linux/tools/bpf/bpftool/struct_ops.c

648 lines
14 KiB

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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: Mount bpffs on provided dir instead of parent dir When pinning programs/objects under PATH (eg: during "bpftool prog loadall") the bpffs is mounted on the parent dir of PATH in the following situations: - the given dir exists but it is not bpffs. - the given dir doesn't exist and the parent dir is not bpffs. Mounting on the parent dir can also have the unintentional side- effect of hiding other files located under the parent dir. If the given dir exists but is not bpffs, then the bpffs should be mounted on the given dir and not its parent dir. Similarly, if the given dir doesn't exist and its parent dir is not bpffs, then the given dir should be created and the bpffs should be mounted on this new dir. Fixes: 2a36c26fe3b8 ("bpftool: Support bpffs mountpoint as pin path for prog loadall") Signed-off-by: Sahil Siddiq <icegambit91@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/2da44d24-74ae-a564-1764-afccf395eeec@isovalent.com/T/#t Link: https://lore.kernel.org/bpf/20240404192219.52373-1-icegambit91@gmail.com Closes: https://github.com/libbpf/bpftool/issues/100 Changes since v1: - Split "mount_bpffs_for_pin" into two functions. This is done to improve maintainability and readability. Changes since v2: - mount_bpffs_for_pin: rename to "create_and_mount_bpffs_dir". - mount_bpffs_given_file: rename to "mount_bpffs_given_file". - create_and_mount_bpffs_dir: - introduce "dir_exists" boolean. - remove new dir if "mnt_fs" fails. - improve error handling and error messages. Changes since v3: - Rectify function name. - Improve error messages and formatting. - mount_bpffs_for_file: - Check if dir exists before block_mount check. Changes since v4: - Use strdup instead of strcpy. - create_and_mount_bpffs_dir: - Use S_IRWXU instead of 0700. - Improve error handling and formatting.
2024-04-05 00:52:19 +05:30
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: 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
Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK" This reverts commit a777e18f1bcd32528ff5dfd10a6629b655b05eb8. In commit a777e18f1bcd ("bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"), we removed the rlimit bump in bpftool, because the kernel has switched to memcg-based memory accounting. Thanks to the LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK, we attempted to keep compatibility with other systems and ask libbpf to raise the limit for us if necessary. How do we know if memcg-based accounting is supported? There is a probe in libbpf to check this. But this probe currently relies on the availability of a given BPF helper, bpf_ktime_get_coarse_ns(), which landed in the same kernel version as the memory accounting change. This works in the generic case, but it may fail, for example, if the helper function has been backported to an older kernel. This has been observed for Google Cloud's Container-Optimized OS (COS), where the helper is available but rlimit is still in use. The probe succeeds, the rlimit is not raised, and probing features with bpftool, for example, fails. A patch was submitted [0] to update this probe in libbpf, based on what the cilium/ebpf Go library does [1]. It would lower the soft rlimit to 0, attempt to load a BPF object, and reset the rlimit. But it may induce some hard-to-debug flakiness if another process starts, or the current application is killed, while the rlimit is reduced, and the approach was discarded. As a workaround to ensure that the rlimit bump does not depend on the availability of a given helper, we restore the unconditional rlimit bump in bpftool for now. [0] https://lore.kernel.org/bpf/20220609143614.97837-1-quentin@isovalent.com/ [1] https://github.com/cilium/ebpf/blob/v0.9.0/rlimit/rlimit.go#L39 Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Yafang Shao <laoar.shao@gmail.com> Cc: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20220610112648.29695-2-quentin@isovalent.com
2022-06-10 12:26:47 +01:00
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: 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: 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: 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: 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: 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: 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: 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: 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