| // SPDX-License-Identifier: GPL-2.0 | 
 | #include <errno.h> | 
 | #include <stdlib.h> | 
 | #include <bpf/bpf.h> | 
 | #include <bpf/btf.h> | 
 | #include <bpf/libbpf.h> | 
 | #include <linux/btf.h> | 
 | #include <linux/err.h> | 
 | #include "bpf-event.h" | 
 | #include "debug.h" | 
 | #include "dso.h" | 
 | #include "symbol.h" | 
 | #include "machine.h" | 
 | #include "env.h" | 
 | #include "session.h" | 
 | #include "map.h" | 
 | #include "evlist.h" | 
 | #include "record.h" | 
 | #include "util/synthetic-events.h" | 
 |  | 
 | #define ptr_to_u64(ptr)    ((__u64)(unsigned long)(ptr)) | 
 |  | 
 | static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len) | 
 | { | 
 | 	int ret = 0; | 
 | 	size_t i; | 
 |  | 
 | 	for (i = 0; i < len; i++) | 
 | 		ret += snprintf(buf + ret, size - ret, "%02x", data[i]); | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int machine__process_bpf_event_load(struct machine *machine, | 
 | 					   union perf_event *event, | 
 | 					   struct perf_sample *sample __maybe_unused) | 
 | { | 
 | 	struct bpf_prog_info_linear *info_linear; | 
 | 	struct bpf_prog_info_node *info_node; | 
 | 	struct perf_env *env = machine->env; | 
 | 	int id = event->bpf.id; | 
 | 	unsigned int i; | 
 |  | 
 | 	/* perf-record, no need to handle bpf-event */ | 
 | 	if (env == NULL) | 
 | 		return 0; | 
 |  | 
 | 	info_node = perf_env__find_bpf_prog_info(env, id); | 
 | 	if (!info_node) | 
 | 		return 0; | 
 | 	info_linear = info_node->info_linear; | 
 |  | 
 | 	for (i = 0; i < info_linear->info.nr_jited_ksyms; i++) { | 
 | 		u64 *addrs = (u64 *)(uintptr_t)(info_linear->info.jited_ksyms); | 
 | 		u64 addr = addrs[i]; | 
 | 		struct map *map; | 
 |  | 
 | 		map = map_groups__find(&machine->kmaps, addr); | 
 |  | 
 | 		if (map) { | 
 | 			map->dso->binary_type = DSO_BINARY_TYPE__BPF_PROG_INFO; | 
 | 			map->dso->bpf_prog.id = id; | 
 | 			map->dso->bpf_prog.sub_id = i; | 
 | 			map->dso->bpf_prog.env = env; | 
 | 		} | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | int machine__process_bpf(struct machine *machine, union perf_event *event, | 
 | 			 struct perf_sample *sample) | 
 | { | 
 | 	if (dump_trace) | 
 | 		perf_event__fprintf_bpf(event, stdout); | 
 |  | 
 | 	switch (event->bpf.type) { | 
 | 	case PERF_BPF_EVENT_PROG_LOAD: | 
 | 		return machine__process_bpf_event_load(machine, event, sample); | 
 |  | 
 | 	case PERF_BPF_EVENT_PROG_UNLOAD: | 
 | 		/* | 
 | 		 * Do not free bpf_prog_info and btf of the program here, | 
 | 		 * as annotation still need them. They will be freed at | 
 | 		 * the end of the session. | 
 | 		 */ | 
 | 		break; | 
 | 	default: | 
 | 		pr_debug("unexpected bpf event type of %d\n", event->bpf.type); | 
 | 		break; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int perf_env__fetch_btf(struct perf_env *env, | 
 | 			       u32 btf_id, | 
 | 			       struct btf *btf) | 
 | { | 
 | 	struct btf_node *node; | 
 | 	u32 data_size; | 
 | 	const void *data; | 
 |  | 
 | 	data = btf__get_raw_data(btf, &data_size); | 
 |  | 
 | 	node = malloc(data_size + sizeof(struct btf_node)); | 
 | 	if (!node) | 
 | 		return -1; | 
 |  | 
 | 	node->id = btf_id; | 
 | 	node->data_size = data_size; | 
 | 	memcpy(node->data, data, data_size); | 
 |  | 
 | 	if (!perf_env__insert_btf(env, node)) { | 
 | 		/* Insertion failed because of a duplicate. */ | 
 | 		free(node); | 
 | 		return -1; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int synthesize_bpf_prog_name(char *buf, int size, | 
 | 				    struct bpf_prog_info *info, | 
 | 				    struct btf *btf, | 
 | 				    u32 sub_id) | 
 | { | 
 | 	u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags); | 
 | 	void *func_infos = (void *)(uintptr_t)(info->func_info); | 
