linux/tools/bpf/bpftool
Quentin Monnet 9fd496848b bpftool: Support inline annotations when dumping the CFG of a program
We support dumping the control flow graph of loaded programs to the DOT
format with bpftool, but so far this feature wouldn't display the source
code lines available through BTF along with the eBPF bytecode. Let's add
support for these annotations, to make it easier to read the graph.

In prog.c, we move the call to dump_xlated_cfg() in order to pass and
use the full struct dump_data, instead of creating a minimal one in
draw_bb_node().

We pass the pointer to this struct down to dump_xlated_for_graph() in
xlated_dumper.c, where most of the logics is added. We deal with BTF
mostly like we do for plain or JSON output, except that we cannot use a
"nr_skip" value to skip a given number of linfo records (we don't
process the BPF instructions linearly, and apart from the root of the
graph we don't know how many records we should skip, so we just store
the last linfo and make sure the new one we find is different before
printing it).

When printing the source instructions to the label of a DOT graph node,
there are a few subtleties to address. We want some special newline
markers, and there are some characters that we must escape. To deal with
them, we introduce a new dedicated function btf_dump_linfo_dotlabel() in
btf_dumper.c. We'll reuse this function in a later commit to format the
filepath, line, and column references as well.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-4-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
..
bash-completion bpftool: remove support of --legacy option for bpftool 2022-11-20 16:17:46 -08:00
Documentation bpftool: Fix documentation about line info display for prog dumps 2023-04-05 21:27:27 -07:00
skeleton bpftool: Add bpf_cookie to link output 2022-03-15 15:07:27 -07:00
.gitignore
btf.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
btf_dumper.c bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
cfg.c bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
cfg.h bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
cgroup.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
common.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
feature.c bpftool: fix output for skipping kernel config check 2023-01-10 17:42:31 -08:00
gen.c bpftool: clean-up usage of libbpf_get_error() 2022-11-20 16:17:46 -08:00
iter.c bpftool: clean-up usage of libbpf_get_error() 2022-11-20 16:17:46 -08:00
jit_disasm.c bpftool: Fix spelling mistake "disasembler" -> "disassembler" 2022-10-26 18:20:22 -07:00
json_writer.c tools: bpftool: json: Fix backslash escape typo in jsonw_puts 2023-03-29 09:48:45 -07:00
json_writer.h tools: bpftool: json: Fix backslash escape typo in jsonw_puts 2023-03-29 09:48:45 -07:00
link.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
main.c bpftool: clean-up usage of libbpf_get_error() 2022-11-20 16:17:46 -08:00
main.h bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
Makefile bpftool: Always disable stack protection for BPF objects 2023-01-13 16:44:21 +01:00
map.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
map_perf_ring.c bpftool: Fix error message of strerror 2022-09-30 15:40:46 -07:00
net.c bpftool: Define _GNU_SOURCE only once 2022-10-25 10:11:56 -07:00
netlink_dumper.c
netlink_dumper.h
perf.c bpftool: Define _GNU_SOURCE only once 2022-10-25 10:11:56 -07:00
pids.c libbpf: Hashmap interface update to allow both long and void* keys/values 2022-11-09 20:45:14 -08:00
prog.c bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
struct_ops.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
tracelog.c bpftool, musl compat: Replace sys/fcntl.h by fcntl.h 2022-04-25 23:24:28 +02:00
xlated_dumper.c bpftool: Support inline annotations when dumping the CFG of a program 2023-04-05 21:27:27 -07:00
xlated_dumper.h