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bpftool: Add SPDX tags to RST documentation files 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
2021-11-15 22:58:42 +00:00
.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
bpftool: Add struct_ops support This patch adds struct_ops support to the bpftool. To recap a bit on the recent bpf_struct_ops feature on the kernel side: It currently supports "struct tcp_congestion_ops" to be implemented in bpf. At a high level, bpf_struct_ops is struct_ops map populated with a number of bpf progs. bpf_struct_ops currently supports the "struct tcp_congestion_ops". However, the bpf_struct_ops design is generic enough that other kernel struct ops can be supported in the future. Although struct_ops is map+progs at a high lever, there are differences in details. For example, 1) After registering a struct_ops, the struct_ops is held by the kernel subsystem (e.g. tcp-cc). Thus, there is no need to pin a struct_ops map or its progs in order to keep them around. 2) To iterate all struct_ops in a system, it iterates all maps in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is the current usual filter. In the future, it may need to filter by other struct_ops specific properties. e.g. filter by tcp_congestion_ops or other kernel subsystem ops in the future. 3) struct_ops requires the running kernel having BTF info. That allows more flexibility in handling other kernel structs. e.g. it can always dump the latest bpf_map_info. 4) Also, "struct_ops" command is not intended to repeat all features already provided by "map" or "prog". For example, if there really is a need to pin the struct_ops map, the user can use the "map" cmd to do that. While the first attempt was to reuse parts from map/prog.c, it ended up not a lot to share. The only obvious item is the map_parse_fds() but that still requires modifications to accommodate struct_ops map specific filtering (for the immediate and the future needs). Together with the earlier mentioned differences, it is better to part away from map/prog.c. The initial set of subcmds are, register, unregister, show, and dump. For register, it registers all struct_ops maps that can be found in an obj file. Option can be added in the future to specify a particular struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g. bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not implemented in this patch and it can be considered later also. For other subcmds, please see the man doc for details. A sample output of dump: [root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic [{ "bpf_map_info": { "type": 26, "id": 64, "key_size": 4, "value_size": 256, "max_entries": 1, "map_flags": 0, "name": "cubic", "ifindex": 0, "btf_vmlinux_value_type_id": 18452, "netns_dev": 0, "netns_ino": 0, "btf_id": 52, "btf_key_type_id": 0, "btf_value_type_id": 0 } },{ "bpf_struct_ops_tcp_congestion_ops": { "refcnt": { "refs": { "counter": 1 } }, "state": "BPF_STRUCT_OPS_STATE_INUSE", "data": { "list": { "next": 0, "prev": 0 }, "key": 0, "flags": 0, "init": "void (struct sock *) bictcp_init/prog_id:138", "release": "void (struct sock *) 0", "ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141", "cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140", "set_state": "void (struct sock *, u8) bictcp_state/prog_id:142", "cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139", "in_ack_event": "void (struct sock *, u32) 0", "undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144", "pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143", "min_tso_segs": "u32 (struct sock *) 0", "sndbuf_expand": "u32 (struct sock *) 0", "cong_control": "void (struct sock *, const struct rate_sample *) 0", "get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0", "name": "bpf_cubic", "owner": 0 } } } ] Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
2020-03-18 10:16:56 -07:00
==================
bpftool-struct_ops
==================
-------------------------------------------------------------------------------
tool to register/unregister/introspect BPF struct_ops
-------------------------------------------------------------------------------
:Manual section: 8
bpftool: Update doc (use susbtitutions) and test_bpftool_synctypes.py 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
2021-11-15 22:58:43 +00:00
.. include:: substitutions.rst
