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** | **visual** | **linum**}] 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*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] 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* } 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/getpeername4** | **cgroup/getpeername6** | 51| **cgroup/getsockname4** | **cgroup/getsockname6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** | 52| **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl** | 53| **cgroup/getsockopt** | **cgroup/setsockopt** | **cgroup/sock_release** | 54| **struct_ops** | **fentry** | **fexit** | **freplace** | **sk_lookup** 55| } 56| *ATTACH_TYPE* := { 57| **sk_msg_verdict** | **sk_skb_verdict** | **sk_skb_stream_verdict** | 58| **sk_skb_stream_parser** | **flow_dissector** 59| } 60| *METRICs* := { 61| **cycles** | **instructions** | **l1d_loads** | **llc_misses** | 62| **itlb_misses** | **dtlb_misses** 63| } 64 65 66DESCRIPTION 67=========== 68 **bpftool prog { show | list }** [*PROG*] 69 Show information about loaded programs. If *PROG* is 70 specified show information only about given programs, 71 otherwise list all programs currently loaded on the system. 72 In case of **tag** or **name**, *PROG* may match several 73 programs which will all be shown. 74 75 Output will start with program ID followed by program type and 76 zero or more named attributes (depending on kernel version). 77 78 Since Linux 5.1 the kernel can collect statistics on BPF 79 programs (such as the total time spent running the program, 80 and the number of times it was run). If available, bpftool 81 shows such statistics. However, the kernel does not collect 82 them by defaults, as it slightly impacts performance on each 83 program run. Activation or deactivation of the feature is 84 performed via the **kernel.bpf_stats_enabled** sysctl knob. 85 86 Since Linux 5.8 bpftool is able to discover information about 87 processes that hold open file descriptors (FDs) against BPF 88 programs. On such kernels bpftool will automatically emit this 89 information as well. 90 91 **bpftool prog dump xlated** *PROG* [{ **file** *FILE* | **opcodes** | **visual** | **linum** }] 92 Dump eBPF instructions of the programs from the kernel. By 93 default, eBPF will be disassembled and printed to standard 94 output in human-readable format. In this case, **opcodes** 95 controls if raw opcodes should be printed as well. 96 97 In case of **tag** or **name**, *PROG* may match several 98 programs which will all be dumped. However, if **file** or 99 **visual** is specified, *PROG* must match a single program. 100 101 If **file** is specified, the binary image will instead be 102 written to *FILE*. 103 104 If **visual** is specified, control flow graph (CFG) will be 105 built instead, and eBPF instructions will be presented with 106 CFG in DOT format, on standard output. 107 108 If the programs have line_info available, the source line will 109 be displayed by default. If **linum** is specified, 110 the filename, line number and line column will also be 111 displayed on top of the source line. 112 113 **bpftool prog dump jited** *PROG* [{ **file** *FILE* | **opcodes** | **linum** }] 114 Dump jited image (host machine code) of the program. 115 116 If *FILE* is specified image will be written to a file, 117 otherwise it will be disassembled and printed to stdout. 118 *PROG* must match a single program when **file** is specified. 119 120 **opcodes** controls if raw opcodes will be printed. 121 122 If the prog has line_info available, the source line will 123 be displayed by default. If **linum** is specified, 124 the filename, line number and line column will also be 125 displayed on top of the source line. 126 127 **bpftool prog pin** *PROG* *FILE* 128 Pin program *PROG* as *FILE*. 129 130 Note: *FILE* must be located in *bpffs* mount. It must not 131 contain a dot character ('.'), which is reserved for future 132 extensions of *bpffs*. 