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Diffstat (limited to 'tools/bpf/bpftool/Documentation')
| -rw-r--r-- | tools/bpf/bpftool/Documentation/Makefile | 60 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-btf.rst | 268 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-cgroup.rst | 157 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-feature.rst | 90 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-gen.rst | 446 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-iter.rst | 76 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-link.rst | 112 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-map.rst | 277 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-net.rst | 182 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-perf.rst | 69 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-prog.rst | 375 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst | 92 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool.rst | 70 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/common_options.rst | 25 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/substitutions.rst | 3 |
15 files changed, 2302 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/Documentation/Makefile b/tools/bpf/bpftool/Documentation/Makefile new file mode 100644 index 000000000..ac8487dcf --- /dev/null +++ b/tools/bpf/bpftool/Documentation/Makefile @@ -0,0 +1,60 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +include ../../../scripts/Makefile.include + +INSTALL ?= install +RM ?= rm -f +RMDIR ?= rmdir --ignore-fail-on-non-empty + +ifeq ($(V),1) + Q = +else + Q = @ +endif + +prefix ?= /usr/local +mandir ?= $(prefix)/man +man8dir = $(mandir)/man8 + +MAN8_RST = $(wildcard bpftool*.rst) + +_DOC_MAN8 = $(patsubst %.rst,%.8,$(MAN8_RST)) +DOC_MAN8 = $(addprefix $(OUTPUT),$(_DOC_MAN8)) + +man: man8 +man8: $(DOC_MAN8) + +RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null) +RST2MAN_OPTS += --verbose --strip-comments + +list_pages = $(sort $(basename $(filter-out $(1),$(MAN8_RST)))) +see_also = $(subst " ",, \ + "\n" \ + "SEE ALSO\n" \ + "========\n" \ + "\t**bpf**\ (2),\n" \ + "\t**bpf-helpers**\\ (7)" \ + $(foreach page,$(call list_pages,$(1)),",\n\t**$(page)**\\ (8)") \ + "\n") + +$(OUTPUT)%.8: %.rst +ifndef RST2MAN_DEP + $(error "rst2man not found, but required to generate man pages") +endif + $(QUIET_GEN)( cat $< ; printf "%b" $(call see_also,$<) ) | rst2man $(RST2MAN_OPTS) > $@ + +clean: + $(call QUIET_CLEAN, Documentation) + $(Q)$(RM) $(DOC_MAN8) + +install: man + $(call QUIET_INSTALL, Documentation-man) + $(Q)$(INSTALL) -d -m 755 $(DESTDIR)$(man8dir) + $(Q)$(INSTALL) -m 644 $(DOC_MAN8) $(DESTDIR)$(man8dir) + +uninstall: + $(call QUIET_UNINST, Documentation-man) + $(Q)$(RM) $(addprefix $(DESTDIR)$(man8dir)/,$(_DOC_MAN8)) + $(Q)$(RMDIR) $(DESTDIR)$(man8dir) + +.PHONY: man man8 clean install uninstall +.DEFAULT_GOAL := man diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst new file mode 100644 index 000000000..342716f74 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst @@ -0,0 +1,268 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-btf +================ +------------------------------------------------------------------------------- +tool for inspection of BTF data +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **btf** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | { **-B** | **--base-btf** } } + + *COMMANDS* := { **dump** | **help** } + +BTF COMMANDS +============= + +| **bpftool** **btf** { **show** | **list** } [**id** *BTF_ID*] +| **bpftool** **btf dump** *BTF_SRC* [**format** *FORMAT*] +| **bpftool** **btf help** +| +| *BTF_SRC* := { **id** *BTF_ID* | **prog** *PROG* | **map** *MAP* [{**key** | **value** | **kv** | **all**}] | **file** *FILE* } +| *FORMAT* := { **raw** | **c** } +| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } + +DESCRIPTION +=========== + **bpftool btf { show | list }** [**id** *BTF_ID*] + Show information about loaded BTF objects. If a BTF ID is + specified, show information only about given BTF object, + otherwise list all BTF objects currently loaded on the + system. + + Since Linux 5.8 bpftool is able to discover information about + processes that hold open file descriptors (FDs) against BTF + objects. On such kernels bpftool will automatically emit this + information as well. + + **bpftool btf dump** *BTF_SRC* + Dump BTF entries from a given *BTF_SRC*. + + When **id** is specified, BTF object with that ID will be + loaded and all its BTF types emitted. + + When **map** is provided, it's expected that map has + associated BTF object with BTF types describing key and + value. It's possible to select whether to dump only BTF + type(s) associated with key (**key**), value (**value**), + both key and value (**kv**), or all BTF types present in + associated BTF object (**all**). If not specified, **kv** + is assumed. + + When **prog** is provided, it's expected that program has + associated BTF object with BTF types. + + When specifying *FILE*, an ELF file is expected, containing + .BTF section with well-defined BTF binary format data, + typically produced by clang or pahole. + + **format** option can be used to override default (raw) + output format. Raw (**raw**) or C-syntax (**c**) output + formats are supported. + + **bpftool btf help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -B, --base-btf *FILE* + Pass a base BTF object. Base BTF objects are typically used + with BTF objects for kernel modules. To avoid duplicating + all kernel symbols required by modules, BTF objects for + modules are "split", they are built incrementally on top of + the kernel (vmlinux) BTF object. So the base BTF reference + should usually point to the kernel BTF. + + When the main BTF object to process (for example, the + module BTF to dump) is passed as a *FILE*, bpftool attempts + to autodetect the path for the base object, and passing + this option is optional. When the main BTF object is passed + through other handles, this option becomes necessary. + +EXAMPLES +======== +**# bpftool btf dump id 1226** + +:: + + [1] PTR '(anon)' type_id=2 + [2] STRUCT 'dummy_tracepoint_args' size=16 vlen=2 + 'pad' type_id=3 bits_offset=0 + 'sock' type_id=4 bits_offset=64 + [3] INT 'long long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) + [4] PTR '(anon)' type_id=5 + [5] FWD 'sock' fwd_kind=union + +This gives an example of default output for all supported BTF kinds. + +**$ cat prog.c** + +:: + + struct fwd_struct; + + enum my_enum { + VAL1 = 3, + VAL2 = 7, + }; + + typedef struct my_struct my_struct_t; + + struct my_struct { + const unsigned int const_int_field; + int bitfield_field: 4; + char arr_field[16]; + const struct fwd_struct *restrict fwd_field; + enum my_enum enum_field; + volatile my_struct_t *typedef_ptr_field; + }; + + union my_union { + int a; + struct my_struct b; + }; + + struct my_struct struct_global_var __attribute__((section("data_sec"))) = { + .bitfield_field = 3, + .enum_field = VAL1, + }; + int global_var __attribute__((section("data_sec"))) = 7; + + __attribute__((noinline)) + int my_func(union my_union *arg1, int arg2) + { + static int static_var __attribute__((section("data_sec"))) = 123; + static_var++; + return static_var; + } + +**$ bpftool btf dump file prog.o** + +:: + + [1] PTR '(anon)' type_id=2 + [2] UNION 'my_union' size=48 vlen=2 + 'a' type_id=3 bits_offset=0 + 'b' type_id=4 bits_offset=0 + [3] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED + [4] STRUCT 'my_struct' size=48 vlen=6 + 'const_int_field' type_id=5 bits_offset=0 + 'bitfield_field' type_id=3 bits_offset=32 bitfield_size=4 + 'arr_field' type_id=8 bits_offset=40 + 'fwd_field' type_id=10 bits_offset=192 + 'enum_field' type_id=14 bits_offset=256 + 'typedef_ptr_field' type_id=15 bits_offset=320 + [5] CONST '(anon)' type_id=6 + [6] INT 'unsigned int' size=4 bits_offset=0 nr_bits=32 encoding=(none) + [7] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=SIGNED + [8] ARRAY '(anon)' type_id=7 index_type_id=9 nr_elems=16 + [9] INT '__ARRAY_SIZE_TYPE__' size=4 bits_offset=0 nr_bits=32 encoding=(none) + [10] RESTRICT '(anon)' type_id=11 + [11] PTR '(anon)' type_id=12 + [12] CONST '(anon)' type_id=13 + [13] FWD 'fwd_struct' fwd_kind=union + [14] ENUM 'my_enum' size=4 vlen=2 + 'VAL1' val=3 + 'VAL2' val=7 + [15] PTR '(anon)' type_id=16 + [16] VOLATILE '(anon)' type_id=17 + [17] TYPEDEF 'my_struct_t' type_id=4 + [18] FUNC_PROTO '(anon)' ret_type_id=3 vlen=2 + 'arg1' type_id=1 + 'arg2' type_id=3 + [19] FUNC 'my_func' type_id=18 + [20] VAR 'struct_global_var' type_id=4, linkage=global-alloc + [21] VAR 'global_var' type_id=3, linkage=global-alloc + [22] VAR 'my_func.static_var' type_id=3, linkage=static + [23] DATASEC 'data_sec' size=0 vlen=3 + type_id=20 offset=0 size=48 + type_id=21 offset=0 size=4 + type_id=22 offset=52 size=4 + +The following commands print BTF types associated with specified map's key, +value, both key and value, and all BTF types, respectively. By default, both +key and value types will be printed. + +**# bpftool btf dump map id 123 key** + +:: + + [39] TYPEDEF 'u32' type_id=37 + +**# bpftool btf dump map id 123 value** + +:: + + [86] PTR '(anon)' type_id=87 + +**# bpftool btf dump map id 123 kv** + +:: + + [39] TYPEDEF 'u32' type_id=37 + [86] PTR '(anon)' type_id=87 + +**# bpftool btf dump map id 123 all** + +:: + + [1] PTR '(anon)' type_id=0 + . + . + . + [2866] ARRAY '(anon)' type_id=52 index_type_id=51 nr_elems=4 + +All the standard ways to specify map or program are supported: + +**# bpftool btf dump map id 123** + +**# bpftool btf dump map pinned /sys/fs/bpf/map_name** + +**# bpftool btf dump prog id 456** + +**# bpftool btf dump prog tag b88e0a09b1d9759d** + +**# bpftool btf dump prog pinned /sys/fs/bpf/prog_name** + +| +| **# bpftool btf dump file /sys/kernel/btf/i2c_smbus** +| (or) +| **# I2C_SMBUS_ID=$(bpftool btf show -p | jq '.