 | 	u32 sub_prog_cnt = info->nr_jited_ksyms; | 
 | 	const struct bpf_func_info *finfo; | 
 | 	const char *short_name = NULL; | 
 | 	const struct btf_type *t; | 
 | 	int name_len; | 
 |  | 
 | 	name_len = snprintf(buf, size, "bpf_prog_"); | 
 | 	name_len += snprintf_hex(buf + name_len, size - name_len, | 
 | 				 prog_tags[sub_id], BPF_TAG_SIZE); | 
 | 	if (btf) { | 
 | 		finfo = func_infos + sub_id * info->func_info_rec_size; | 
 | 		t = btf__type_by_id(btf, finfo->type_id); | 
 | 		short_name = btf__name_by_offset(btf, t->name_off); | 
 | 	} else if (sub_id == 0 && sub_prog_cnt == 1) { | 
 | 		/* no subprog */ | 
 | 		if (info->name[0]) | 
 | 			short_name = info->name; | 
 | 	} else | 
 | 		short_name = "F"; | 
 | 	if (short_name) | 
 | 		name_len += snprintf(buf + name_len, size - name_len, | 
 | 				     "_%s", short_name); | 
 | 	return name_len; | 
 | } | 
 |  | 
 | /* | 
 |  * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf | 
 |  * program. One PERF_RECORD_BPF_EVENT is generated for the program. And | 
 |  * one PERF_RECORD_KSYMBOL is generated for each sub program. | 
 |  * | 
 |  * Returns: | 
 |  *    0 for success; | 
 |  *   -1 for failures; | 
 |  *   -2 for lack of kernel support. | 
 |  */ | 
 | static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, | 
 | 					       perf_event__handler_t process, | 
 | 					       struct machine *machine, | 
 | 					       int fd, | 
 | 					       union perf_event *event, | 
 | 					       struct record_opts *opts) | 
 | { | 
 | 	struct perf_record_ksymbol *ksymbol_event = &event->ksymbol; | 
 | 	struct perf_record_bpf_event *bpf_event = &event->bpf; | 
 | 	struct bpf_prog_info_linear *info_linear; | 
 | 	struct perf_tool *tool = session->tool; | 
 | 	struct bpf_prog_info_node *info_node; | 
 | 	struct bpf_prog_info *info; | 
 | 	struct btf *btf = NULL; | 
 | 	struct perf_env *env; | 
 | 	u32 sub_prog_cnt, i; | 
 | 	int err = 0; | 
 | 	u64 arrays; | 
 |  | 
 | 	/* | 
 | 	 * for perf-record and perf-report use header.env; | 
 | 	 * otherwise, use global perf_env. | 
 | 	 */ | 
 | 	env = session->data ? &session->header.env : &perf_env; | 
 |  | 
 | 	arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; | 
 |  | 
 | 	info_linear = bpf_program__get_prog_info_linear(fd, arrays); | 
 | 	if (IS_ERR_OR_NULL(info_linear)) { | 
 | 		info_linear = NULL; | 
 | 		pr_debug("%s: failed to get BPF program info. aborting\n", __func__); | 
 | 		return -1; | 
 | 	} | 
 |  | 
 | 	if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) { | 
 | 		pr_debug("%s: the kernel is too old, aborting\n", __func__); | 
 | 		return -2; | 
 | 	} | 
 |  | 
 | 	info = &info_linear->info; | 
 |  | 
 | 	/* number of ksyms, func_lengths, and tags should match */ | 
 | 	sub_prog_cnt = info->nr_jited_ksyms; | 
 | 	if (sub_prog_cnt != info->nr_prog_tags || | 
 | 	    sub_prog_cnt != info->nr_jited_func_lens) | 
 | 		return -1; | 
 |  | 
 | 	/* check BTF func info support */ | 
 | 	if (info->btf_id && info->nr_func_info && info->func_info_rec_size) { | 
 | 		/* btf func info number should be same as sub_prog_cnt */ | 
 | 		if (sub_prog_cnt != info->nr_func_info) { | 
 | 			pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__); | 
 | 			err = -1; | 
 | 			goto out; | 
 | 		} | 
 | 		if (btf__get_from_id(info->btf_id, &btf)) { | 
 | 			pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id); | 
 | 			err = -1; | 
 | 			btf = NULL; | 
 | 			goto out; | 
 | 		} | 
 | 		perf_env__fetch_btf(env, info->btf_id, btf); | 
 | 	} | 
 |  | 
 | 	/* Synthesize PERF_RECORD_KSYMBOL */ | 
 | 	for (i = 0; i < sub_prog_cnt; i++) { | 
 | 		__u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens); | 
 | 		__u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms); | 
 | 		int name_len; | 
