1 // SPDX-License-Identifier: GPL-2.0
6 #include <bpf/libbpf.h>
19 #include "util/synthetic-events.h"
21 #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
23 static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len)
28 for (i = 0; i < len; i++)
29 ret += snprintf(buf + ret, size - ret, "%02x", data[i]);
33 static int machine__process_bpf_event_load(struct machine *machine,
34 union perf_event *event,
35 struct perf_sample *sample __maybe_unused)
37 struct bpf_prog_info_linear *info_linear;
38 struct bpf_prog_info_node *info_node;
39 struct perf_env *env = machine->env;
40 int id = event->bpf.id;
43 /* perf-record, no need to handle bpf-event */
47 info_node = perf_env__find_bpf_prog_info(env, id);
50 info_linear = info_node->info_linear;
52 for (i = 0; i < info_linear->info.nr_jited_ksyms; i++) {
53 u64 *addrs = (u64 *)(uintptr_t)(info_linear->info.jited_ksyms);
55 struct map *map = maps__find(&machine->kmaps, addr);
58 map->dso->binary_type = DSO_BINARY_TYPE__BPF_PROG_INFO;
59 map->dso->bpf_prog.id = id;
60 map->dso->bpf_prog.sub_id = i;
61 map->dso->bpf_prog.env = env;
67 int machine__process_bpf(struct machine *machine, union perf_event *event,
68 struct perf_sample *sample)
71 perf_event__fprintf_bpf(event, stdout);
73 switch (event->bpf.type) {
74 case PERF_BPF_EVENT_PROG_LOAD:
75 return machine__process_bpf_event_load(machine, event, sample);
77 case PERF_BPF_EVENT_PROG_UNLOAD:
79 * Do not free bpf_prog_info and btf of the program here,
80 * as annotation still need them. They will be freed at
81 * the end of the session.
85 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
91 static int perf_env__fetch_btf(struct perf_env *env,
95 struct btf_node *node;
99 data = btf__get_raw_data(btf, &data_size);
101 node = malloc(data_size + sizeof(struct btf_node));
106 node->data_size = data_size;
107 memcpy(node->data, data, data_size);
109 perf_env__insert_btf(env, node);
113 static int synthesize_bpf_prog_name(char *buf, int size,
114 struct bpf_prog_info *info,
118 u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
119 void *func_infos = (void *)(uintptr_t)(info->func_info);
120 u32 sub_prog_cnt = info->nr_jited_ksyms;
121 const struct bpf_func_info *finfo;
122 const char *short_name = NULL;
123 const struct btf_type *t;
126 name_len = snprintf(buf, size, "bpf_prog_");
127 name_len += snprintf_hex(buf + name_len, size - name_len,
128 prog_tags[sub_id], BPF_TAG_SIZE);
130 finfo = func_infos + sub_id * info->func_info_rec_size;
131 t = btf__type_by_id(btf, finfo->type_id);
132 short_name = btf__name_by_offset(btf, t->name_off);
133 } else if (sub_id == 0 && sub_prog_cnt == 1) {
136 short_name = info->name;
140 name_len += snprintf(buf + name_len, size - name_len,
146 * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
147 * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
148 * one PERF_RECORD_KSYMBOL is generated for each sub program.
153 * -2 for lack of kernel support.
155 static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
156 perf_event__handler_t process,
157 struct machine *machine,
159 union perf_event *event,
160 struct record_opts *opts)
162 struct perf_record_ksymbol *ksymbol_event = &event->ksymbol;
163 struct perf_record_bpf_event *bpf_event = &event->bpf;
164 struct bpf_prog_info_linear *info_linear;
165 struct perf_tool *tool = session->tool;
166 struct bpf_prog_info_node *info_node;
167 struct bpf_prog_info *info;
168 struct btf *btf = NULL;
169 struct perf_env *env;
175 * for perf-record and perf-report use header.env;
176 * otherwise, use global perf_env.