[] | select(.name=="i2c_smbus").id')** +| **# bpftool btf dump id ${I2C_SMBUS_ID} -B /sys/kernel/btf/vmlinux** + +:: + + [104848] STRUCT 'i2c_smbus_alert' size=40 vlen=2 + 'alert' type_id=393 bits_offset=0 + 'ara' type_id=56050 bits_offset=256 + [104849] STRUCT 'alert_data' size=12 vlen=3 + 'addr' type_id=16 bits_offset=0 + 'type' type_id=56053 bits_offset=32 + 'data' type_id=7 bits_offset=64 + [104850] PTR '(anon)' type_id=104848 + [104851] PTR '(anon)' type_id=104849 + [104852] FUNC 'i2c_register_spd' type_id=84745 linkage=static + [104853] FUNC 'smbalert_driver_init' type_id=1213 linkage=static + [104854] FUNC_PROTO '(anon)' ret_type_id=18 vlen=1 + 'ara' type_id=56050 + [104855] FUNC 'i2c_handle_smbus_alert' type_id=104854 linkage=static + [104856] FUNC 'smbalert_remove' type_id=104854 linkage=static + [104857] FUNC_PROTO '(anon)' ret_type_id=18 vlen=2 + 'ara' type_id=56050 + 'id' type_id=56056 + [104858] FUNC 'smbalert_probe' type_id=104857 linkage=static + [104859] FUNC 'smbalert_work' type_id=9695 linkage=static + [104860] FUNC 'smbus_alert' type_id=71367 linkage=static + [104861] FUNC 'smbus_do_alert' type_id=84827 linkage=static diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst new file mode 100644 index 000000000..bd015ec98 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst @@ -0,0 +1,157 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-cgroup +================ +------------------------------------------------------------------------------- +tool for inspection and simple manipulation of eBPF progs +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **cgroup** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } } + + *COMMANDS* := + { **show** | **list** | **tree** | **attach** | **detach** | **help** } + +CGROUP COMMANDS +=============== + +| **bpftool** **cgroup** { **show** | **list** } *CGROUP* [**effective**] +| **bpftool** **cgroup tree** [*CGROUP_ROOT*] [**effective**] +| **bpftool** **cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*] +| **bpftool** **cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG* +| **bpftool** **cgroup help** +| +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } +| *ATTACH_TYPE* := { **cgroup_inet_ingress** | **cgroup_inet_egress** | +| **cgroup_inet_sock_create** | **cgroup_sock_ops** | +| **cgroup_device** | **cgroup_inet4_bind** | **cgroup_inet6_bind** | +| **cgroup_inet4_post_bind** | **cgroup_inet6_post_bind** | +| **cgroup_inet4_connect** | **cgroup_inet6_connect** | +| **cgroup_inet4_getpeername** | **cgroup_inet6_getpeername** | +| **cgroup_inet4_getsockname** | **cgroup_inet6_getsockname** | +| **cgroup_udp4_sendmsg** | **cgroup_udp6_sendmsg** | +| **cgroup_udp4_recvmsg** | **cgroup_udp6_recvmsg** | +| **cgroup_sysctl** | **cgroup_getsockopt** | **cgroup_setsockopt** | +| **cgroup_inet_sock_release** } +| *ATTACH_FLAGS* := { **multi** | **override** } + +DESCRIPTION +=========== + **bpftool cgroup { show | list }** *CGROUP* [**effective**] + List all programs attached to the cgroup *CGROUP*. + + Output will start with program ID followed by attach type, + attach flags and program name. + + If **effective** is specified retrieve effective programs that + will execute for events within a cgroup. This includes + inherited along with attached ones. + + **bpftool cgroup tree** [*CGROUP_ROOT*] [**effective**] + Iterate over all cgroups in *CGROUP_ROOT* and list all + attached programs. If *CGROUP_ROOT* is not specified, + bpftool uses cgroup v2 mountpoint. + + The output is similar to the output of cgroup show/list + commands: it starts with absolute cgroup path, followed by + program ID, attach type, attach flags and program name. + + If **effective** is specified retrieve effective programs that + will execute for events within a cgroup. This includes + inherited along with attached ones. + + **bpftool cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*] + Attach program *PROG* to the cgroup *CGROUP* with attach type + *ATTACH_TYPE* and optional *ATTACH_FLAGS*. + + *ATTACH_FLAGS* can be one of: **override** if a sub-cgroup installs + some bpf program, the program in this cgroup yields to sub-cgroup + program; **multi** if a sub-cgroup installs some bpf program, + that cgroup program gets run in addition to the program in this + cgroup. + + Only one program is allowed to be attached to a cgroup with + no attach flags or the **override** flag. Attaching another + program will release old program and attach the new one. + + Multiple programs are allowed to be attached to a cgroup with + **multi**. They are executed in FIFO order (those that were + attached first, run first). + + Non-default *ATTACH_FLAGS* are supported by kernel version 4.14 + and later. + + *ATTACH_TYPE* can be on of: + **ingress** ingress path of the inet socket (since 4.10); + **egress** egress path of the inet socket (since 4.10); + **sock_create** opening of an inet socket (since 4.10); + **sock_ops** various socket operations (since 4.12); + **device** device access (since 4.15); + **bind4** call to bind(2) for an inet4 socket (since 4.17); + **bind6** call to bind(2) for an inet6 socket (since 4.17); + **post_bind4** return from bind(2) for an inet4 socket (since 4.17); + **post_bind6** return from bind(2) for an inet6 socket (since 4.17); + **connect4** call to connect(2) for an inet4 socket (since 4.17); + **connect6** call to connect(2) for an inet6 socket (since 4.17); + **sendmsg4** call to sendto(2), sendmsg(2), sendmmsg(2) for an + unconnected udp4 socket (since 4.18); + **sendmsg6** call to sendto(2), sendmsg(2), sendmmsg(2) for an + unconnected udp6 socket (since 4.18); + **recvmsg4** call to recvfrom(2), recvmsg(2), recvmmsg(2) for + an unconnected udp4 socket (since 5.2); + **recvmsg6** call to recvfrom(2), recvmsg(2), recvmmsg(2) for + an unconnected udp6 socket (since 5.2); + **sysctl** sysctl access (since 5.2); + **getsockopt** call to getsockopt (since 5.3); + **setsockopt** call to setsockopt (since 5.3); + **getpeername4** call to getpeername(2) for an inet4 socket (since 5.8); + **getpeername6** call to getpeername(2) for an inet6 socket (since 5.8); + **getsockname4** call to getsockname(2) for an inet4 socket (since 5.8); + **getsockname6** call to getsockname(2) for an inet6 socket (since 5.8). + **sock_release** closing an userspace inet socket (since 5.9). + + **bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG* + Detach *PROG* from the cgroup *CGROUP* and attach type + *ATTACH_TYPE*. + + **bpftool prog help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -f, --bpffs + Show file names of pinned programs. + +EXAMPLES +======== +| +| **# mount -t bpf none /sys/fs/bpf/** +| **# mkdir /sys/fs/cgroup/test.slice** +| **# bpftool prog load ./device_cgroup.o /sys/fs/bpf/prog** +| **# bpftool cgroup attach /sys/fs/cgroup/test.slice/ device id 1 allow_multi** + +**# bpftool cgroup list /sys/fs/cgroup/test.slice/** + +:: + + ID AttachType AttachFlags Name + 1 device allow_multi bpf_prog1 + +| +| **# bpftool cgroup detach /sys/fs/cgroup/test.slice/ device id 1** +| **# bpftool cgroup list /sys/fs/cgroup/test.slice/** + +:: + + ID AttachType AttachFlags Name diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst new file mode 100644 index 000000000..e44039f89 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst @@ -0,0 +1,90 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +=============== +bpftool-feature +=============== +------------------------------------------------------------------------------- +tool for inspection of eBPF-related parameters for Linux kernel or net device +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **feature** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| } + + *COMMANDS* := { **probe** | **help** } + +FEATURE COMMANDS +================ + +| **bpftool** **feature probe** [*COMPONENT*] [**full**] [**unprivileged**] [**macros** [**prefix** *PREFIX*]] +| **bpftool** **feature list_builtins** *GROUP* +| **bpftool** **feature help** +| +| *COMPONENT* := { **kernel** | **dev** *NAME* } +| *GROUP* := { **prog_types** | **map_types** | **attach_types** | **link_types** | **helpers** } + +DESCRIPTION +=========== + **bpftool feature probe** [**kernel**] [**full**] [**macros** [**prefix** *PREFIX*]] + Probe the running kernel and dump a number of eBPF-related + parameters, such as availability of the **bpf**\ () system call, + JIT status, eBPF program types availability, eBPF helper + functions availability, and more. + + By default, bpftool **does not run probes** for + **bpf_probe_write_user**\ () and **bpf_trace_printk**\() + helpers which print warnings to kernel logs. To enable them + and run all probes, the **full** keyword should be used. + + If the **macros** keyword (but not the **-j** option) is + passed, a subset of the output is dumped as a list of + **#define** macros that are ready to be included in a C + header file, for example. If, additionally, **prefix** is + used to define a *PREFIX*, the provided string will be used + as a prefix to the names of the macros: this can be used to + avoid conflicts on macro names when including the output of + this command as a header file. + + Keyword **kernel** can be omitted. If no probe target is + specified, probing the kernel is the default behaviour. + + When the **unprivileged** keyword is used, bpftool will dump + only the features available to a user who does not have the + **CAP_SYS_ADMIN** capability set. The features available in + that case usually represent a small subset of the parameters + supported by the system. Unprivileged users MUST use the + **unprivileged** keyword: This is to avoid misdetection if + bpftool is inadvertently run as non-root, for example. This + keyword is unavailable if bpftool was compiled without + libcap. + + **bpftool feature probe dev** *NAME* [**full**] [**macros** [**prefix** *PREFIX*]] + Probe network device for supported eBPF features and dump + results to the console. + + The keywords **full**, **macros** and **prefix** have the + same role as when probing the kernel. + + **bpftool feature list_builtins** *GROUP* + List items known to bpftool. These can be BPF program types + (**prog_types**), BPF map types (**map_types**), attach types + (**attach_types**), link types (**link_types**), or BPF helper + functions (**helpers**). The command does not probe the system, but + simply lists the elements that bpftool knows from compilation time, + as provided from libbpf (for all object types) or from the BPF UAPI + header (list of helpers). This can be used in scripts to iterate over + BPF types or helpers. + + **bpftool feature help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst new file mode 100644 index 000000000..5006e724d --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst @@ -0,0 +1,446 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-gen +================ +------------------------------------------------------------------------------- +tool for BPF code-generation +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **gen** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | { **-L** | **--use-loader** } } + + *COMMAND* := { **object** | **skeleton** | **help** } + +GEN COMMANDS +============= + +| **bpftool** **gen object** *OUTPUT_FILE* *INPUT_FILE* [*INPUT_FILE*...] +| **bpftool** **gen skeleton** *FILE* [**name** *OBJECT_NAME*] +| **bpftool** **gen subskeleton** *FILE* [**name** *OBJECT_NAME*] +| **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] +| **bpftool** **gen help** + +DESCRIPTION +=========== + **bpftool gen object** *OUTPUT_FILE* *INPUT_FILE* [*INPUT_FILE*...] + Statically link (combine) together one or more *INPUT_FILE*'s + into a single resulting *OUTPUT_FILE*. All the files involved + are BPF ELF object files. + + The rules of BPF static linking are mostly the same as for + user-space object files, but in addition to combining data + and instruction sections, .BTF and .BTF.ext (if present in + any of the input files) data are combined together. .BTF + data is deduplicated, so all the common types across + *INPUT_FILE*'s will only be represented once in the resulting + BTF information. + + BPF static linking allows to partition BPF source code into + individually compiled files that are then linked into + a single resulting BPF object file, which can be used to + generated BPF skeleton (with **gen skeleton** command) or + passed directly into **libbpf** (using **bpf_object__open()** + family of APIs). + + **bpftool gen skeleton** *FILE* + Generate BPF skeleton C header file for a given *FILE*. + + BPF skeleton is an alternative interface to existing libbpf + APIs for working with BPF objects. Skeleton code is intended + to significantly shorten and simplify code to load and work + with BPF programs from userspace side. Generated code is + tailored to specific input BPF object *FILE*, reflecting its + structure by listing out available maps, program, variables, + etc. Skeleton eliminates the need to lookup mentioned + components by name. Instead, if skeleton instantiation + succeeds, they are populated in skeleton structure as valid + libbpf types (e.g., **struct bpf_map** pointer) and can be + passed to existing generic libbpf APIs. + + In addition to simple and reliable access to maps and + programs, skeleton provides a storage for BPF links (**struct + bpf_link**) for each BPF program within BPF object. When + requested, supported BPF programs will be automatically + attached and resulting BPF links stored for further use by + user in pre-allocated fields in skeleton struct. For BPF + programs that can't be automatically attached by libbpf, + user can attach them manually, but store resulting BPF link + in per-program link field. All such set up links will be + automatically destroyed on BPF skeleton destruction. This + eliminates the need for users to manage links manually and + rely on libbpf support to detach programs and free up + resources. + + Another facility provided by BPF skeleton is an interface to + global variables of all supported kinds: mutable, read-only, + as well as extern ones. This interface allows to pre-setup + initial values of variables before BPF object is loaded and + verified by kernel. For non-read-only variables, the same + interface can be used to fetch values of global variables on + userspace side, even if they are modified by BPF code. + + During skeleton generation, contents of source BPF object + *FILE* is embedded within generated code and is thus not + necessary to keep around. This ensures skeleton and BPF + object file are matching 1-to-1 and always stay in sync. + Generated code is dual-licensed under LGPL-2.1 and + BSD-2-Clause licenses. + + It is a design goal and guarantee that skeleton interfaces + are interoperable with generic libbpf APIs. User should + always be able to use skeleton API to create and load BPF + object, and later use libbpf APIs to keep working with + specific maps, programs, etc. + + As part of skeleton, few custom functions are generated. + Each of them is prefixed with object name. Object name can + either be derived from object file name, i.e., if BPF object + file name is **example.o**, BPF object name will be + **example**. Object name can be also specified explicitly + through **name** *OBJECT_NAME* parameter. The following + custom functions are provided (assuming **example** as + the object name): + + - **example__open** and **example__open_opts**. + These functions are used to instantiate skeleton. It + corresponds to libbpf's **bpf_object__open**\ () API. + **_opts** variants accepts extra **bpf_object_open_opts** + options. + + - **example__load**. + This function creates maps, loads and verifies BPF + programs, initializes global data maps. It corresponds to + libppf's **bpf_object__load**\ () API. + + - **example__open_and_load** combines **example__open** and + **example__load** invocations in one commonly used + operation. + + - **example__attach** and **example__detach** + This pair of functions allow to attach and detach, + correspondingly, already loaded BPF object. Only BPF + programs of types supported by libbpf for auto-attachment + will be auto-attached and their corresponding BPF links + instantiated. For other BPF programs, user can manually + create a BPF link and assign it to corresponding fields in + skeleton struct. **example__detach** will detach both + links created automatically, as well as those populated by + user manually. + + - **example__destroy** + Detach and unload BPF programs, free up all the resources + used by skeleton and BPF object. + + If BPF object has global variables, corresponding structs + with memory layout corresponding to global data data section + layout will be created. Currently supported ones are: *.data*, + *.bss*, *.rodata*, and *.kconfig* structs/data sections. + These data sections/structs can be used to set up initial + values of variables, if set before **example__load**. + Afterwards, if target kernel supports memory-mapped BPF + arrays, same structs can be used to fetch and update + (non-read-only) data from userspace, with same simplicity + as for BPF side. + + **bpftool gen subskeleton** *FILE* + Generate BPF subskeleton C header file for a given *FILE*. + + Subskeletons are similar to skeletons, except they do not own + the corresponding maps, programs, or global variables. They + require that the object file used to generate them is already + loaded into a *bpf_object* by some other means. + + This functionality is useful when a library is included into a + larger BPF program. A subskeleton for the library would have + access to all objects and globals defined in it, without + having to know about the larger program. + + Consequently, there are only two functions defined + for subskeletons: + + - **example__open(bpf_object\*)** + Instantiates a subskeleton from an already opened (but not + necessarily loaded) **bpf_object**. + + - **example__destroy()** + Frees the storage for the subskeleton but *does not* unload + any BPF programs or maps. + + **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] + Generate a minimum BTF file as *OUTPUT*, derived from a given + *INPUT* BTF file, containing all needed BTF types so one, or + more, given eBPF objects CO-RE relocations may be satisfied. + + When kernels aren't compiled with CONFIG_DEBUG_INFO_BTF, + libbpf, when loading an eBPF object, has to rely on external + BTF files to be able to calculate CO-RE relocations. + + Usually, an external BTF file is built from existing kernel + DWARF data using pahole. It contains all the types used by + its respective kernel image and, because of that, is big. + + The min_core_btf feature builds smaller BTF files, customized + to one or multiple eBPF objects, so they can be distributed + together with an eBPF CO-RE based application, turning the + application portable to different kernel versions. + + Check examples bellow for more information how to use it. + + **bpftool gen help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -L, --use-loader + For skeletons, generate a "light" skeleton (also known as "loader" + skeleton). A light skeleton contains a loader eBPF program. It does + not use the majority of the libbpf infrastructure, and does not need + libelf. + +EXAMPLES +======== +**$ cat example1.bpf.c** + +:: + + #include <stdbool.h> + #include <linux/ptrace.h> + #include <linux/bpf.h> + #include <bpf/bpf_helpers.h> + + const volatile int param1 = 42; + bool global_flag = true; + struct { int x; } data = {}; + + SEC("raw_tp/sys_enter") + int handle_sys_enter(struct pt_regs *ctx) + { + static long my_static_var; + if (global_flag) + my_static_var++; + else + data.x += param1; + return 0; + } + +**$ cat example2.bpf.c** + +:: + + #include <linux/ptrace.h> + #include <linux/bpf.h> + #include <bpf/bpf_helpers.h> + + struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 128); + __type(key, int); + __type(value, long); + } my_map SEC(".maps"); + + SEC("raw_tp/sys_exit") + int handle_sys_exit(struct pt_regs *ctx) + { + int zero = 0; + bpf_map_lookup_elem(&my_map, &zero); + return 0; + } + +This is example BPF application with two BPF programs and a mix of BPF maps +and global variables. Source code is split across two source code files. + +**$ clang --target=bpf -g example1.bpf.c -o example1.bpf.o** + +**$ clang --target=bpf -g example2.bpf.c -o example2.bpf.o** + +**$ bpftool gen object example.bpf.o example1.bpf.o example2.bpf.o** + +This set of commands compiles *example1.bpf.c* and *example2.bpf.c* +individually and then statically links respective object files into the final +BPF ELF object file *example.bpf.o*. + +**$ bpftool gen skeleton example.bpf.o name example | tee example.skel.h** + +:: + + /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + + /* THIS FILE IS AUTOGENERATED! */ + #ifndef __EXAMPLE_SKEL_H__ + #define __EXAMPLE_SKEL_H__ + + #include <stdlib.h> + #include <bpf/libbpf.h> + + struct example { + struct bpf_object_skeleton *skeleton; + struct bpf_object *obj; + struct { + struct bpf_map *rodata; + struct bpf_map *data; + struct bpf_map *bss; + struct bpf_map *my_map; + } maps; + struct { + struct bpf_program *handle_sys_enter; + struct bpf_program *handle_sys_exit; + } progs; + struct { + struct bpf_link *handle_sys_enter; + struct bpf_link *handle_sys_exit; + } links; + struct example__bss { + struct { + int x; + } data; + } *bss; + struct example__data { + _Bool global_flag; + long int handle_sys_enter_my_static_var; + } *data; + struct example__rodata { + int param1; + } *rodata; + }; + + static void example__destroy(struct example *obj); + static inline struct example *example__open_opts( + const struct bpf_object_open_opts *opts); + static inline struct example *example__open(); + static inline int example__load(struct example *obj); + static inline struct example *example__open_and_load(); + static inline int example__attach(struct example *obj); + static inline void example__detach(struct example *obj); + + #endif /* __EXAMPLE_SKEL_H__ */ + +**$ cat example.c** + +:: + + #include "example.skel.h" + + int main() + { + struct example *skel; + int err = 0; + + skel = example__open(); + if (!skel) + goto cleanup; + + skel->rodata->param1 = 128; + + err = example__load(skel); + if (err) + goto cleanup; + + err = example__attach(skel); + if (err) + goto cleanup; + + /* all libbpf APIs are usable */ + printf("my_map name: %s\n", bpf_map__name(skel->maps.my_map)); + printf("sys_enter prog FD: %d\n", + bpf_program__fd(skel->progs.handle_sys_enter)); + + /* detach and re-attach sys_exit program */ + bpf_link__destroy(skel->links.handle_sys_exit); + skel->links.handle_sys_exit = + bpf_program__attach(skel->progs.handle_sys_exit); + + printf("my_static_var: %ld\n", + skel->bss->handle_sys_enter_my_static_var); + + cleanup: + example__destroy(skel); + return err; + } + +**# ./example** + +:: + + my_map name: my_map + sys_enter prog FD: 8 + my_static_var: 7 + +This is a stripped-out version of skeleton generated for above example code. + +min_core_btf +------------ + +**$ bpftool btf dump file 5.4.0-example.btf format raw** + +:: + + [1] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) + [2] CONST '(anon)' type_id=1 + [3] VOLATILE '(anon)' type_id=1 + [4] ARRAY '(anon)' type_id=1 index_type_id=21 nr_elems=2 + [5] PTR '(anon)' type_id=8 + [6] CONST '(anon)' type_id=5 + [7] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=(none) + [8] CONST '(anon)' type_id=7 + [9] INT 'unsigned int' size=4 bits_offset=0 nr_bits=32 encoding=(none) + <long output> + +**$ bpftool btf dump file one.bpf.o format raw** + +:: + + [1] PTR '(anon)' type_id=2 + [2] STRUCT 'trace_event_raw_sys_enter' size=64 vlen=4 + 'ent' type_id=3 bits_offset=0 + 'id' type_id=7 bits_offset=64 + 'args' type_id=9 bits_offset=128 + '__data' type_id=12 bits_offset=512 + [3] STRUCT 'trace_entry' size=8 vlen=4 + 'type' type_id=4 bits_offset=0 + 'flags' type_id=5 bits_offset=16 + 'preempt_count' type_id=5 bits_offset=24 + <long output> + +**$ bpftool gen min_core_btf 5.4.0-example.btf 5.4.0-smaller.btf one.bpf.o** + +**$ bpftool btf dump file 5.4.0-smaller.btf format raw** + +:: + + [1] TYPEDEF 'pid_t' type_id=6 + [2] STRUCT 'trace_event_raw_sys_enter' size=64 vlen=1 + 'args' type_id=4 bits_offset=128 + [3] STRUCT 'task_struct' size=9216 vlen=2 + 'pid' type_id=1 bits_offset=17920 + 'real_parent' type_id=7 bits_offset=18048 + [4] ARRAY '(anon)' type_id=5 index_type_id=8 nr_elems=6 + [5] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) + [6] TYPEDEF '__kernel_pid_t' type_id=8 + [7] PTR '(anon)' type_id=3 + [8] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED + <end> + +Now, the "5.4.0-smaller.btf" file may be used by libbpf as an external BTF file +when loading the "one.bpf.o" object into the "5.4.0-example" kernel. Note that +the generated BTF file won't allow other eBPF objects to be loaded, just the +ones given to min_core_btf. + +:: + + LIBBPF_OPTS(bpf_object_open_opts, opts, .btf_custom_path = "5.4.0-smaller.btf"); + struct bpf_object *obj; + + obj = bpf_object__open_file("one.bpf.o", &opts); + + ... diff --git a/tools/bpf/bpftool/Documentation/bpftool-iter.rst b/tools/bpf/bpftool/Documentation/bpftool-iter.rst new file mode 100644 index 000000000..84839d488 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-iter.rst @@ -0,0 +1,76 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +============ +bpftool-iter +============ +------------------------------------------------------------------------------- +tool to create BPF iterators +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **iter** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| } + + *COMMANDS* := { **pin** | **help** } + +ITER COMMANDS +=================== + +| **bpftool** **iter pin** *OBJ* *PATH* [**map** *MAP*] +| **bpftool** **iter help** +| +| *OBJ* := /a/file/of/bpf_iter_target.o +| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } + +DESCRIPTION +=========== + **bpftool iter pin** *OBJ* *PATH* [**map** *MAP*] + A bpf iterator combines a kernel iterating of + particular kernel data (e.g., tasks, bpf_maps, etc.) + and a bpf program called for each kernel data object + (e.g., one task, one bpf_map, etc.). User space can + *read* kernel iterator output through *read()* syscall. + + The *pin* command creates a bpf iterator from *OBJ*, + and pin it to *PATH*. The *PATH* should be located + in *bpffs* mount. It must not contain a dot + character ('.'), which is reserved for future extensions + of *bpffs*. + + Map element bpf iterator requires an additional parameter + *MAP* so bpf program can iterate over map elements for + that map. User can have a bpf program in kernel to run + with each map element, do checking, filtering, aggregation, + etc. without copying data to user space. + + User can then *cat PATH* to see the bpf iterator output. + + **bpftool iter help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + +EXAMPLES +======== +**# bpftool iter pin bpf_iter_netlink.o /sys/fs/bpf/my_netlink** + +:: + + Create a file-based bpf iterator from bpf_iter_netlink.o and pin it + to /sys/fs/bpf/my_netlink + +**# bpftool iter pin bpf_iter_hashmap.o /sys/fs/bpf/my_hashmap map id 20** + +:: + + Create a file-based bpf iterator from bpf_iter_hashmap.o and map with + id 20, and pin it to /sys/fs/bpf/my_hashmap diff --git a/tools/bpf/bpftool/Documentation/bpftool-link.rst b/tools/bpf/bpftool/Documentation/bpftool-link.rst new file mode 100644 index 000000000..52a4eee4a --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-link.rst @@ -0,0 +1,112 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-link +================ +------------------------------------------------------------------------------- +tool for inspection and simple manipulation of eBPF links +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **link** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } | { **-n** | **--nomount** } } + + *COMMANDS* := { **show** | **list** | **pin** | **help** } + +LINK COMMANDS +============= + +| **bpftool** **link { show | list }** [*LINK*] +| **bpftool** **link pin** *LINK* *FILE* +| **bpftool** **link detach** *LINK* +| **bpftool** **link help** +| +| *LINK* := { **id** *LINK_ID* | **pinned** *FILE* } + + +DESCRIPTION +=========== + **bpftool link { show | list }** [*LINK*] + Show information about active links. If *LINK* is + specified show information only about given link, + otherwise list all links currently active on the system. + + Output will start with link ID followed by link type and + zero or more named attributes, some of which depend on type + of link. + + Since Linux 5.8 bpftool is able to discover information about + processes that hold open file descriptors (FDs) against BPF + links. On such kernels bpftool will automatically emit this + information as well. + + **bpftool link pin** *LINK* *FILE* + Pin link *LINK* as *FILE*. + + Note: *FILE* must be located in *bpffs* mount. It must not + contain a dot character ('.'), which is reserved for future + extensions of *bpffs*. + + **bpftool link detach** *LINK* + Force-detach link *LINK*. BPF link and its