133 134 **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] 135 Load bpf program(s) from binary *OBJ* and pin as *PATH*. 136 **bpftool prog load** pins only the first program from the 137 *OBJ* as *PATH*. **bpftool prog loadall** pins all programs 138 from the *OBJ* under *PATH* directory. 139 **type** is optional, if not specified program type will be 140 inferred from section names. 141 By default bpftool will create new maps as declared in the ELF 142 object being loaded. **map** parameter allows for the reuse 143 of existing maps. It can be specified multiple times, each 144 time for a different map. *IDX* refers to index of the map 145 to be replaced in the ELF file counting from 0, while *NAME* 146 allows to replace a map by name. *MAP* specifies the map to 147 use, referring to it by **id** or through a **pinned** file. 148 If **dev** *NAME* is specified program will be loaded onto 149 given networking device (offload). 150 Optional **pinmaps** argument can be provided to pin all 151 maps under *MAP_DIR* directory. 152 153 Note: *PATH* must be located in *bpffs* mount. It must not 154 contain a dot character ('.'), which is reserved for future 155 extensions of *bpffs*. 156 157 **bpftool prog attach** *PROG* *ATTACH_TYPE* [*MAP*] 158 Attach bpf program *PROG* (with type specified by 159 *ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP* 160 parameter, with the exception of *flow_dissector* which is 161 attached to current networking name space. 162 163 **bpftool prog detach** *PROG* *ATTACH_TYPE* [*MAP*] 164 Detach bpf program *PROG* (with type specified by 165 *ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP* 166 parameter, with the exception of *flow_dissector* which is 167 detached from the current networking name space. 168 169 **bpftool prog tracelog** 170 Dump the trace pipe of the system to the console (stdout). 171 Hit <Ctrl+C> to stop printing. BPF programs can write to this 172 trace pipe at runtime with the **bpf_trace_printk**\ () helper. 173 This should be used only for debugging purposes. For 174 streaming data from BPF programs to user space, one can use 175 perf events (see also **bpftool-map**\ (8)). 176 177 **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*] 178 Run BPF program *PROG* in the kernel testing infrastructure 179 for BPF, meaning that the program works on the data and 180 context provided by the user, and not on actual packets or 181 monitored functions etc. Return value and duration for the 182 test run are printed out to the console. 183 184 Input data is read from the *FILE* passed with **data_in**. 185 If this *FILE* is "**-**", input data is read from standard 186 input. Input context, if any, is read from *FILE* passed with 187 **ctx_in**. Again, "**-**" can be used to read from standard 188 input, but only if standard input is not already in use for 189 input data. If a *FILE* is passed with **data_out**, output 190 data is written to that file. Similarly, output context is 191 written to the *FILE* passed with **ctx_out**. For both 192 output flows, "**-**" can be used to print to the standard 193 output (as plain text, or JSON if relevant option was 194 passed). If output keywords are omitted, output data and 195 context are discarded. Keywords **data_size_out** and 196 **ctx_size_out** are used to pass the size (in bytes) for the 197 output buffers to the kernel, although the default of 32 kB 198 should be more than enough for most cases. 199 200 Keyword **repeat** is used to indicate the number of 201 consecutive runs to perform. Note that output data and 202 context printed to files correspond to the last of those 203 runs. The duration printed out at the end of the runs is an 204 average over all runs performed by the command. 205 206 Not all program types support test run. Among those which do, 207 not all of them can take the **ctx_in**/**ctx_out** 208 arguments. bpftool does not perform checks on program types. 