Some projects, for example xdp-tools [0], prefer to check in a minimized
vmlinux.h rather than the complete file which can get rather large.
However, when you try to add a minimized version of a complex struct (eg
struct xfrm_state), things can get quite complex if you're trying to
manually untangle and deduplicate the dependencies.
This commit teaches bpftool to do a minimized dump of a specific types by
providing a optional root_id argument(s).
Example usage:
$ ./bpftool btf dump file ~/dev/linux/vmlinux | rg "STRUCT 'xfrm_state'"
[12643] STRUCT 'xfrm_state' size=912 vlen=58
$ ./bpftool btf dump file ~/dev/linux/vmlinux root_id 12643 format c
#ifndef __VMLINUX_H__
#define __VMLINUX_H__
[..]
struct xfrm_type_offload;
struct xfrm_sec_ctx;
struct xfrm_state {
possible_net_t xs_net;
union {
struct hlist_node gclist;
struct hlist_node bydst;
};
union {
struct hlist_node dev_gclist;
struct hlist_node bysrc;
};
struct hlist_node byspi;
[..]
[0]: https://github.com/xdp-project/xdp-tools/blob/master/headers/bpf/vmlinux.h
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/04feb860c0a56a7da66f923551484e1483a72074.1734119028.git.dxu@dxuuu.xyz
Sort bpftool c dump output; aiming to simplify vmlinux.h diffing and
forcing more natural type definitions ordering.
Definitions are sorted first by their BTF kind ranks, then by their base
type name and by their own name.
Type ranks
Assign ranks to btf kinds (defined in function btf_type_rank) to set
next order:
1. Anonymous enums/enums64
2. Named enums/enums64
3. Trivial types typedefs (ints, then floats)
4. Structs/Unions
5. Function prototypes
6. Forward declarations
Type rank is set to maximum for unnamed reference types, structs and
unions to avoid emitting those types early. They will be emitted as
part of the type chain starting with named type.
Lexicographical ordering
Each type is assigned a sort_name and own_name.
sort_name is the resolved name of the final base type for reference
types (typedef, pointer, array etc). Sorting by sort_name allows to
group typedefs of the same base type. sort_name for non-reference type
is the same as own_name. own_name is a direct name of particular type,
is used as final sorting step.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240514131221.20585-1-yatsenko@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When using references to BPF programs, bpftool supports passing programs
by name on the command line. The manual pages for "bpftool prog" and
"bpftool map" (for prog_array updates) mention it, but we have a few
additional subcommands that support referencing programs by name but do
not mention it in their documentation. Let's update the pages for
subcommands "btf", "cgroup", and "net".
Similarly, we can reference maps by name when passing them to "bpftool
prog load", so we update the page for "bpftool prog" as well.
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240413011427.14402-2-qmo@kernel.org
As it turns out, the terms in definition lists in the rST file are
already rendered with bold-ish formatting when generating the man pages;
all double-star sequences we have in the commands for the command
description are unnecessary, and can be removed to make the
documentation easier to read.
The rST files were automatically processed with:
sed -i '/DESCRIPTION/,/OPTIONS/ { /^\*/ s/\*\*//g }' b*.rst
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-3-qmo@kernel.org
The rST manual pages for bpftool would use a mix of tabs and spaces for
indentation. While this is the norm in C code, this is rather unusual
for rST documents, and over time we've seen many contributors use a
wrong level of indentation for documentation update.
Let's fix bpftool's indentation in docs once and for all:
- Let's use spaces, that are more common in rST files.
- Remove one level of indentation for the synopsis, the command
description, and the "see also" section. As a result, all sections
start with the same indentation level in the generated man page.
- Rewrap the paragraphs after the changes.
There is no content change in this patch, only indentation and
rewrapping changes. The wrapping in the generated source files for the
manual pages is changed, but the pages displayed with "man" remain the
same, apart from the adjusted indentation level on relevant sections.