underlying BPF + program will stay valid, but they will be detached from the + respective BPF hook and BPF link will transition into + a defunct state until last open file descriptor for that + link is closed. + + **bpftool link help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -f, --bpffs + When showing BPF links, show file names of pinned + links. + + -n, --nomount + Do not automatically attempt to mount any virtual file system + (such as tracefs or BPF virtual file system) when necessary. + +EXAMPLES +======== +**# bpftool link show** + +:: + + 10: cgroup prog 25 + cgroup_id 614 attach_type egress + pids test_progs(223) + +**# bpftool --json --pretty link show** + +:: + + [{ + "type": "cgroup", + "prog_id": 25, + "cgroup_id": 614, + "attach_type": "egress", + "pids": [{ + "pid": 223, + "comm": "test_progs" + } + ] + } + ] + +| +| **# bpftool link pin id 10 /sys/fs/bpf/link** +| **# ls -l /sys/fs/bpf/** + +:: + + -rw------- 1 root root 0 Apr 23 21:39 link diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst new file mode 100644 index 000000000..3b7ba037a --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst @@ -0,0 +1,277 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-map +================ +------------------------------------------------------------------------------- +tool for inspection and simple manipulation of eBPF maps +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **map** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } | { **-n** | **--nomount** } } + + *COMMANDS* := + { **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext** | + **delete** | **pin** | **help** } + +MAP COMMANDS +============= + +| **bpftool** **map** { **show** | **list** } [*MAP*] +| **bpftool** **map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* \ +| **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**inner_map** *MAP*] \ +| [**offload_dev** *NAME*] +| **bpftool** **map dump** *MAP* +| **bpftool** **map update** *MAP* [**key** *DATA*] [**value** *VALUE*] [*UPDATE_FLAGS*] +| **bpftool** **map lookup** *MAP* [**key** *DATA*] +| **bpftool** **map getnext** *MAP* [**key** *DATA*] +| **bpftool** **map delete** *MAP* **key** *DATA* +| **bpftool** **map pin** *MAP* *FILE* +| **bpftool** **map event_pipe** *MAP* [**cpu** *N* **index** *M*] +| **bpftool** **map peek** *MAP* +| **bpftool** **map push** *MAP* **value** *VALUE* +| **bpftool** **map pop** *MAP* +| **bpftool** **map enqueue** *MAP* **value** *VALUE* +| **bpftool** **map dequeue** *MAP* +| **bpftool** **map freeze** *MAP* +| **bpftool** **map help** +| +| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* | **name** *MAP_NAME* } +| *DATA* := { [**hex**] *BYTES* } +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* | **name** *PROG_NAME* } +| *VALUE* := { *DATA* | *MAP* | *PROG* } +| *UPDATE_FLAGS* := { **any** | **exist** | **noexist** } +| *TYPE* := { **hash** | **array** | **prog_array** | **perf_event_array** | **percpu_hash** +| | **percpu_array** | **stack_trace** | **cgroup_array** | **lru_hash** +| | **lru_percpu_hash** | **lpm_trie** | **array_of_maps** | **hash_of_maps** +| | **devmap** | **devmap_hash** | **sockmap** | **cpumap** | **xskmap** | **sockhash** +| | **cgroup_storage** | **reuseport_sockarray** | **percpu_cgroup_storage** +| | **queue** | **stack** | **sk_storage** | **struct_ops** | **ringbuf** | **inode_storage** +| | **task_storage** | **bloom_filter** | **user_ringbuf** | **cgrp_storage** } + +DESCRIPTION +=========== + **bpftool map { show | list }** [*MAP*] + Show information about loaded maps. If *MAP* is specified + show information only about given maps, otherwise list all + maps currently loaded on the system. In case of **name**, + *MAP* may match several maps which will all be shown. + + Output will start with map ID followed by map type and + zero or more named attributes (depending on kernel version). + + Since Linux 5.8 bpftool is able to discover information about + processes that hold open file descriptors (FDs) against BPF + maps. On such kernels bpftool will automatically emit this + information as well. + + **bpftool map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**inner_map** *MAP*] [**offload_dev** *NAME*] + Create a new map with given parameters and pin it to *bpffs* + as *FILE*. + + *FLAGS* should be an integer which is the combination of + desired flags, e.g. 1024 for **BPF_F_MMAPABLE** (see bpf.h + UAPI header for existing flags). + + To create maps of type array-of-maps or hash-of-maps, the + **inner_map** keyword must be used to pass an inner map. The + kernel needs it to collect metadata related to the inner maps + that the new map will work with. + + Keyword **offload_dev** expects a network interface name, + and is used to request hardware offload for the map. + + **bpftool map dump** *MAP* + Dump all entries in a given *MAP*. In case of **name**, + *MAP* may match several maps which will all be dumped. + + **bpftool map update** *MAP* [**key** *DATA*] [**value** *VALUE*] [*UPDATE_FLAGS*] + Update map entry for a given *KEY*. + + *UPDATE_FLAGS* can be one of: **any** update existing entry + or add if doesn't exit; **exist** update only if entry already + exists; **noexist** update only if entry doesn't exist. + + If the **hex** keyword is provided in front of the bytes + sequence, the bytes are parsed as hexadecimal values, even if + no "0x" prefix is added. If the keyword is not provided, then + the bytes are parsed as decimal values, unless a "0x" prefix + (for hexadecimal) or a "0" prefix (for octal) is provided. + + **bpftool map lookup** *MAP* [**key** *DATA*] + Lookup **key** in the map. + + **bpftool map getnext** *MAP* [**key** *DATA*] + Get next key. If *key* is not specified, get first key. + + **bpftool map delete** *MAP* **key** *DATA* + Remove entry from the map. + + **bpftool map pin** *MAP* *FILE* + Pin map *MAP* as *FILE*. + + Note: *FILE* must be located in *bpffs* mount. It must not + contain a dot character ('.'), which is reserved for future + extensions of *bpffs*. + + **bpftool** **map event_pipe** *MAP* [**cpu** *N* **index** *M*] + Read events from a **BPF_MAP_TYPE_PERF_EVENT_ARRAY** map. + + Install perf rings into a perf event array map and dump + output of any **bpf_perf_event_output**\ () call in the kernel. + By default read the number of CPUs on the system and + install perf ring for each CPU in the corresponding index + in the array. + + If **cpu** and **index** are specified, install perf ring + for given **cpu** at **index** in the array (single ring). + + Note that installing a perf ring into an array will silently + replace any existing ring. Any other application will stop + receiving events if it installed its rings earlier. + + **bpftool map peek** *MAP* + Peek next value in the queue or stack. + + **bpftool map push** *MAP* **value** *VALUE* + Push *VALUE* onto the stack. + + **bpftool map pop** *MAP* + Pop and print value from the stack. + + **bpftool map enqueue** *MAP* **value** *VALUE* + Enqueue *VALUE* into the queue. + + **bpftool map dequeue** *MAP* + Dequeue and print value from the queue. + + **bpftool map freeze** *MAP* + Freeze the map as read-only from user space. Entries from a + frozen map can not longer be updated or deleted with the + **bpf**\ () system call. This operation is not reversible, + and the map remains immutable from user space until its + destruction. However, read and write permissions for BPF + programs to the map remain unchanged. + + **bpftool map help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -f, --bpffs + Show file names of pinned maps. + + -n, --nomount + Do not automatically attempt to mount any virtual file system + (such as tracefs or BPF virtual file system) when necessary. + +EXAMPLES +======== +**# bpftool map show** + +:: + + 10: hash name some_map flags 0x0 + key 4B value 8B max_entries 2048 memlock 167936B + pids systemd(1) + +The following three commands are equivalent: + +| +| **# bpftool map update id 10 key hex 20 c4 b7 00 value hex 0f ff ff ab 01 02 03 4c** +| **# bpftool map update id 10 key 0x20 0xc4 0xb7 0x00 value 0x0f 0xff 0xff 0xab 0x01 0x02 0x03 0x4c** +| **# bpftool map update id 10 key 32 196 183 0 value 15 255 255 171 1 2 3 76** + +**# bpftool map lookup id 10 key 0 1 2 3** + +:: + + key: 00 01 02 03 value: 00 01 02 03 04 05 06 07 + + +**# bpftool map dump id 10** + +:: + + key: 00 01 02 03 value: 00 01 02 03 04 05 06 07 + key: 0d 00 07 00 value: 02 00 00 00 01 02 03 04 + Found 2 elements + +**# bpftool map getnext id 10 key 0 1 2 3** + +:: + + key: + 00 01 02 03 + next key: + 0d 00 07 00 + +| +| **# mount -t bpf none /sys/fs/bpf/** +| **# bpftool map pin id 10 /sys/fs/bpf/map** +| **# bpftool map del pinned /sys/fs/bpf/map key 13 00 07 00** + +Note that map update can also be used in order to change the program references +hold by a program array map. This can be used, for example, to change the +programs used for tail-call jumps at runtime, without having to reload the +entry-point program. Below is an example for this use case: we load a program +defining a prog array map, and with a main function that contains a tail call +to other programs that can be used either to "process" packets or to "debug" +processing. Note that the prog array map MUST be pinned into the BPF virtual +file system for the map update to work successfully, as kernel flushes prog +array maps when they have no more references from user space (and the update +would be lost as soon as bpftool exits). + +| +| **# bpftool prog loadall tail_calls.o /sys/fs/bpf/foo type xdp** +| **# bpftool prog --bpffs** + +:: + + 545: xdp name main_func tag 674b4b5597193dc3 gpl + loaded_at 2018-12-12T15:02:58+0000 uid 0 + xlated 240B jited 257B memlock 4096B map_ids 294 + pinned /sys/fs/bpf/foo/xdp + 546: xdp name bpf_func_process tag e369a529024751fc gpl + loaded_at 2018-12-12T15:02:58+0000 uid 0 + xlated 200B jited 164B memlock 4096B + pinned /sys/fs/bpf/foo/process + 547: xdp name bpf_func_debug tag 0b597868bc7f0976 gpl + loaded_at 2018-12-12T15:02:58+0000 uid 0 + xlated 200B jited 164B memlock 4096B + pinned /sys/fs/bpf/foo/debug + +**# bpftool map** + +:: + + 294: prog_array name jmp_table flags 0x0 + key 4B value 4B max_entries 1 memlock 4096B + owner_prog_type xdp owner jited + +| +| **# bpftool map pin id 294 /sys/fs/bpf/bar** +| **# bpftool map dump pinned /sys/fs/bpf/bar** + +:: + + Found 0 elements + +| +| **# bpftool map update pinned /sys/fs/bpf/bar key 0 0 0 0 value pinned /sys/fs/bpf/foo/debug** +| **# bpftool map dump pinned /sys/fs/bpf/bar** + +:: + + key: 00 00 00 00 value: 22 02 00 00 + Found 1 element diff --git a/tools/bpf/bpftool/Documentation/bpftool-net.rst b/tools/bpf/bpftool/Documentation/bpftool-net.rst new file mode 100644 index 000000000..5e2abd3de --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-net.rst @@ -0,0 +1,182 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-net +================ +------------------------------------------------------------------------------- +tool for inspection of networking related bpf prog attachments +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **net** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| } + + *COMMANDS* := + { **show** | **list** | **attach** | **detach** | **help** } + +NET COMMANDS +============ + +| **bpftool** **net** { **show** | **list** } [ **dev** *NAME* ] +| **bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ] +| **bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME* +| **bpftool** **net help** +| +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } +| *ATTACH_TYPE* := { **xdp** | **xdpgeneric** | **xdpdrv** | **xdpoffload** } + +DESCRIPTION +=========== + **bpftool net { show | list }** [ **dev** *NAME* ] + List bpf program attachments in the kernel networking subsystem. + + Currently, device driver xdp attachments, tcx and old-style tc + classifier/action attachments, flow_dissector as well as netfilter + attachments are implemented, i.e., for + program types **BPF_PROG_TYPE_XDP**, **BPF_PROG_TYPE_SCHED_CLS**, + **BPF_PROG_TYPE_SCHED_ACT**, **BPF_PROG_TYPE_FLOW_DISSECTOR**, + **BPF_PROG_TYPE_NETFILTER**. + + For programs attached to a particular cgroup, e.g., + **BPF_PROG_TYPE_CGROUP_SKB**, **BPF_PROG_TYPE_CGROUP_SOCK**, + **BPF_PROG_TYPE_SOCK_OPS** and **BPF_PROG_TYPE_CGROUP_SOCK_ADDR**, + users can use **bpftool cgroup** to dump cgroup attachments. + For sk_{filter, skb, msg, reuseport} and lwt/seg6 + bpf programs, users should consult other tools, e.g., iproute2. + + The current output will start with all xdp program attachments, followed by + all tcx, then tc class/qdisc bpf program attachments, then flow_dissector + and finally netfilter programs. Both xdp programs and tcx/tc programs are + ordered based on ifindex number. If multiple bpf programs attached + to the same networking device through **tc**, the order will be first + all bpf programs attached to tcx, then tc classes, then all bpf programs + attached to non clsact qdiscs, and finally all bpf programs attached + to root and clsact qdisc. + + **bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ] + Attach bpf program *PROG* to network interface *NAME* with + type specified by *ATTACH_TYPE*. Previously attached bpf program + can be replaced by the command used with **overwrite** option. + Currently, only XDP-related modes are supported for *ATTACH_TYPE*. + + *ATTACH_TYPE* can be of: + **xdp** - try native XDP and fallback to generic XDP if NIC driver does not support it; + **xdpgeneric** - Generic XDP. runs at generic XDP hook when packet already enters receive path as skb; + **xdpdrv** - Native XDP. runs earliest point in driver's receive path; + **xdpoffload** - Offload XDP. runs directly on NIC on each packet reception; + + **bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME* + Detach bpf program attached to network interface *NAME* with + type specified by *ATTACH_TYPE*. To detach bpf program, same + *ATTACH_TYPE* previously used for attach must be specified. + Currently, only XDP-related modes are supported for *ATTACH_TYPE*. + + **bpftool net help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + +EXAMPLES +======== + +| **# bpftool net** + +:: + + xdp: + eth0(2) driver id 198 + + tc: + eth0(2) htb name prefix_matcher.o:[cls_prefix_matcher_htb] id 111727 act [] + eth0(2) clsact/ingress fbflow_icmp id 130246 act [] + eth0(2) clsact/egress prefix_matcher.o:[cls_prefix_matcher_clsact] id 111726 + eth0(2) clsact/egress cls_fg_dscp id 108619 act [] + eth0(2) clsact/egress fbflow_egress id 130245 + +| +| **# bpftool -jp net** + +:: + + [{ + "xdp": [{ + "devname": "eth0", + "ifindex": 2, + "mode": "driver", + "id": 198 + } + ], + "tc": [{ + "devname": "eth0", + "ifindex": 2, + "kind": "htb", + "name": "prefix_matcher.o:[cls_prefix_matcher_htb]", + "id": 111727, + "act": [] + },{ + "devname": "eth0", + "ifindex": 2, + "kind": "clsact/ingress", + "name": "fbflow_icmp", + "id": 130246, + "act": [] + },{ + "devname": "eth0", + "ifindex": 2, + "kind": "clsact/egress", + "name": "prefix_matcher.o:[cls_prefix_matcher_clsact]", + "id": 111726, + },{ + "devname": "eth0", + "ifindex": 2, + "kind": "clsact/egress", + "name": "cls_fg_dscp", + "id": 108619, + "act": [] + },{ + "devname": "eth0", + "ifindex": 2, + "kind": "clsact/egress", + "name": "fbflow_egress", + "id": 130245, + } + ] + } + ] + +| +| **# bpftool net attach xdpdrv id 16 dev enp6s0np0** +| **# bpftool net** + +:: + + xdp: + enp6s0np0(4) driver id 16 + +| +| **# bpftool net attach xdpdrv id 16 dev enp6s0np0** +| **# bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite** +| **# bpftool net** + +:: + + xdp: + enp6s0np0(4) driver id 20 + +| +| **# bpftool net attach xdpdrv id 16 dev enp6s0np0** +| **# bpftool net detach xdpdrv dev enp6s0np0** +| **# bpftool net** + +:: + + xdp: diff --git a/tools/bpf/bpftool/Documentation/bpftool-perf.rst b/tools/bpf/bpftool/Documentation/bpftool-perf.rst new file mode 100644 index 000000000..5fea633a8 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-perf.rst @@ -0,0 +1,69 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-perf +================ +------------------------------------------------------------------------------- +tool for inspection of perf related bpf prog attachments +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **perf** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| } + + *COMMANDS* := + { **show** | **list** | **help** } + +PERF COMMANDS +============= + +| **bpftool** **perf** { **show** | **list** } +| **bpftool** **perf help** + +DESCRIPTION +=========== + **bpftool perf { show | list }** + List all raw_tracepoint, tracepoint, kprobe attachment in the system. + + Output will start with process id and file descriptor in that process, + followed by bpf program id, attachment information, and attachment point. + The attachment point for raw_tracepoint/tracepoint is the trace probe name. + The attachment point for k[ret]probe is either symbol name and offset, + or a kernel virtual address. + The attachment point for u[ret]probe is the file name and the file offset. + + **bpftool perf help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + +EXAMPLES +======== + +| **# bpftool perf** + +:: + + pid 21711 fd 5: prog_id 5 kprobe func __x64_sys_write offset 0 + pid 21765 fd 5: prog_id 7 kretprobe func __x64_sys_nanosleep offset 0 + pid 21767 fd 5: prog_id 8 tracepoint sys_enter_nanosleep + pid 21800 fd 5: prog_id 9 uprobe filename /home/yhs/a.out offset 1159 + +| +| **# bpftool -j perf** + +:: + + [{"pid":21711,"fd":5,"prog_id":5,"fd_type":"kprobe","func":"__x64_sys_write","offset":0}, \ + {"pid":21765,"fd":5,"prog_id":7,"fd_type":"kretprobe","func":"__x64_sys_nanosleep","offset":0}, \ + {"pid":21767,"fd":5,"prog_id":8,"fd_type":"tracepoint","tracepoint":"sys_enter_nanosleep"}, \ + {"pid":21800,"fd":5,"prog_id":9,"fd_type":"uprobe","filename":"/home/yhs/a.out","offset":1159}] diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst new file mode 100644 index 000000000..dcae81bd2 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -0,0 +1,375 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +bpftool-prog +================ +------------------------------------------------------------------------------- +tool for inspection and simple manipulation of eBPF progs +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **prog** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| | + { **-f** | **--bpffs** } | { **-m** | **--mapcompat** } | { **-n** | **--nomount** } | + { **-L** | **--use-loader** } } + + *COMMANDS* := + { **show** | **list** | **dump xlated** | **dump jited** | **pin** | **load** | + **loadall** | **help** } + +PROG COMMANDS +============= + +| **bpftool** **prog** { **show** | **list** } [*PROG*] +| **bpftool** **prog dump xlated** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] [**visual**] }] +| **bpftool** **prog dump jited** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] }] +| **bpftool** **prog pin** *PROG* *FILE* +| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** { **idx** *IDX* | **name** *NAME* } *MAP*] [{ **offload_dev** | **xdpmeta_dev** } *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**] +| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*] +| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*] +| **bpftool** **prog tracelog** +| **bpftool** **prog run** *PROG* **data_in** *FILE* [**data_out** *FILE* [**data_size_out** *L*]] [**ctx_in** *FILE* [**ctx_out** *FILE* [**ctx_size_out** *M*]]] [**repeat** *N*] +| **bpftool** **prog