linux/tools/lib
Quentin Monnet 2d3ea5e85d tools: bpftool: add probes for eBPF helper functions
Similarly to what was done for program types and map types, add a set of
probes to test the availability of the different eBPF helper functions
on the current system.

For each known program type, all known helpers are tested, in order to
establish a compatibility matrix. Output is provided as a set of lists
of available helpers, one per program type.

Sample output:

    # bpftool feature probe kernel
    ...
    Scanning eBPF helper functions...
    eBPF helpers supported for program type socket_filter:
            - bpf_map_lookup_elem
            - bpf_map_update_elem
            - bpf_map_delete_elem
    ...
    eBPF helpers supported for program type kprobe:
            - bpf_map_lookup_elem
            - bpf_map_update_elem
            - bpf_map_delete_elem
    ...

    # bpftool --json --pretty feature probe kernel
    {
        ...
        "helpers": {
            "socket_filter_available_helpers": ["bpf_map_lookup_elem", \
                    "bpf_map_update_elem","bpf_map_delete_elem", ...
            ],
            "kprobe_available_helpers": ["bpf_map_lookup_elem", \
                    "bpf_map_update_elem","bpf_map_delete_elem", ...
            ],
            ...
        }
    }

v5:
- In libbpf.map, move global symbol to the new LIBBPF_0.0.2 section.

v4:
- Use "enum bpf_func_id" instead of "__u32" in bpf_probe_helper()
  declaration for the type of the argument used to pass the id of
  the helper to probe.
- Undef BPF_HELPER_MAKE_ENTRY after using it.

v3:
- Do not pass kernel version from bpftool to libbpf probes (kernel
  version for testing program with kprobes is retrieved directly from
  libbpf).
- Dump one list of available helpers per program type (instead of one
  list of compatible program types per helper).

v2:
- Move probes from bpftool to libbpf.
- Test all program types for each helper, print a list of working prog
  types for each helper.
- Fall back on include/uapi/linux/bpf.h for names and ids of helpers.
- Remove C-style macros output from this patch.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-22 22:15:40 -08:00
..
api perf tools: Fix tracing_path_mount proper path 2018-10-16 12:27:46 -03:00
bpf tools: bpftool: add probes for eBPF helper functions 2019-01-22 22:15:40 -08:00
lockdep tools/lib/lockdep/tests: Test the lockdep_reset_lock() implementation 2018-12-11 14:54:51 +01:00
subcmd tools lib subcmd: Don't add the kernel sources to the include path 2018-12-18 12:23:56 -03:00
symbol tools lib symbols: Introduce kallsyms__is_function() 2018-04-26 13:47:14 -03:00
traceevent tools lib traceevent: Remove tep_data_event_from_type() API 2019-01-08 13:28:13 -03:00
bitmap.c tools lib: Add bitmap_and function 2016-08-02 16:33:27 -03:00
find_bit.c lib: optimize cpumask_next_and() 2018-02-06 18:32:44 -08:00
hweight.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rbtree.c tools: Copy lib/rbtree.c to tools/lib/ 2015-07-05 22:48:21 -03:00
str_error_r.c objtool, perf: Fix GCC 8 -Wrestrict error 2018-03-19 13:51:54 -03:00
string.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vsprintf.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00