linux/tools
Quentin Monnet 4567b983f7 tools: bpftool: add probes for kernel configuration options
Add probes to dump a number of options set (or not set) for compiling
the kernel image. These parameters provide information about what BPF
components should be available on the system. A number of them are not
directly related to eBPF, but are in fact used in the kernel as
conditions on which to compile, or not to compile, some of the eBPF
helper functions.

Sample output:

    # bpftool feature probe kernel
    Scanning system configuration...
    ...
    CONFIG_BPF is set to y
    CONFIG_BPF_SYSCALL is set to y
    CONFIG_HAVE_EBPF_JIT is set to y
    ...

    # bpftool --pretty --json feature probe kernel
    {
        "system_config": {
            ...
            "CONFIG_BPF": "y",
            "CONFIG_BPF_SYSCALL": "y",
            "CONFIG_HAVE_EBPF_JIT": "y",
            ...
        }
    }

v5:
- Declare options[] array in probe_kernel_image_config() as static.

v4:
- Add some options to the list:
    - CONFIG_TRACING
    - CONFIG_KPROBE_EVENTS
    - CONFIG_UPROBE_EVENTS
    - CONFIG_FTRACE_SYSCALLS
- Add comments about those options in the source code.

v3:
- Add a comment about /proc/config.gz not being supported as a path for
  the config file at this time.
- Use p_info() instead of p_err() on failure to get options from config
  file, as bpftool keeps probing other parameters and that would
  possibly create duplicate "error" entries for JSON.

v2:
- Remove C-style macros output from this patch.
- NOT addressed: grouping of those config options into subsections
  (I don't see an easy way of grouping them at the moment, please see
  also the discussion on v1 thread).

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
..
accounting delayacct: track delays from thrashing cache pages 2018-10-26 16:26:32 -07:00
arch Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-01-11 09:44:05 -08:00
bpf tools: bpftool: add probes for kernel configuration options 2019-01-22 22:15:40 -08:00
build perf build: Don't unconditionally link the libbfd feature test to -liberty and -lz 2018-12-21 09:42:46 -03:00
cgroup
crypto crypto: user - rename err_cnt parameter 2018-12-07 14:15:00 +08:00
firewire
firmware tools: Add 'firmware' category and add ihex2fw tool 2018-11-11 12:58:27 -08:00
gpio tools gpio: Allow overriding CFLAGS 2018-12-28 16:33:08 -03:00
hv Tools: hv: kvp: Fix a warning of buffer overflow with gcc 8.0.1 2018-11-11 12:58:27 -08:00
iio tools iio: Override CFLAGS assignments 2019-01-04 12:54:49 -03:00
include Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-01-11 09:44:05 -08:00
kvm/kvm_stat tools/kvm_stat: switch to python3 2018-11-27 12:53:44 +01:00
laptop
leds
lib libbpf: don't define CC and AR 2019-01-16 22:47:43 +01:00
memory-model tools/memory-model: Add more LKMM limitations 2018-10-02 10:28:04 +02:00
nfsd
objtool objtool: Fix segfault in .cold detection with -ffunction-sections 2018-11-20 18:59:00 +01:00
pci tools: PCI: Change pcitest compiling process 2018-10-03 11:19:52 +01:00
pcmcia
perf tools headers powerpc: Remove unistd.h 2019-01-10 10:42:08 -03:00
power perf/core improvements and fixes: 2019-01-03 14:05:16 +01:00
scripts
spi spi: spidev_test: Improve decoded text part of hex dump 2018-09-04 17:00:37 +01:00
testing tools/bpf: add bpffs pretty print test for int128 2019-01-16 22:53:44 +01:00
thermal/tmon tools thermal tmon: Use -O3 instead of -O1 if available 2019-01-04 12:54:49 -03:00
time
usb usbip: tools: fix atoi() on non-null terminated string 2018-10-18 19:44:39 +02:00
virtio virtio: fix test build after uio.h change 2018-12-19 18:23:49 -05:00
vm tools/vm/page_owner: use page_owner_sort in the use example 2019-01-08 17:15:11 -08:00
wmi
Makefile tools: Add 'firmware' category and add ihex2fw tool 2018-11-11 12:58:27 -08:00