209 210 **bpftool prog profile** *PROG* [**duration** *DURATION*] *METRICs* 211 Profile *METRICs* for bpf program *PROG* for *DURATION* 212 seconds or until user hits <Ctrl+C>. *DURATION* is optional. 213 If *DURATION* is not specified, the profiling will run up to 214 **UINT_MAX** seconds. 215 216 **bpftool prog help** 217 Print short help message. 218 219OPTIONS 220======= 221 .. include:: common_options.rst 222 223 -f, --bpffs 224 When showing BPF programs, show file names of pinned 225 programs. 226 227 -m, --mapcompat 228 Allow loading maps with unknown map definitions. 229 230 -n, --nomount 231 Do not automatically attempt to mount any virtual file system 232 (such as tracefs or BPF virtual file system) when necessary. 233 234 -L, --use-loader 235 Load program as a "loader" program. This is useful to debug 236 the generation of such programs. When this option is in 237 use, bpftool attempts to load the programs from the object 238 file into the kernel, but does not pin them (therefore, the 239 *PATH* must not be provided). 240 241 When combined with the **-d**\ \|\ **--debug** option, 242 additional debug messages are generated, and the execution 243 of the loader program will use the **bpf_trace_printk**\ () 244 helper to log each step of loading BTF, creating the maps, 245 and loading the programs (see **bpftool prog tracelog** as 246 a way to dump those messages). 247 248EXAMPLES 249======== 250**# bpftool prog show** 251 252:: 253 254 10: xdp name some_prog tag 005a3d2123620c8b gpl run_time_ns 81632 run_cnt 10 255 loaded_at 2017-09-29T20:11:00+0000 uid 0 256 xlated 528B jited 370B memlock 4096B map_ids 10 257 pids systemd(1) 258 259**# bpftool --json --pretty prog show** 260 261:: 262 263 [{ 264 "id": 10, 265 "type": "xdp", 266 "tag": "005a3d2123620c8b", 267 "gpl_compatible": true, 268 "run_time_ns": 81632, 269 "run_cnt": 10, 270 "loaded_at": 1506715860, 271 "uid": 0, 272 "bytes_xlated": 528, 273 "jited": true, 274 "bytes_jited": 370, 275 "bytes_memlock": 4096, 276 "map_ids": [10 277 ], 278 "pids": [{ 279 "pid": 1, 280 "comm": "systemd" 281 } 282 ] 283 } 284 ] 285 286| 287| **# bpftool prog dump xlated id 10 file /tmp/t** 288| **$ ls -l /tmp/t** 289 290:: 291 292 -rw------- 1 root root 560 Jul 22 01:42 /tmp/t 293 294**# bpftool prog dump jited tag 005a3d2123620c8b** 295 296:: 297 298 0: push %rbp 299 1: mov %rsp,%rbp 300 2: sub $0x228,%rsp 301 3: sub $0x28,%rbp 302 4: mov %rbx,0x0(%rbp) 303 304| 305| **# mount -t bpf none /sys/fs/bpf/** 306| **# bpftool prog pin id 10 /sys/fs/bpf/prog** 307| **# bpftool prog load ./my_prog.o /sys/fs/bpf/prog2** 308| **# ls -l /sys/fs/bpf/** 309 310:: 311 312 -rw------- 1 root root 0 Jul 22 01:43 prog 313 -rw------- 1 root root 0 Jul 22 01:44 prog2 314 315**# bpftool prog dump jited pinned /sys/fs/bpf/prog opcodes** 316 317:: 318 319 0: push %rbp 320 55 321 1: mov %rsp,%rbp 322 48 89 e5 323 4: sub $0x228,%rsp 324 48 81 ec 28 02 00 00 325 b: sub $0x28,%rbp 326 48 83 ed 28 327 f: mov %rbx,0x0(%rbp) 328 48 89 5d 00 329 330| 331| **# bpftool prog load xdp1_kern.o /sys/fs/bpf/xdp1 type xdp map name rxcnt id 7** 332| **# bpftool prog show pinned /sys/fs/bpf/xdp1** 333 334:: 335 336 9: xdp name xdp_prog1 tag 539ec6ce11b52f98 gpl 337 loaded_at 2018-06-25T16:17:31-0700 uid 0 338 xlated 488B jited 336B memlock 4096B map_ids 7 339 340**# rm /sys/fs/bpf/xdp1** 341 342| 343| **# bpftool prog profile id 337 duration 10 cycles instructions llc_misses** 344 345:: 346 347 51397 run_cnt 348 40176203 cycles (83.05%) 349 42518139 instructions # 1.06 insns per cycle (83.39%) 350 123 llc_misses # 2.89 LLC misses per million insns (83.15%) 351 352| 353| Output below is for the trace logs. 354| Run in separate terminals: 355| **# bpftool prog tracelog** 356| **# bpftool prog load -L -d file.o** 357 358:: 359 360 bpftool-620059 [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5 361 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=6 362 bpftool-620059 [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7 363 bpftool-620059 [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0 364