178 env = session->data ? &session->header.env : &perf_env;
180 arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
181 arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
182 arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
183 arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
184 arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
185 arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
186 arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
188 info_linear = bpf_program__get_prog_info_linear(fd, arrays);
189 if (IS_ERR_OR_NULL(info_linear)) {
191 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
195 if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) {
196 pr_debug("%s: the kernel is too old, aborting\n", __func__);
200 info = &info_linear->info;
202 /* number of ksyms, func_lengths, and tags should match */
203 sub_prog_cnt = info->nr_jited_ksyms;
204 if (sub_prog_cnt != info->nr_prog_tags ||
205 sub_prog_cnt != info->nr_jited_func_lens)
208 /* check BTF func info support */
209 if (info->btf_id && info->nr_func_info && info->func_info_rec_size) {
210 /* btf func info number should be same as sub_prog_cnt */
211 if (sub_prog_cnt != info->nr_func_info) {
212 pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__);
216 if (btf__get_from_id(info->btf_id, &btf)) {
217 pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id);
222 perf_env__fetch_btf(env, info->btf_id, btf);
225 /* Synthesize PERF_RECORD_KSYMBOL */
226 for (i = 0; i < sub_prog_cnt; i++) {
227 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
228 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
231 *ksymbol_event = (struct perf_record_ksymbol) {
233 .type = PERF_RECORD_KSYMBOL,
234 .size = offsetof(struct perf_record_ksymbol, name),
236 .addr = prog_addrs[i],
238 .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
242 name_len = synthesize_bpf_prog_name(ksymbol_event->name,
243 KSYM_NAME_LEN, info, btf, i);
244 ksymbol_event->header.size += PERF_ALIGN(name_len + 1,
247 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
248 event->header.size += machine->id_hdr_size;
249 err = perf_tool__process_synth_event(tool, event,
253 if (!opts->no_bpf_event) {
254 /* Synthesize PERF_RECORD_BPF_EVENT */
255 *bpf_event = (struct perf_record_bpf_event) {
257 .type = PERF_RECORD_BPF_EVENT,
258 .size = sizeof(struct perf_record_bpf_event),
260 .type = PERF_BPF_EVENT_PROG_LOAD,
264 memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
265 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
266 event->header.size += machine->id_hdr_size;
268 /* save bpf_prog_info to env */
269 info_node = malloc(sizeof(struct bpf_prog_info_node));
275 info_node->info_linear = info_linear;
276 perf_env__insert_bpf_prog_info(env, info_node);
280 * process after saving bpf_prog_info to env, so that
281 * required information is ready for look up
283 err = perf_tool__process_synth_event(tool, event,
293 int perf_event__synthesize_bpf_events(struct perf_session *session,
294 perf_event__handler_t process,
295 struct machine *machine,
296 struct record_opts *opts)
298 union perf_event *event;
303 event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size);
307 err = bpf_prog_get_next_id(id, &id);
309 if (errno == ENOENT) {
313 pr_debug("%s: can't get next program: %s%s\n",
314 __func__, strerror(errno),
315 errno == EINVAL ? " -- kernel too old?" : "");
316 /* don't report error on old kernel or EPERM */
317 err = (errno == EINVAL || errno == EPERM) ? 0 : -1;
320 fd = bpf_prog_get_fd_by_id(id);
322 pr_debug("%s: failed to get fd for prog_id %u\n",
327 err = perf_event__synthesize_one_bpf_prog(session, process,
332 /* do not return error for old kernel */
342 static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
344 struct bpf_prog_info_linear *info_linear;
345 struct bpf_prog_info_node *info_node;
346 struct btf *btf = NULL;
351 fd = bpf_prog_get_fd_by_id(id);
355 arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
356 arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
357 arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
358 arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
359 arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
360 arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
361 arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
363 info_linear = bpf_program__get_prog_info_linear(fd, arrays);
364 if (IS_ERR_OR_NULL(info_linear)) {
365 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
369 btf_id = info_linear->info.btf_id;
371 info_node = malloc(sizeof(struct bpf_prog_info_node));
373 info_node->info_linear = info_linear;
374 perf_env__insert_bpf_prog_info(env, info_node);
381 if (btf__get_from_id(btf_id, &btf)) {
382 pr_debug("%s: failed to get BTF of id %u, aborting\n",
386 perf_env__fetch_btf(env, btf_id, btf);
393 static int bpf_event__sb_cb(union perf_event *event, void *data)
395 struct perf_env *env = data;
397 if (event->header.type != PERF_RECORD_BPF_EVENT)
400 switch (event->bpf.type) {
401 case PERF_BPF_EVENT_PROG_LOAD:
402 perf_env__add_bpf_info(env, event->bpf.id);
404 case PERF_BPF_EVENT_PROG_UNLOAD:
406 * Do not free bpf_prog_info and btf of the program here,
407 * as annotation still need them. They will be freed at
408 * the end of the session.
412 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
419 int bpf_event__add_sb_event(struct evlist **evlist,
420 struct perf_env *env)
422 struct perf_event_attr attr = {
423 .type = PERF_TYPE_SOFTWARE,
424 .config = PERF_COUNT_SW_DUMMY,
428 .size = sizeof(attr), /* to capture ABI version */
432 * Older gcc versions don't support designated initializers, like above,
433 * for unnamed union members, such as the following:
435 attr.wakeup_watermark = 1;
437 return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env);
440 void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
441 struct perf_env *env,
444 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
445 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
446 char name[KSYM_NAME_LEN];
447 struct btf *btf = NULL;
450 sub_prog_cnt = info->nr_jited_ksyms;
451 if (sub_prog_cnt != info->nr_prog_tags ||
452 sub_prog_cnt != info->nr_jited_func_lens)
456 struct btf_node *node;
458 node = perf_env__find_btf(env, info->btf_id);
460 btf = btf__new((__u8 *)(node->data),
464 if (sub_prog_cnt == 1) {
465 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0);
466 fprintf(fp, "# bpf_prog_info %u: %s addr 0x%llx size %u\n",
467 info->id, name, prog_addrs[0], prog_lens[0]);
471 fprintf(fp, "# bpf_prog_info %u:\n", info->id);
472 for (i = 0; i < sub_prog_cnt; i++) {
473 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i);
475 fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n",
476 i, name, prog_addrs[i], prog_lens[i]);