profile** *PROG* [**duration** *DURATION*] *METRICs* +| **bpftool** **prog help** +| +| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* | **name** *PROG_NAME* } +| *TYPE* := { +| **socket** | **kprobe** | **kretprobe** | **classifier** | **action** | +| **tracepoint** | **raw_tracepoint** | **xdp** | **perf_event** | **cgroup/skb** | +| **cgroup/sock** | **cgroup/dev** | **lwt_in** | **lwt_out** | **lwt_xmit** | +| **lwt_seg6local** | **sockops** | **sk_skb** | **sk_msg** | **lirc_mode2** | +| **cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** | +| **cgroup/connect4** | **cgroup/connect6** | **cgroup/getpeername4** | **cgroup/getpeername6** | +| **cgroup/getsockname4** | **cgroup/getsockname6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** | +| **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl** | +| **cgroup/getsockopt** | **cgroup/setsockopt** | **cgroup/sock_release** | +| **struct_ops** | **fentry** | **fexit** | **freplace** | **sk_lookup** +| } +| *ATTACH_TYPE* := { +| **sk_msg_verdict** | **sk_skb_verdict** | **sk_skb_stream_verdict** | +| **sk_skb_stream_parser** | **flow_dissector** +| } +| *METRICs* := { +| **cycles** | **instructions** | **l1d_loads** | **llc_misses** | +| **itlb_misses** | **dtlb_misses** +| } + + +DESCRIPTION +=========== + **bpftool prog { show | list }** [*PROG*] + Show information about loaded programs. If *PROG* is + specified show information only about given programs, + otherwise list all programs currently loaded on the system. + In case of **tag** or **name**, *PROG* may match several + programs which will all be shown. + + Output will start with program ID followed by program type and + zero or more named attributes (depending on kernel version). + + Since Linux 5.1 the kernel can collect statistics on BPF + programs (such as the total time spent running the program, + and the number of times it was run). If available, bpftool + shows such statistics. However, the kernel does not collect + them by defaults, as it slightly impacts performance on each + program run. Activation or deactivation of the feature is + performed via the **kernel.bpf_stats_enabled** sysctl knob. + + Since Linux 5.8 bpftool is able to discover information about + processes that hold open file descriptors (FDs) against BPF + programs. On such kernels bpftool will automatically emit this + information as well. + + **bpftool prog dump xlated** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] [**visual**] }] + Dump eBPF instructions of the programs from the kernel. By + default, eBPF will be disassembled and printed to standard + output in human-readable format. In this case, **opcodes** + controls if raw opcodes should be printed as well. + + In case of **tag** or **name**, *PROG* may match several + programs which will all be dumped. However, if **file** or + **visual** is specified, *PROG* must match a single program. + + If **file** is specified, the binary image will instead be + written to *FILE*. + + If **visual** is specified, control flow graph (CFG) will be + built instead, and eBPF instructions will be presented with + CFG in DOT format, on standard output. + + If the programs have line_info available, the source line will + be displayed. If **linum** is specified, the filename, line + number and line column will also be displayed. + + **bpftool prog dump jited** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] }] + Dump jited image (host machine code) of the program. + + If *FILE* is specified image will be written to a file, + otherwise it will be disassembled and printed to stdout. + *PROG* must match a single program when **file** is specified. + + **opcodes** controls if raw opcodes will be printed. + + If the prog has line_info available, the source line will + be displayed. If **linum** is specified, the filename, line + number and line column will also be displayed. + + **bpftool prog pin** *PROG* *FILE* + Pin program *PROG* as *FILE*. + + Note: *FILE* must be located in *bpffs* mount. It must not + contain a dot character ('.'), which is reserved for future + extensions of *bpffs*. + + **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** { **idx** *IDX* | **name** *NAME* } *MAP*] [{ **offload_dev** | **xdpmeta_dev** } *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**] + Load bpf program(s) from binary *OBJ* and pin as *PATH*. + **bpftool prog load** pins only the first program from the + *OBJ* as *PATH*. **bpftool prog loadall** pins all programs + from the *OBJ* under *PATH* directory. + **type** is optional, if not specified program type will be + inferred from section names. + By default bpftool will create new maps as declared in the ELF + object being loaded. **map** parameter allows for the reuse + of existing maps. It can be specified multiple times, each + time for a different map. *IDX* refers to index of the map + to be replaced in the ELF file counting from 0, while *NAME* + allows to replace a map by name. *MAP* specifies the map to + use, referring to it by **id** or through a **pinned** file. + If **offload_dev** *NAME* is specified program will be loaded + onto given networking device (offload). + If **xdpmeta_dev** *NAME* is specified program will become + device-bound without offloading, this facilitates access + to XDP metadata. + Optional **pinmaps** argument can be provided to pin all + maps under *MAP_DIR* directory. + + If **autoattach** is specified program will be attached + before pin. In that case, only the link (representing the + program attached to its hook) is pinned, not the program as + such, so the path won't show in **bpftool prog show -f**, + only show in **bpftool link show -f**. Also, this only works + when bpftool (libbpf) is able to infer all necessary + information from the object file, in particular, it's not + supported for all program types. If a program does not + support autoattach, bpftool falls back to regular pinning + for that program instead. + + Note: *PATH* must be located in *bpffs* mount. It must not + contain a dot character ('.'), which is reserved for future + extensions of *bpffs*. + + **bpftool prog attach** *PROG* *ATTACH_TYPE* [*MAP*] + Attach bpf program *PROG* (with type specified by + *ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP* + parameter, with the exception of *flow_dissector* which is + attached to current networking name space. + + **bpftool prog detach** *PROG* *ATTACH_TYPE* [*MAP*] + Detach bpf program *PROG* (with type specified by + *ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP* + parameter, with the exception of *flow_dissector* which is + detached from the current networking name space. + + **bpftool prog tracelog** + Dump the trace pipe of the system to the console (stdout). + Hit <Ctrl+C> to stop printing. BPF programs can write to this + trace pipe at runtime with the **bpf_trace_printk**\ () helper. + This should be used only for debugging purposes. For + streaming data from BPF programs to user space, one can use + perf events (see also **bpftool-map**\ (8)). + + **bpftool prog run** *PROG* **data_in** *FILE* [**data_out** *FILE* [**data_size_out** *L*]] [**ctx_in** *FILE* [**ctx_out** *FILE* [**ctx_size_out** *M*]]] [**repeat** *N*] + Run BPF program *PROG* in the kernel testing infrastructure + for BPF, meaning that the program works on the data and + context provided by the user, and not on actual packets or + monitored functions etc. Return value and duration for the + test run are printed out to the console. + + Input data is read from the *FILE* passed with **data_in**. + If this *FILE* is "**-**", input data is read from standard + input. Input context, if any, is read from *FILE* passed with + **ctx_in**. Again, "**-**" can be used to read from standard + input, but only if standard input is not already in use for + input data. If a *FILE* is passed with **data_out**, output + data is written to that file. Similarly, output context is + written to the *FILE* passed with **ctx_out**. For both + output flows, "**-**" can be used to print to the standard + output (as plain text, or JSON if relevant option was + passed). If output keywords are omitted, output data and + context are discarded. Keywords **data_size_out** and + **ctx_size_out** are used to pass the size (in bytes) for the + output buffers to the kernel, although the default of 32 kB + should be more than enough for most cases. + + Keyword **repeat** is used to indicate the number of + consecutive runs to perform. Note that output data and + context printed to files correspond to the last of those + runs. The duration printed out at the end of the runs is an + average over all runs performed by the command. + + Not all program types support test run. Among those which do, + not all of them can take the **ctx_in**/**ctx_out** + arguments. bpftool does not perform checks on program types. + + **bpftool prog profile** *PROG* [**duration** *DURATION*] *METRICs* + Profile *METRICs* for bpf program *PROG* for *DURATION* + seconds or until user hits <Ctrl+C>. *DURATION* is optional. + If *DURATION* is not specified, the profiling will run up to + **UINT_MAX** seconds. + + **bpftool prog help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + + -f, --bpffs + When showing BPF programs, show file names of pinned + programs. + + -m, --mapcompat + Allow loading maps with unknown map definitions. + + -n, --nomount + Do not automatically attempt to mount any virtual file system + (such as tracefs or BPF virtual file system) when necessary. + + -L, --use-loader + Load program as a "loader" program. This is useful to debug + the generation of such programs. When this option is in + use, bpftool attempts to load