[ Quentin: rebased on bpf-next, removed indent level for command
description and options, updated synopsis, command summary, and "see
also" sections. ]
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-2-qmo@kernel.org
test_bpftool_synctypes.py helps detecting inconsistencies in bpftool
between the different list of types and options scattered in the
sources, the documentation, and the bash completion. For options that
apply to all bpftool commands, the script had a hardcoded list of
values, and would use them to check whether the man pages are
up-to-date. When writing the script, it felt acceptable to have this
list in order to avoid to open and parse bpftool's main.h every time,
and because the list of global options in bpftool doesn't change so
often.
However, this is prone to omissions, and we recently added a new
-l|--legacy option which was described in common_options.rst, but not
listed in the options summary of each manual page. The script did not
complain, because it keeps comparing the hardcoded list to the (now)
outdated list in the header file.
To address the issue, this commit brings the following changes:
- Options that are common to all bpftool commands (--json, --pretty, and
--debug) are moved to a dedicated file, and used in the definition of
a RST substitution. This substitution is used in the sources of all
the man pages.
- This list of common options is updated, with the addition of the new
-l|--legacy option.
- The script test_bpftool_synctypes.py is updated to compare:
- Options specific to a command, found in C files, for the
interactive help messages, with the same specific options from the
relevant man page for that command.
- Common options, checked just once: the list in main.h is
compared with the new list in substitutions.rst.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-3-quentin@isovalent.com
Most files in the kernel repository have a SPDX tags. The files that
don't have such a tag (or another license boilerplate) tend to fall
under the GPL-2.0 license. In the past, bpftool's Makefile (for example)
has been marked as GPL-2.0 for that reason, when in fact all bpftool is
dual-licensed.
To prevent a similar confusion from happening with the RST documentation
files for bpftool, let's explicitly mark all files as dual-licensed.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-2-quentin@isovalent.com
Mixed indentation levels in the lists of options in bpftool's
documentation produces some unexpected results. For the "bpftool" man
page, it prints a warning:
$ make -C bpftool.8
GEN bpftool.8
<stdin>:26: (ERROR/3) Unexpected indentation.
For other pages, there is no warning, but it results in a line break
appearing in the option lists in the generated man pages.
RST paragraphs should have a uniform indentation level. Let's fix it.
Fixes: c07ba629df ("tools: bpftool: Update and synchronise option list in doc and help msg")
Fixes: 8cc8c6357c ("tools: bpftool: Document and add bash completion for -L, -B options")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211110114632.24537-5-quentin@isovalent.com
The -L|--use-loader option for using loader programs when loading, or
when generating a skeleton, did not have any documentation or bash
completion. Same thing goes for -B|--base-btf, used to pass a path to a
base BTF object for split BTF such as BTF for kernel modules.
This patch documents and adds bash completion for those options.
Fixes: 75fa177769 ("tools/bpftool: Add bpftool support for split BTF")
Fixes: d510296d33 ("bpftool: Use syscall/loader program in "prog load" and "gen skeleton" command.")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210730215435.7095-7-quentin@isovalent.com
All bpftool commands support the options for JSON output and debug from
libbpf. In addition, some commands support additional options
corresponding to specific use cases.
The list of options described in the man pages for the different
commands are not always accurate. The messages for interactive help are
mostly limited to HELP_SPEC_OPTIONS, and are even less representative of
the actual set of options supported for the commands.
Let's update the lists:
- HELP_SPEC_OPTIONS is modified to contain the "default" options (JSON
and debug), and to be extensible (no ending curly bracket).
- All commands use HELP_SPEC_OPTIONS in their help message, and then
complete the list with their specific options.
- The lists of options in the man pages are updated.
- The formatting of the list for bpftool.rst is adjusted to match
formatting for the other man pages. This is for consistency, and also
because it will be helpful in a future patch to automatically check
that the files are synchronised.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210730215435.7095-5-quentin@isovalent.com
The "SEE ALSO" sections of bpftool's manual pages refer to bpf(2),
bpf-helpers(7), then all existing bpftool man pages (save the current
one).