 |  | 
 | 		*ksymbol_event = (struct perf_record_ksymbol) { | 
 | 			.header = { | 
 | 				.type = PERF_RECORD_KSYMBOL, | 
 | 				.size = offsetof(struct perf_record_ksymbol, name), | 
 | 			}, | 
 | 			.addr = prog_addrs[i], | 
 | 			.len = prog_lens[i], | 
 | 			.ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF, | 
 | 			.flags = 0, | 
 | 		}; | 
 |  | 
 | 		name_len = synthesize_bpf_prog_name(ksymbol_event->name, | 
 | 						    KSYM_NAME_LEN, info, btf, i); | 
 | 		ksymbol_event->header.size += PERF_ALIGN(name_len + 1, | 
 | 							 sizeof(u64)); | 
 |  | 
 | 		memset((void *)event + event->header.size, 0, machine->id_hdr_size); | 
 | 		event->header.size += machine->id_hdr_size; | 
 | 		err = perf_tool__process_synth_event(tool, event, | 
 | 						     machine, process); | 
 | 	} | 
 |  | 
 | 	if (!opts->no_bpf_event) { | 
 | 		/* Synthesize PERF_RECORD_BPF_EVENT */ | 
 | 		*bpf_event = (struct perf_record_bpf_event) { | 
 | 			.header = { | 
 | 				.type = PERF_RECORD_BPF_EVENT, | 
 | 				.size = sizeof(struct perf_record_bpf_event), | 
 | 			}, | 
 | 			.type = PERF_BPF_EVENT_PROG_LOAD, | 
 | 			.flags = 0, | 
 | 			.id = info->id, | 
 | 		}; | 
 | 		memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE); | 
 | 		memset((void *)event + event->header.size, 0, machine->id_hdr_size); | 
 | 		event->header.size += machine->id_hdr_size; | 
 |  | 
 | 		/* save bpf_prog_info to env */ | 
 | 		info_node = malloc(sizeof(struct bpf_prog_info_node)); | 
 | 		if (!info_node) { | 
 | 			err = -1; | 
 | 			goto out; | 
 | 		} | 
 |  | 
 | 		info_node->info_linear = info_linear; | 
 | 		perf_env__insert_bpf_prog_info(env, info_node); | 
 | 		info_linear = NULL; | 
 |  | 
 | 		/* | 
 | 		 * process after saving bpf_prog_info to env, so that | 
 | 		 * required information is ready for look up | 
 | 		 */ | 
 | 		err = perf_tool__process_synth_event(tool, event, | 
 | 						     machine, process); | 
 | 	} | 
 |  | 
 | out: | 
 | 	free(info_linear); | 
 | 	free(btf); | 
 | 	return err ? -1 : 0; | 
 | } | 
 |  | 
 | int perf_event__synthesize_bpf_events(struct perf_session *session, | 
 | 				      perf_event__handler_t process, | 
 | 				      struct machine *machine, | 
 | 				      struct record_opts *opts) | 
 | { | 
 | 	union perf_event *event; | 
 | 	__u32 id = 0; | 
 | 	int err; | 
 | 	int fd; | 
 |  | 
 | 	event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size); | 
 | 	if (!event) | 
 | 		return -1; | 
 | 	while (true) { | 
 | 		err = bpf_prog_get_next_id(id, &id); | 
 | 		if (err) { | 
 | 			if (errno == ENOENT) { | 
 | 				err = 0; | 
 | 				break; | 
 | 			} | 
 | 			pr_debug("%s: can't get next program: %s%s\n", | 
 | 				 __func__, strerror(errno), | 
 | 				 errno == EINVAL ? " -- kernel too old?" : ""); | 
 | 			/* don't report error on old kernel or EPERM  */ | 
 | 			err = (errno == EINVAL || errno == EPERM) ? 0 : -1; | 
 | 			break; | 
 | 		} | 
 | 		fd = bpf_prog_get_fd_by_id(id); | 
 | 		if (fd < 0) { | 
 | 			pr_debug("%s: failed to get fd for prog_id %u\n", | 
 | 				 __func__, id); | 
 | 			continue; | 
 | 		} | 
 |  | 
 | 		err = perf_event__synthesize_one_bpf_prog(session, process, | 
 | 							  machine, fd, | 
 | 							  event, opts); | 
 | 		close(fd); | 
 | 		if (err) { | 
 | 			/* do not return error for old kernel */ | 
 | 			if (err == -2) | 
 | 				err = 0; | 
 | 			break; | 
 | 		} | 
 | 	} | 
 | 	free(event); | 
 | 	return err; | 
 | } | 
 |  | 
 | static void perf_env__add_bpf_info(struct perf_env *env, u32 id) | 
 | { | 
 | 	struct bpf_prog_info_linear *info_linear; | 
 | 	struct bpf_prog_info_node *info_node; | 
 | 	struct btf *btf = NULL; | 
 | 	u64 arrays; | 
 | 	u32 btf_id; | 
 | 	int fd; | 
 |  | 
 | 	fd = bpf_prog_get_fd_by_id(id); | 