bpftool: Add struct_ops support This patch adds struct_ops support to the bpftool. To recap a bit on the recent bpf_struct_ops feature on the kernel side: It currently supports "struct tcp_congestion_ops" to be implemented in bpf. At a high level, bpf_struct_ops is struct_ops map populated with a number of bpf progs. bpf_struct_ops currently supports the "struct tcp_congestion_ops". However, the bpf_struct_ops design is generic enough that other kernel struct ops can be supported in the future. Although struct_ops is map+progs at a high lever, there are differences in details. For example, 1) After registering a struct_ops, the struct_ops is held by the kernel subsystem (e.g. tcp-cc). Thus, there is no need to pin a struct_ops map or its progs in order to keep them around. 2) To iterate all struct_ops in a system, it iterates all maps in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is the current usual filter. In the future, it may need to filter by other struct_ops specific properties. e.g. filter by tcp_congestion_ops or other kernel subsystem ops in the future. 3) struct_ops requires the running kernel having BTF info. That allows more flexibility in handling other kernel structs. e.g. it can always dump the latest bpf_map_info. 4) Also, "struct_ops" command is not intended to repeat all features already provided by "map" or "prog". For example, if there really is a need to pin the struct_ops map, the user can use the "map" cmd to do that. While the first attempt was to reuse parts from map/prog.c, it ended up not a lot to share. The only obvious item is the map_parse_fds() but that still requires modifications to accommodate struct_ops map specific filtering (for the immediate and the future needs). Together with the earlier mentioned differences, it is better to part away from map/prog.c. The initial set of subcmds are, register, unregister, show, and dump. For register, it registers all struct_ops maps that can be found in an obj file. Option can be added in the future to specify a particular struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g. bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not implemented in this patch and it can be considered later also. For other subcmds, please see the man doc for details. A sample output of dump: [root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic [{ "bpf_map_info": { "type": 26, "id": 64, "key_size": 4, "value_size": 256, "max_entries": 1, "map_flags": 0, "name": "cubic", "ifindex": 0, "btf_vmlinux_value_type_id": 18452, "netns_dev": 0, "netns_ino": 0, "btf_id": 52, "btf_key_type_id": 0, "btf_value_type_id": 0 } },{ "bpf_struct_ops_tcp_congestion_ops": { "refcnt": { "refs": { "counter": 1 } }, "state": "BPF_STRUCT_OPS_STATE_INUSE", "data": { "list": { "next": 0, "prev": 0 }, "key": 0, "flags": 0, "init": "void (struct sock *) bictcp_init/prog_id:138", "release": "void (struct sock *) 0", "ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141", "cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140", "set_state": "void (struct sock *, u8) bictcp_state/prog_id:142", "cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139", "in_ack_event": "void (struct sock *, u32) 0", "undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144", "pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143", "min_tso_segs": "u32 (struct sock *) 0", "sndbuf_expand": "u32 (struct sock *) 0", "cong_control": "void (struct sock *, const struct rate_sample *) 0", "get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0", "name": "bpf_cubic", "owner": 0 } } } ] Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
2020-03-18 10:16:56 -07:00
SYNOPSIS
========
**bpftool** [*OPTIONS*] **struct_ops** *COMMAND*
bpftool: Update doc (use susbtitutions) and test_bpftool_synctypes.py 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
2021-11-15 22:58:43 +00:00
*OPTIONS* := { |COMMON_OPTIONS| }
