ad3d_foo",
          "insns": [{
                  "pc": "0x0",
                  "operation": "push",
                  "operands": ["%rbp"
                  ]
              },{
  ...
              },{
                  "pc": "0x71",
                  "operation": "retq",
                  "operands": [null
                  ]
              }
          ]
      },{
          "name": "bpf_prog_cf418ac8b67bebd9_F",
          "insns": [{
                  "pc": "0x0",
                  "operation": "push",
                  "operands": ["%rbp"
                  ]
              },{
  ...
              },{
                  "pc": "0x6c",
                  "operation": "retq",
                  "operands": [null
                  ]
              }
          ]
      }
  ]

Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-24 09:20:50 +02:00
..
bash-completion tools: bpftool: add simple perf event output reader 2018-05-04 23:41:04 +02:00
Documentation tools: bpftool: add simple perf event output reader 2018-05-04 23:41:04 +02:00
.gitignore selftests/bpf: ignore build products 2018-05-10 00:41:06 +02:00
cfg.c tools: bpftool: generate .dot graph from CFG information 2018-03-01 18:29:49 -08:00
cfg.h tools: bpftool: detect sub-programs from the eBPF sequence 2018-03-01 18:29:48 -08:00
cgroup.c bpftool: Support new prog types and attach types 2018-04-18 14:39:24 +02:00
common.c tools: bpftool: add simple perf event output reader 2018-05-04 23:41:04 +02:00
jit_disasm.c tools: bpftool: improve architecture detection by using ifindex 2018-01-18 01:26:15 +01:00
json_writer.c tools: bpftool: add JSON output for bpftool prog dump xlated * command 2017-10-24 01:25:08 +01:00
json_writer.h tools: bpftool: add JSON output for bpftool prog dump xlated * command 2017-10-24 01:25:08 +01:00
main.c tools: bpftool: add support for quotations in batch files 2018-03-02 09:46:41 +01:00
main.h tools: bpftool: add simple perf event output reader 2018-05-04 23:41:04 +02:00
Makefile tools: bpftool: add simple perf event output reader 2018-05-04 23:41:04 +02:00
map_perf_ring.c tools: bpf: move the event reading loop to libbpf 2018-05-11 01:40:52 +02:00
map.c bpf: bpftool, support for sockhash 2018-05-16 22:00:21 +02:00
prog.c tools: bpftool: add delimiters to multi-function JITed dumps 2018-05-24 09:20:50 +02:00
xlated_dumper.c tools: bpftool: add delimiters to multi-function JITed dumps 2018-05-24 09:20:50 +02:00
xlated_dumper.h tools: bpftool: add delimiters to multi-function JITed dumps 2018-05-24 09:20:50 +02:00