 | 	if (fd < 0) | 
 | 		return; | 
 |  | 
 | 	arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; | 
 | 	arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; | 
 |  | 
 | 	info_linear = bpf_program__get_prog_info_linear(fd, arrays); | 
 | 	if (IS_ERR_OR_NULL(info_linear)) { | 
 | 		pr_debug("%s: failed to get BPF program info. aborting\n", __func__); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	btf_id = info_linear->info.btf_id; | 
 |  | 
 | 	info_node = malloc(sizeof(struct bpf_prog_info_node)); | 
 | 	if (info_node) { | 
 | 		info_node->info_linear = info_linear; | 
 | 		perf_env__insert_bpf_prog_info(env, info_node); | 
 | 	} else | 
 | 		free(info_linear); | 
 |  | 
 | 	if (btf_id == 0) | 
 | 		goto out; | 
 |  | 
 | 	if (btf__get_from_id(btf_id, &btf)) { | 
 | 		pr_debug("%s: failed to get BTF of id %u, aborting\n", | 
 | 			 __func__, btf_id); | 
 | 		goto out; | 
 | 	} | 
 | 	perf_env__fetch_btf(env, btf_id, btf); | 
 |  | 
 | out: | 
 | 	free(btf); | 
 | 	close(fd); | 
 | } | 
 |  | 
 | static int bpf_event__sb_cb(union perf_event *event, void *data) | 
 | { | 
 | 	struct perf_env *env = data; | 
 |  | 
 | 	if (event->header.type != PERF_RECORD_BPF_EVENT) | 
 | 		return -1; | 
 |  | 
 | 	switch (event->bpf.type) { | 
 | 	case PERF_BPF_EVENT_PROG_LOAD: | 
 | 		perf_env__add_bpf_info(env, event->bpf.id); | 
 |  | 
 | 	case PERF_BPF_EVENT_PROG_UNLOAD: | 
 | 		/* | 
 | 		 * Do not free bpf_prog_info and btf of the program here, | 
 | 		 * as annotation still need them. They will be freed at | 
 | 		 * the end of the session. | 
 | 		 */ | 
 | 		break; | 
 | 	default: | 
 | 		pr_debug("unexpected bpf event type of %d\n", event->bpf.type); | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env) | 
 | { | 
 | 	struct perf_event_attr attr = { | 
 | 		.type	          = PERF_TYPE_SOFTWARE, | 
 | 		.config           = PERF_COUNT_SW_DUMMY, | 
 | 		.sample_id_all    = 1, | 
 | 		.watermark        = 1, | 
 | 		.bpf_event        = 1, | 
 | 		.size	   = sizeof(attr), /* to capture ABI version */ | 
 | 	}; | 
 |  | 
 | 	/* | 
 | 	 * Older gcc versions don't support designated initializers, like above, | 
 | 	 * for unnamed union members, such as the following: | 
 | 	 */ | 
 | 	attr.wakeup_watermark = 1; | 
 |  | 
 | 	return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env); | 
 | } | 
 |  | 
 | void __bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, | 
 | 				      struct perf_env *env, | 
 | 				      FILE *fp) | 
 | { | 
 | 	__u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens); | 
 | 	__u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms); | 
 | 	char name[KSYM_NAME_LEN]; | 
 | 	struct btf *btf = NULL; | 
 | 	u32 sub_prog_cnt, i; | 
 |  | 
 | 	sub_prog_cnt = info->nr_jited_ksyms; | 
 | 	if (sub_prog_cnt != info->nr_prog_tags || | 
 | 	    sub_prog_cnt != info->nr_jited_func_lens) | 
 | 		return; | 
 |  | 
 | 	if (info->btf_id) { | 
 | 		struct btf_node *node; | 
 |  | 
 | 		node = __perf_env__find_btf(env, info->btf_id); | 
 | 		if (node) | 
 | 			btf = btf__new((__u8 *)(node->data), | 
 | 				       node->data_size); | 
 | 	} | 
 |  | 
 | 	if (sub_prog_cnt == 1) { | 
 | 		synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0); | 
 | 		fprintf(fp, "# bpf_prog_info %u: %s addr 0x%llx size %u\n", | 
 | 			info->id, name, prog_addrs[0], prog_lens[0]); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	fprintf(fp, "# bpf_prog_info %u:\n", info->id); | 
 | 	for (i = 0; i < sub_prog_cnt; i++) { | 
 | 		synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i); | 
 |  | 
 | 		fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n", | 
 | 			i, name, prog_addrs[i], prog_lens[i]); | 
 | 	} | 
 | out: | 
 | 	btf__free(btf); | 
 | } |