bpftool: Add struct_ops support This patch adds struct_ops support to the bpftool. To recap a bit on the recent bpf_struct_ops feature on the kernel side: It currently supports "struct tcp_congestion_ops" to be implemented in bpf. At a high level, bpf_struct_ops is struct_ops map populated with a number of bpf progs. bpf_struct_ops currently supports the "struct tcp_congestion_ops". However, the bpf_struct_ops design is generic enough that other kernel struct ops can be supported in the future. Although struct_ops is map+progs at a high lever, there are differences in details. For example, 1) After registering a struct_ops, the struct_ops is held by the kernel subsystem (e.g. tcp-cc). Thus, there is no need to pin a struct_ops map or its progs in order to keep them around. 2) To iterate all struct_ops in a system, it iterates all maps in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is the current usual filter. In the future, it may need to filter by other struct_ops specific properties. e.g. filter by tcp_congestion_ops or other kernel subsystem ops in the future. 3) struct_ops requires the running kernel having BTF info. That allows more flexibility in handling other kernel structs. e.g. it can always dump the latest bpf_map_info. 4) Also, "struct_ops" command is not intended to repeat all features already provided by "map" or "prog". For example, if there really is a need to pin the struct_ops map, the user can use the "map" cmd to do that. While the first attempt was to reuse parts from map/prog.c, it ended up not a lot to share. The only obvious item is the map_parse_fds() but that still requires modifications to accommodate struct_ops map specific filtering (for the immediate and the future needs). Together with the earlier mentioned differences, it is better to part away from map/prog.c. The initial set of subcmds are, register, unregister, show, and dump. For register, it registers all struct_ops maps that can be found in an obj file. Option can be added in the future to specify a particular struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g. bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not implemented in this patch and it can be considered later also. For other subcmds, please see the man doc for details. A sample output of dump: [root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic [{ "bpf_map_info": { "type": 26, "id": 64, "key_size": 4, "value_size": 256, "max_entries": 1, "map_flags": 0, "name": "cubic", "ifindex": 0, "btf_vmlinux_value_type_id": 18452, "netns_dev": 0, "netns_ino": 0, "btf_id": 52, "btf_key_type_id": 0, "btf_value_type_id": 0 } },{ "bpf_struct_ops_tcp_congestion_ops": { "refcnt": { "refs": { "counter": 1 } }, "state": "BPF_STRUCT_OPS_STATE_INUSE", "data": { "list": { "next": 0, "prev": 0 }, "key": 0, "flags": 0, "init": "void (struct sock *) bictcp_init/prog_id:138", "release": "void (struct sock *) 0", "ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141", "cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140", "set_state": "void (struct sock *, u8) bictcp_state/prog_id:142", "cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139", "in_ack_event": "void (struct sock *, u32) 0", "undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144", "pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143", "min_tso_segs": "u32 (struct sock *) 0", "sndbuf_expand": "u32 (struct sock *) 0", "cong_control": "void (struct sock *, const struct rate_sample *) 0", "get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0", "name": "bpf_cubic", "owner": 0 } } } ] Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
2020-03-18 10:16:56 -07:00
*COMMANDS* :=
{ **show** | **list** | **dump** | **register** | **unregister** | **help** }
STRUCT_OPS COMMANDS
===================
| **bpftool** **struct_ops { show | list }** [*STRUCT_OPS_MAP*]
| **bpftool** **struct_ops dump** [*STRUCT_OPS_MAP*]
| **bpftool** **struct_ops register** *OBJ*
| **bpftool** **struct_ops unregister** *STRUCT_OPS_MAP*
| **bpftool** **struct_ops help**
|
| *STRUCT_OPS_MAP* := { **id** *STRUCT_OPS_MAP_ID* | **name** *STRUCT_OPS_MAP_NAME* }
| *OBJ* := /a/file/of/bpf_struct_ops.o
DESCRIPTION
===========
**bpftool struct_ops { show | list }** [*STRUCT_OPS_MAP*]
Show brief information about the struct_ops in the system.
If *STRUCT_OPS_MAP* is specified, it shows information only
for the given struct_ops. Otherwise, it lists all struct_ops
currently existing in the system.
Output will start with struct_ops map ID, followed by its map
name and its struct_ops's kernel type.
**bpftool struct_ops dump** [*STRUCT_OPS_MAP*]
Dump details information about the struct_ops in the system.
If *STRUCT_OPS_MAP* is specified, it dumps information only
for the given struct_ops. Otherwise, it dumps all struct_ops
currently existing in the system.
**bpftool struct_ops register** *OBJ*
Register bpf struct_ops from *OBJ*. All struct_ops under
the ELF section ".struct_ops" will be registered to
its kernel subsystem.
