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2024-05-18bpftool: Introduce btf c dump sortingMykyta Yatsenko
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>
2024-04-16bpftool: Update documentation where progs/maps can be passed by nameQuentin Monnet
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
2024-04-02bpftool: Remove useless emphasis on command description in man pagesRameez Rehman
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
2024-04-02bpftool: Use simpler indentation in source rST for documentationRameez Rehman
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
2021-11-16bpftool: Update doc (use susbtitutions) and test_bpftool_synctypes.pyQuentin Monnet
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
2021-11-16bpftool: Add SPDX tags to RST documentation filesQuentin Monnet
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
2021-11-14bpftool: Fix indent in option lists in the documentationQuentin Monnet
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: c07ba629df97 ("tools: bpftool: Update and synchronise option list in doc and help msg") Fixes: 8cc8c6357c8f ("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
2021-07-30tools: bpftool: Document and add bash completion for -L, -B optionsQuentin Monnet
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: 75fa1777694c ("tools/bpftool: Add bpftool support for split BTF") Fixes: d510296d331a ("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
2021-07-30tools: bpftool: Update and synchronise option list in doc and help msgQuentin Monnet
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
2020-09-10tools: bpftool: Automate generation for "SEE ALSO" sections in man pagesQuentin Monnet
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
2020-09-10tools: bpftool: Include common options from separate fileQuentin Monnet
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
2020-09-10tools: bpftool: Log info-level messages when building bpftool man pagesQuentin Monnet
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
2020-06-22tools/bpftool: Add documentation and sample output for process infoAndrii Nakryiko
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
2020-05-11tools, bpftool: Minor fixes for documentationQuentin Monnet
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
2019-08-20tools: bpftool: implement "bpftool btf show|list"Quentin Monnet
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>
2019-05-28tools: bpftool: add -d option to get debug output from libbpfQuentin Monnet
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>
2019-05-24bpftool/docs: add description of btf dump C optionAndrii Nakryiko
Document optional **c** option for btf dump subcommand. Cc: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-25bpftool/docs: add btf sub-command documentationAndrii Nakryiko
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>