This leads to nearly-identical lists being duplicated in all manual
pages. Ideally, when a new page is created, all lists should be updated
accordingly, but this has led to omissions and inconsistencies multiple
times in the past.
Let's take it out of the RST files and generate the "SEE ALSO" sections
automatically in the Makefile when generating the man pages. The lists
are not really useful in the RST anyway because all other pages are
available in the same directory.
v3:
- Fix conflict with a previous patchset that introduced RST2MAN_OPTS
variable passed to rst2man.
v2:
- Use "echo -n" instead of "printf" in Makefile, to avoid any risk of
passing a format string directly to the command.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200910203935.25304-1-quentin@isovalent.com
Nearly all man pages for bpftool have the same common set of option
flags (--help, --version, --json, --pretty, --debug). The description is
duplicated across all the pages, which is more difficult to maintain if
the description of an option changes. It may also be confusing to sort
out what options are not "common" and should not be copied when creating
new manual pages.
Let's move the description for those common options to a separate file,
which is included with a RST directive when generating the man pages.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909162500.17010-3-quentin@isovalent.com
To build man pages for bpftool (and for eBPF helper functions), rst2man
can log different levels of information. Let's make it log all levels
to keep the RST files clean.
Doing so, rst2man complains about double colons, used for literal
blocks, that look like underlines for section titles. Let's add the
necessary blank lines.
v2:
- Use "--verbose" instead of "-r 1" (same behaviour but more readable).
- Pass it through a RST2MAN_OPTS variable so we can easily pass other
options too.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909162251.15498-2-quentin@isovalent.com
Add statements about bpftool being able to discover process info, holding
reference to BPF map, prog, link, or BTF. Show example output as well.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-10-andriin@fb.com
Bring minor improvements to bpftool documentation. Fix or harmonise
formatting, update map types (including in interactive help), improve
description for "map create", fix a build warning due to a missing line
after the double-colon for the "bpftool prog profile" example,
complete/harmonise/sort the list of related bpftool man pages in
footers.
v2:
- Remove (instead of changing) mark-up on "value" in bpftool-map.rst,
when it does not refer to something passed on the command line.
- Fix an additional typo ("hexadeximal") in the same file.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200511161536.29853-3-quentin@isovalent.com
Add a "btf list" (alias: "btf show") subcommand to bpftool in order to
dump all BTF objects loaded on a system.
When running the command, hash tables are built in bpftool to retrieve
all the associations between BTF objects and BPF maps and programs. This
allows for printing all such associations when listing the BTF objects.
The command is added at the top of the subcommands for "bpftool btf", so
that typing only "bpftool btf" also comes down to listing the programs.
We could not have this with the previous command ("dump"), which
required a BTF object id, so it should not break any previous behaviour.
This also makes the "btf" command behaviour consistent with "prog" or
"map".
Bash completion is updated to use "bpftool btf" instead of "bpftool
prog" to list the BTF ids, as it looks more consistent.
Example output (plain):
# bpftool btf show
9: size 2989B prog_ids 21 map_ids 15
17: size 2847B prog_ids 36 map_ids 30,29,28
26: size 2847B
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
libbpf has three levels of priority for output messages: warn, info,
debug. By default, debug output is not printed to the console.
Add a new "--debug" (short name: "-d") option to bpftool to print libbpf
logs for all three levels.
Internally, we simply use the function provided by libbpf to replace the
default printing function by one that prints logs regardless of their
level.
v2:
- Remove the possibility to select the log-levels to use (v1 offered a
combination of "warn", "info" and "debug").
- Rename option and offer a short name: -d|--debug.
- Add option description to all bpftool manual pages (instead of
bpftool-prog.rst only), as all commands use libbpf.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Document usage and sample output format for `btf dump` sub-command.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