**bpftool struct_ops unregister** *STRUCT_OPS_MAP*
Unregister the *STRUCT_OPS_MAP* from the kernel subsystem.
**bpftool struct_ops help**
Print short help message.
OPTIONS
=======
tools: bpftool: Include common options from separate file 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
2020-09-09 17:24:59 +01:00
.. include:: common_options.rst
bpftool: Add struct_ops support This patch adds struct_ops support to the bpftool. To recap a bit on the recent bpf_struct_ops feature on the kernel side: It currently supports "struct tcp_congestion_ops" to be implemented in bpf. At a high level, bpf_struct_ops is struct_ops map populated with a number of bpf progs. bpf_struct_ops currently supports the "struct tcp_congestion_ops". However, the bpf_struct_ops design is generic enough that other kernel struct ops can be supported in the future. Although struct_ops is map+progs at a high lever, there are differences in details. For example, 1) After registering a struct_ops, the struct_ops is held by the kernel subsystem (e.g. tcp-cc). Thus, there is no need to pin a struct_ops map or its progs in order to keep them around. 2) To iterate all struct_ops in a system, it iterates all maps in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is the current usual filter. In the future, it may need to filter by other struct_ops specific properties. e.g. filter by tcp_congestion_ops or other kernel subsystem ops in the future. 3) struct_ops requires the running kernel having BTF info. That allows more flexibility in handling other kernel structs. e.g. it can always dump the latest bpf_map_info. 4) Also, "struct_ops" command is not intended to repeat all features already provided by "map" or "prog". For example, if there really is a need to pin the struct_ops map, the user can use the "map" cmd to do that. While the first attempt was to reuse parts from map/prog.c, it ended up not a lot to share. The only obvious item is the map_parse_fds() but that still requires modifications to accommodate struct_ops map specific filtering (for the immediate and the future needs). Together with the earlier mentioned differences, it is better to part away from map/prog.c. The initial set of subcmds are, register, unregister, show, and dump. For register, it registers all struct_ops maps that can be found in an obj file. Option can be added in the future to specify a particular struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g. bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not implemented in this patch and it can be considered later also. For other subcmds, please see the man doc for details. A sample output of dump: [root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic [{ "bpf_map_info": { "type": 26, "id": 64, "key_size": 4, "value_size": 256, "max_entries": 1, "map_flags": 0, "name": "cubic", "ifindex": 0, "btf_vmlinux_value_type_id": 18452, "netns_dev": 0, "netns_ino": 0, "btf_id": 52, "btf_key_type_id": 0, "btf_value_type_id": 0 } },{ "bpf_struct_ops_tcp_congestion_ops": { "refcnt": { "refs": { "counter": 1 } }, "state": "BPF_STRUCT_OPS_STATE_INUSE", "data": { "list": { "next": 0, "prev": 0 }, "key": 0, "flags": 0, "init": "void (struct sock *) bictcp_init/prog_id:138", "release": "void (struct sock *) 0", "ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141", "cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140", "set_state": "void (struct sock *, u8) bictcp_state/prog_id:142", "cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139", "in_ack_event": "void (struct sock *, u32) 0", "undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144", "pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143", "min_tso_segs": "u32 (struct sock *) 0", "sndbuf_expand": "u32 (struct sock *) 0", "cong_control": "void (struct sock *, const struct rate_sample *) 0", "get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0", "name": "bpf_cubic", "owner": 0 } } } ] Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
2020-03-18 10:16:56 -07:00
EXAMPLES
========
**# bpftool struct_ops show**
::
100: dctcp tcp_congestion_ops
105: cubic tcp_congestion_ops
**# bpftool struct_ops unregister id 105**
::
Unregistered tcp_congestion_ops cubic id 105
**# bpftool struct_ops register bpf_cubic.o**
::
Registered tcp_congestion_ops cubic id 110
Reference in a new issue Copy permalink