the programs from the object + file into the kernel, but does not pin them (therefore, the + *PATH* must not be provided). + + When combined with the **-d**\ \|\ **--debug** option, + additional debug messages are generated, and the execution + of the loader program will use the **bpf_trace_printk**\ () + helper to log each step of loading BTF, creating the maps, + and loading the programs (see **bpftool prog tracelog** as + a way to dump those messages). + +EXAMPLES +======== +**# bpftool prog show** + +:: + + 10: xdp name some_prog tag 005a3d2123620c8b gpl run_time_ns 81632 run_cnt 10 + loaded_at 2017-09-29T20:11:00+0000 uid 0 + xlated 528B jited 370B memlock 4096B map_ids 10 + pids systemd(1) + +**# bpftool --json --pretty prog show** + +:: + + [{ + "id": 10, + "type": "xdp", + "tag": "005a3d2123620c8b", + "gpl_compatible": true, + "run_time_ns": 81632, + "run_cnt": 10, + "loaded_at": 1506715860, + "uid": 0, + "bytes_xlated": 528, + "jited": true, + "bytes_jited": 370, + "bytes_memlock": 4096, + "map_ids": [10 + ], + "pids": [{ + "pid": 1, + "comm": "systemd" + } + ] + } + ] + +| +| **# bpftool prog dump xlated id 10 file /tmp/t** +| **$ ls -l /tmp/t** + +:: + + -rw------- 1 root root 560 Jul 22 01:42 /tmp/t + +**# bpftool prog dump jited tag 005a3d2123620c8b** + +:: + + 0: push %rbp + 1: mov %rsp,%rbp + 2: sub $0x228,%rsp + 3: sub $0x28,%rbp + 4: mov %rbx,0x0(%rbp) + +| +| **# mount -t bpf none /sys/fs/bpf/** +| **# bpftool prog pin id 10 /sys/fs/bpf/prog** +| **# bpftool prog load ./my_prog.o /sys/fs/bpf/prog2** +| **# ls -l /sys/fs/bpf/** + +:: + + -rw------- 1 root root 0 Jul 22 01:43 prog + -rw------- 1 root root 0 Jul 22 01:44 prog2 + +**# bpftool prog dump jited pinned /sys/fs/bpf/prog opcodes** + +:: + + 0: push %rbp + 55 + 1: mov %rsp,%rbp + 48 89 e5 + 4: sub $0x228,%rsp + 48 81 ec 28 02 00 00 + b: sub $0x28,%rbp + 48 83 ed 28 + f: mov %rbx,0x0(%rbp) + 48 89 5d 00 + +| +| **# bpftool prog load xdp1_kern.o /sys/fs/bpf/xdp1 type xdp map name rxcnt id 7** +| **# bpftool prog show pinned /sys/fs/bpf/xdp1** + +:: + + 9: xdp name xdp_prog1 tag 539ec6ce11b52f98 gpl + loaded_at 2018-06-25T16:17:31-0700 uid 0 + xlated 488B jited 336B memlock 4096B map_ids 7 + +**# rm /sys/fs/bpf/xdp1** + +| +| **# bpftool prog profile id 337 duration 10 cycles instructions llc_misses** + +:: + + 51397 run_cnt + 40176203 cycles (83.05%) + 42518139 instructions # 1.06 insns per cycle (83.39%) + 123 llc_misses # 2.89 LLC misses per million insns (83.15%) + +| +| Output below is for the trace logs. +| Run in separate terminals: +| **# bpftool prog tracelog** +| **# bpftool prog load -L -d file.o** + +:: + + bpftool-620059 [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5 + bpftool-620059 [004] d... 2634685.517912: bpf_trace_printk: map_create sample_map idx 0 type 2 value_size 4 value_btf_id 0 r=6 + bpftool-620059 [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7 + bpftool-620059 [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0 diff --git a/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst b/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst new file mode 100644 index 000000000..8022b5321 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst @@ -0,0 +1,92 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================== +bpftool-struct_ops +================== +------------------------------------------------------------------------------- +tool to register/unregister/introspect BPF struct_ops +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] **struct_ops** *COMMAND* + + *OPTIONS* := { |COMMON_OPTIONS| } + + *COMMANDS* := + { **show** | **list** | **dump** | **register** | **unregister** | **help** } + +STRUCT_OPS COMMANDS +=================== + +| **bpftool** **struct_ops { show | list }** [*STRUCT_OPS_MAP*] +| **bpftool** **struct_ops dump** [*STRUCT_OPS_MAP*] +| **bpftool** **struct_ops register** *OBJ* [*LINK_DIR*] +| **bpftool** **struct_ops unregister** *STRUCT_OPS_MAP* +| **bpftool** **struct_ops help** +| +| *STRUCT_OPS_MAP* := { **id** *STRUCT_OPS_MAP_ID* | **name** *STRUCT_OPS_MAP_NAME* } +| *OBJ* := /a/file/of/bpf_struct_ops.o + + +DESCRIPTION +=========== + **bpftool struct_ops { show | list }** [*STRUCT_OPS_MAP*] + Show brief information about the struct_ops in the system. + If *STRUCT_OPS_MAP* is specified, it shows information only + for the given struct_ops. Otherwise, it lists all struct_ops + currently existing in the system. + + Output will start with struct_ops map ID, followed by its map + name and its struct_ops's kernel type. + + **bpftool struct_ops dump** [*STRUCT_OPS_MAP*] + Dump details information about the struct_ops in the system. + If *STRUCT_OPS_MAP* is specified, it dumps information only + for the given struct_ops. Otherwise, it dumps all struct_ops + currently existing in the system. + + **bpftool struct_ops register** *OBJ* [*LINK_DIR*] + Register bpf struct_ops from *OBJ*. All struct_ops under + the ELF section ".struct_ops" and ".struct_ops.link" will + be registered to its kernel subsystem. For each + struct_ops in the ".struct_ops.link" section, a link + will be created. You can give *LINK_DIR* to provide a + directory path where these links will be pinned with the + same name as their corresponding map name. + + **bpftool struct_ops unregister** *STRUCT_OPS_MAP* + Unregister the *STRUCT_OPS_MAP* from the kernel subsystem. + + **bpftool struct_ops help** + Print short help message. + +OPTIONS +======= + .. include:: common_options.rst + +EXAMPLES +======== +**# bpftool struct_ops show** + +:: + + 100: dctcp tcp_congestion_ops + 105: cubic tcp_congestion_ops + +**# bpftool struct_ops unregister id 105** + +:: + + Unregistered tcp_congestion_ops cubic id 105 + +**# bpftool struct_ops register bpf_cubic.o** + +:: + + Registered tcp_congestion_ops cubic id 110 diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst new file mode 100644 index 000000000..6965c94df --- /dev/null +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -0,0 +1,70 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +================ +BPFTOOL +================ +------------------------------------------------------------------------------- +tool for inspection and simple manipulation of eBPF programs and maps +------------------------------------------------------------------------------- + +:Manual section: 8 + +.. include:: substitutions.rst + +SYNOPSIS +======== + + **bpftool** [*OPTIONS*] *OBJECT* { *COMMAND* | **help** } + + **bpftool** **batch file** *FILE* + + **bpftool** **version** + + *OBJECT* := { **map** | **program** | **link** | **cgroup** | **perf** | **net** | **feature** | + **btf** | **gen** | **struct_ops** | **iter** } + + *OPTIONS* := { { **-V** | **--version** } | |COMMON_OPTIONS| } + + *MAP-COMMANDS* := + { **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext** | + **delete** | **pin** | **event_pipe** | **help** } + + *PROG-COMMANDS* := { **show** | **list** | **dump jited** | **dump xlated** | **pin** | + **load** | **attach** | **detach** | **help** } + + *LINK-COMMANDS* := { **show** | **list** | **pin** | **detach** | **help** } + + *CGROUP-COMMANDS* := { **show** | **list** | **attach** | **detach** | **help** } + + *PERF-COMMANDS* := { **show** | **list** | **help** } + + *NET-COMMANDS* := { **show** | **list** | **help** } + + *FEATURE-COMMANDS* := { **probe** | **help** } + + *BTF-COMMANDS* := { **show** | **list** | **dump** | **help** } + + *GEN-COMMANDS* := { **object** | **skeleton** | **min_core_btf** | **help** } + + *STRUCT-OPS-COMMANDS* := { **show** | **list** | **dump** | **register** | **unregister** | **help** } + + *ITER-COMMANDS* := { **pin** | **help** } + +DESCRIPTION +=========== + *bpftool* allows for inspection and simple modification of BPF objects + on the system. + + Note that format of the output of all tools is not guaranteed to be + stable and should not be depended upon. + +OPTIONS +======= + .. include:: common_options.rst + + -m, --mapcompat + Allow loading maps with unknown map definitions. + + -n, --nomount + Do not automatically attempt to mount any virtual file system + (such as tracefs or BPF virtual file system) when necessary. diff --git a/tools/bpf/bpftool/Documentation/common_options.rst b/tools/bpf/bpftool/Documentation/common_options.rst new file mode 100644 index 000000000..30df7a707 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/common_options.rst @@ -0,0 +1,25 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +-h, --help + Print short help message (similar to **bpftool help**). + +-V, --version + Print bpftool's version number (similar to **bpftool version**), the + number of the libbpf version in use, and optional features that were + included when bpftool was compiled. Optional features include linking + against LLVM or libbfd to provide the disassembler for JIT-ted + programs (**bpftool prog dump jited**) and usage of BPF skeletons + (some features like **bpftool prog profile** or showing pids + associated to BPF objects may rely on it). + +-j, --json + Generate JSON output. For commands that cannot produce JSON, this + option has no effect. + +-p, --pretty + Generate human-readable JSON output. Implies **-j**. + +-d, --debug + Print all logs available, even debug-level information. This includes + logs from libbpf as well as from the verifier, when attempting to + load programs. diff --git a/tools/bpf/bpftool/Documentation/substitutions.rst b/tools/bpf/bpftool/Documentation/substitutions.rst new file mode 100644 index 000000000..827e3ffb1 --- /dev/null +++ b/tools/bpf/bpftool/Documentation/substitutions.rst @@ -0,0 +1,3 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +.. |COMMON_OPTIONS| replace:: { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } |