1.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2 3================ 4bpftool-prog 5================ 6------------------------------------------------------------------------------- 7tool for inspection and simple manipulation of eBPF progs 8------------------------------------------------------------------------------- 9 10:Manual section: 8 11 12.. include:: substitutions.rst 13 14SYNOPSIS 15======== 16 17**bpftool** [*OPTIONS*] **prog** *COMMAND* 18 19*OPTIONS* := { |COMMON_OPTIONS| | 20{ **-f** | **--bpffs** } | { **-m** | **--mapcompat** } | { **-n** | **--nomount** } | 21{ **-L** | **--use-loader** } } 22 23*COMMANDS* := 24{ **show** | **list** | **dump xlated** | **dump jited** | **pin** | **load** | 25**loadall** | **help** } 26 27PROG COMMANDS 28============= 29 30| **bpftool** **prog** { **show** | **list** } [*PROG*] 31| **bpftool** **prog dump xlated** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] [**visual**] }] 32| **bpftool** **prog dump jited** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] }] 33| **bpftool** **prog pin** *PROG* *FILE* 34| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** { **idx** *IDX* | **name** *NAME* } *MAP*] [{ **offload_dev** | **xdpmeta_dev** } *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**] 35| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*] 36| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*] 37| **bpftool** **prog tracelog** 38| **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*] 39| **bpftool** **prog profile** *PROG* [**duration** *DURATION*] *METRICs* 40| **bpftool** **prog help** 41| 42| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* | **name** *MAP_NAME* } 43| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* | **name** *PROG_NAME* } 44| *TYPE* := { 45| **socket** | **kprobe** | **kretprobe** | **classifier** | **action** | 46| **tracepoint** | **raw_tracepoint** | **xdp** | **perf_event** | **cgroup/skb** | 47| **cgroup/sock** | **cgroup/dev** | **lwt_in** | **lwt_out** | **lwt_xmit** | 48| **lwt_seg6local** | **sockops** | **sk_skb** | **sk_msg** | **lirc_mode2** | 49| **cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** | 50| **cgroup/connect4** | **cgroup/connect6** | **cgroup/connect_unix** | 51| **cgroup/getpeername4** | **cgroup/getpeername6** | **cgroup/getpeername_unix** | 52| **cgroup/getsockname4** | **cgroup/getsockname6** | **cgroup/getsockname_unix** | 53| **cgroup/sendmsg4** | **cgroup/sendmsg6** | **cgroup/sendmsg_unix** | 54| **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/recvmsg_unix** | **cgroup/sysctl** | 55| **cgroup/getsockopt** | **cgroup/setsockopt** | **cgroup/sock_release** | 56| **struct_ops** | **fentry** | **fexit** | **freplace** | **sk_lookup** 57| } 58| *ATTACH_TYPE* := { 59| **sk_msg_verdict** | **sk_skb_verdict** | **sk_skb_stream_verdict** | 60| **sk_skb_stream_parser** | **flow_dissector** 61| } 62| *METRICs* := { 63| **cycles** | **instructions** | **l1d_loads** | **llc_misses** | 64| **itlb_misses** | **dtlb_misses** 65| } 66 67 68DESCRIPTION 69=========== 70bpftool prog { show | list } [*PROG*] 71 Show information about loaded programs. If *PROG* is specified show 72 information only about given programs, otherwise list all programs 73 currently loaded on the system. In case of **tag** or **name**, *PROG* may 74 match several programs which will all be shown. 75 76 Output will start with program ID followed by program type and zero or more 77 named attributes (depending on kernel version). 78 79 Since Linux 5.1 the kernel can collect statistics on BPF programs (such as 80 the total time spent running the program, and the number of times it was 81 run). If available, bpftool shows such statistics. However, the kernel does 82 not collect them by defaults, as it slightly impacts performance on each 83 program run. Activation or deactivation of the feature is performed via the 84 **kernel.bpf_stats_enabled** sysctl knob. 85 86 Since Linux 5.8 bpftool is able to discover information about processes 87 that hold open file descriptors (FDs) against BPF programs. On such kernels 88 bpftool will automatically emit this information as well. 89 90bpftool prog dump xlated *PROG* [{ file *FILE* | [opcodes] [linum] [visual] }] 91 Dump eBPF instructions of the programs from the kernel. By default, eBPF 92 will be disassembled and printed to standard output in human-readable 93 format. In this case, **opcodes** controls if raw opcodes should be printed 94 as well. 95 96 In case of **tag** or **name**, *PROG* may match several programs which 97 will all be dumped. However, if **file** or **visual** is specified, 98 *PROG* must match a single program. 99 100 If **file** is specified, the binary image will instead be written to 101 *FILE*. 102 103 If **visual** is specified, control flow graph (CFG) will be built instead, 104 and eBPF instructions will be presented with CFG in DOT format, on standard 105 output. 106 107 If the programs have line_info available, the source line will be 108 displayed. If **linum** is specified, the filename, line number and line 109 column will also be displayed. 110 111bpftool prog dump jited *PROG* [{ file *FILE* | [opcodes] [linum] }] 112 Dump jited image (host machine code) of the program. 113 114 If *FILE* is specified image will be written to a file, otherwise it will 115 be disassembled and printed to stdout. *PROG* must match a single program 116 when **file** is specified. 117 118 **opcodes** controls if raw opcodes will be printed. 119 120 If the prog has line_info available, the source line will be displayed. If 121 **linum** is specified, the filename, line number and line column will also 122 be displayed. 123 124bpftool prog pin *PROG* *FILE* 125 Pin program *PROG* as *FILE*. 126 127 Note: *FILE* must be located in *bpffs* mount. It must not contain a dot 128 character ('.'), which is reserved for future extensions of *bpffs*. 129 130bpftool prog { load | loadall } *OBJ* *PATH* [type *TYPE*] [map { idx *IDX* | name *NAME* } *MAP*] [{ offload_dev | xdpmeta_dev } *NAME*] [pinmaps *MAP_DIR*] [autoattach] 131 Load bpf program(s) from binary *OBJ* and pin as *PATH*. **bpftool prog 132 load** pins only the first program from the *OBJ* as *PATH*. **bpftool prog 133 loadall** pins all programs from the *OBJ* under *PATH* directory. **type** 134 is optional, if not specified program type will be inferred from section 135 names. By default bpftool will create new maps as declared in the ELF 136 object being loaded. **map** parameter allows for the reuse of existing 137 maps. It can be specified multiple times, each time for a different map. 138 *IDX* refers to index of the map to be replaced in the ELF file counting 139 from 0, while *NAME* allows to replace a map by name. *MAP* specifies the 140 map to use, referring to it by **id** or through a **pinned** file. If 141 **offload_dev** *NAME* is specified program will be loaded onto given 142 networking device (offload). If **xdpmeta_dev** *NAME* is specified program 143 will become device-bound without offloading, this facilitates access to XDP 144 metadata. Optional **pinmaps** argument can be provided to pin all maps 145 under *MAP_DIR* directory. 146 147 If **autoattach** is specified program will be attached before pin. In that 148 case, only the link (representing the program attached to its hook) is 149 pinned, not the program as such, so the path won't show in **bpftool prog 150 show -f**, only show in **bpftool link show -f**. Also, this only works 151 when bpftool (libbpf) is able to infer all necessary information from the 152 object file, in particular, it's not supported for all program types. If a 153 program does not support autoattach, bpftool falls back to regular pinning 154 for that program instead. 155 156 Note: *PATH* must be located in *bpffs* mount. It must not contain a dot 157 character ('.'), which is reserved for future extensions of *bpffs*. 158 159bpftool prog attach *PROG* *ATTACH_TYPE* [*MAP*] 160 Attach bpf program *PROG* (with type specified by *ATTACH_TYPE*). Most 161 *ATTACH_TYPEs* require a *MAP* parameter, with the exception of 162 *flow_dissector* which is attached to current networking name space. 163 164bpftool prog detach *PROG* *ATTACH_TYPE* [*MAP*] 165 Detach bpf program *PROG* (with type specified by *ATTACH_TYPE*). Most 166 *ATTACH_TYPEs* require a *MAP* parameter, with the exception of 167 *flow_dissector* which is detached from the current networking name space. 168 169bpftool prog tracelog 170 Dump the trace pipe of the system to the console (stdout). Hit <Ctrl+C> to 171 stop printing. BPF programs can write to this trace pipe at runtime with 172 the **bpf_trace_printk**\ () helper. This should be used only for debugging 173 purposes. For streaming data from BPF programs to user space, one can use 174 perf events (see also **bpftool-map**\ (8)). 175 176bpftool 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*] 177 Run BPF program *PROG* in the kernel testing infrastructure for BPF, 178 meaning that the program works on the data and context provided by the 179 user, and not on actual packets or monitored functions etc. Return value 180 and duration for the test run are printed out to the console. 181 182 Input data is read from the *FILE* passed with **data_in**. If this *FILE* 183 is "**-**", input data is read from standard input. Input context, if any, 184 is read from *FILE* passed with **ctx_in**. Again, "**-**" can be used to 185 read from standard input, but only if standard input is not already in use 186 for input data. If a *FILE* is passed with **data_out**, output data is 187 written to that file. Similarly, output context is written to the *FILE* 188 passed with **ctx_out**. For both output flows, "**-**" can be used to 189 print to the standard output (as plain text, or JSON if relevant option was 190 passed). If output keywords are omitted, output data and context are 191 discarded. Keywords **data_size_out** and **ctx_size_out** are used to pass 192 the size (in bytes) for the output buffers to the kernel, although the 193 default of 32 kB should be more than enough for most cases. 194 195 Keyword **repeat** is used to indicate the number of consecutive runs to 196 perform. Note that output data and context printed to files correspond to 197 the last of those runs. The duration printed out at the end of the runs is 198 an average over all runs performed by the command. 199 200 Not all program types support test run. Among those which do, not all of 201 them can take the **ctx_in**/**ctx_out** arguments. bpftool does not 202 perform checks on program types. 203 204bpftool prog profile *PROG* [duration *DURATION*] *METRICs* 205 Profile *METRICs* for bpf program *PROG* for *DURATION* seconds or until 206 user hits <Ctrl+C>. *DURATION* is optional. If *DURATION* is not specified, 207 the profiling will run up to **UINT_MAX** seconds. 208 209bpftool prog help 210 Print short help message. 211 212OPTIONS 213======= 214.. include:: common_options.rst 215 216-f, --bpffs 217 When showing BPF programs, show file names of pinned programs. 218 219-m, --mapcompat 220 Allow loading maps with unknown map definitions. 221 222-n, --nomount 223 Do not automatically attempt to mount any virtual file system (such as 224 tracefs or BPF virtual file system) when necessary. 225 226-L, --use-loader 227 Load program as a "loader" program. This is useful to debug the generation 228 of such programs. When this option is in use, bpftool attempts to load the 229 programs from the object file into the kernel, but does not pin them 230 (therefore, the *PATH* must not be provided). 231 232 When combined with the **-d**\ \|\ **--debug** option, additional debug 233 messages are generated, and the execution of the loader program will use 234 the **bpf_trace_printk**\ () helper to log each step of loading BTF, 235 creating the maps, and loading the programs (see **bpftool prog tracelog** 236 as a way to dump those messages). 237 238EXAMPLES 239======== 240**# bpftool prog show** 241 242:: 243 244 10: xdp name some_prog tag 005a3d2123620c8b gpl run_time_ns 81632 run_cnt 10 245 loaded_at 2017-09-29T20:11:00+0000 uid 0 246 xlated 528B jited 370B memlock 4096B map_ids 10 247 pids systemd(1) 248 249**# bpftool --json --pretty prog show** 250 251:: 252 253 [{ 254 "id": 10, 255 "type": "xdp", 256 "tag": "005a3d2123620c8b", 257 "gpl_compatible": true, 258 "run_time_ns": 81632, 259 "run_cnt": 10, 260 "loaded_at": 1506715860, 261 "uid": 0, 262 "bytes_xlated": 528, 263 "jited": true, 264 "bytes_jited": 370, 265 "bytes_memlock": 4096, 266 "map_ids": [10 267 ], 268 "pids": [{ 269 "pid": 1, 270 "comm": "systemd" 271 } 272 ] 273 } 274 ] 275 276| 277| **# bpftool prog dump xlated id 10 file /tmp/t** 278| **$ ls -l /tmp/t** 279 280:: 281 282 -rw------- 1 root root 560 Jul 22 01:42 /tmp/t 283 284**# bpftool prog dump jited tag 005a3d2123620c8b** 285 286:: 287 288 0: push %rbp 289 1: mov %rsp,%rbp 290 2: sub $0x228,%rsp 291 3: sub $0x28,%rbp 292 4: mov %rbx,0x0(%rbp) 293 294| 295| **# mount -t bpf none /sys/fs/bpf/** 296| **# bpftool prog pin id 10 /sys/fs/bpf/prog** 297| **# bpftool prog load ./my_prog.o /sys/fs/bpf/prog2** 298| **# ls -l /sys/fs/bpf/** 299 300:: 301 302 -rw------- 1 root root 0 Jul 22 01:43 prog 303 -rw------- 1 root root 0 Jul 22 01:44 prog2 304 305**# bpftool prog dump jited pinned /sys/fs/bpf/prog opcodes** 306 307:: 308 309 0: push %rbp 310 55 311 1: mov %rsp,%rbp 312 48 89 e5 313 4: sub $0x228,%rsp 314 48 81 ec 28 02 00 00 315 b: sub $0x28,%rbp 316 48 83 ed 28 317 f: mov %rbx,0x0(%rbp) 318 48 89 5d 00 319 320| 321| **# bpftool prog load xdp1_kern.o /sys/fs/bpf/xdp1 type xdp map name rxcnt id 7** 322| **# bpftool prog show pinned /sys/fs/bpf/xdp1** 323 324:: 325 326 9: xdp name xdp_prog1 tag 539ec6ce11b52f98 gpl 327 loaded_at 2018-06-25T16:17:31-0700 uid 0 328 xlated 488B jited 336B memlock 4096B map_ids 7 329 330**# rm /sys/fs/bpf/xdp1** 331 332| 333| **# bpftool prog profile id 337 duration 10 cycles instructions llc_misses** 334 335:: 336 337 51397 run_cnt 338 40176203 cycles (83.05%) 339 42518139 instructions # 1.06 insns per cycle (83.39%) 340 123 llc_misses # 2.89 LLC misses per million insns (83.15%) 341 342| 343| Output below is for the trace logs. 344| Run in separate terminals: 345| **# bpftool prog tracelog** 346| **# bpftool prog load -L -d file.o** 347 348:: 349 350 bpftool-620059 [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5 351 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=6 352 bpftool-620059 [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7 353 bpftool-620059 [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0 354