diff options
Diffstat (limited to 'tools/perf/util/bpf-event.c')
-rw-r--r-- | tools/perf/util/bpf-event.c | 501 |
1 files changed, 452 insertions, 49 deletions
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 3742511a08d1..5b6d3e899e11 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -1,15 +1,24 @@ // SPDX-License-Identifier: GPL-2.0 #include <errno.h> +#include <stddef.h> +#include <stdint.h> +#include <stdio.h> #include <stdlib.h> +#include <string.h> #include <bpf/bpf.h> #include <bpf/btf.h> #include <bpf/libbpf.h> +#include <linux/bpf.h> #include <linux/btf.h> #include <linux/err.h> +#include <linux/perf_event.h> #include <linux/string.h> +#include <linux/zalloc.h> #include <internal/lib.h> +#include <perf/event.h> #include <symbol/kallsyms.h> #include "bpf-event.h" +#include "bpf-utils.h" #include "debug.h" #include "dso.h" #include "symbol.h" @@ -21,8 +30,6 @@ #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; @@ -37,9 +44,9 @@ 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; + struct perf_bpil *info_linear; int id = event->bpf.id; unsigned int i; @@ -55,13 +62,16 @@ static int machine__process_bpf_event_load(struct machine *machine, 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 = maps__find(&machine->kmaps, addr); + struct map *map = maps__find(machine__kernel_maps(machine), 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; + struct dso *dso = map__dso(map); + + dso__set_binary_type(dso, DSO_BINARY_TYPE__BPF_PROG_INFO); + dso__bpf_prog(dso)->id = id; + dso__bpf_prog(dso)->sub_id = i; + dso__bpf_prog(dso)->env = env; + map__put(map); } } return 0; @@ -99,7 +109,7 @@ static int perf_env__fetch_btf(struct perf_env *env, u32 data_size; const void *data; - data = btf__get_raw_data(btf, &data_size); + data = btf__raw_data(btf, &data_size); node = malloc(data_size + sizeof(struct btf_node)); if (!node) @@ -109,7 +119,11 @@ static int perf_env__fetch_btf(struct perf_env *env, node->data_size = data_size; memcpy(node->data, data, data_size); - perf_env__insert_btf(env, node); + if (!perf_env__insert_btf(env, node)) { + /* Insertion failed because of a duplicate. */ + free(node); + return -1; + } return 0; } @@ -145,6 +159,362 @@ static int synthesize_bpf_prog_name(char *buf, int size, return name_len; } +#ifdef HAVE_LIBBPF_STRINGS_SUPPORT + +#define BPF_METADATA_PREFIX "bpf_metadata_" +#define BPF_METADATA_PREFIX_LEN (sizeof(BPF_METADATA_PREFIX) - 1) + +static bool name_has_bpf_metadata_prefix(const char **s) +{ + if (strncmp(*s, BPF_METADATA_PREFIX, BPF_METADATA_PREFIX_LEN) != 0) + return false; + *s += BPF_METADATA_PREFIX_LEN; + return true; +} + +struct bpf_metadata_map { + struct btf *btf; + const struct btf_type *datasec; + void *rodata; + size_t rodata_size; + unsigned int num_vars; +}; + +static int bpf_metadata_read_map_data(__u32 map_id, struct bpf_metadata_map *map) +{ + int map_fd; + struct bpf_map_info map_info; + __u32 map_info_len; + int key; + struct btf *btf; + const struct btf_type *datasec; + struct btf_var_secinfo *vsi; + unsigned int vlen, vars; + void *rodata; + + map_fd = bpf_map_get_fd_by_id(map_id); + if (map_fd < 0) + return -1; + + memset(&map_info, 0, sizeof(map_info)); + map_info_len = sizeof(map_info); + if (bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len) < 0) + goto out_close; + + /* If it's not an .rodata map, don't bother. */ + if (map_info.type != BPF_MAP_TYPE_ARRAY || + map_info.key_size != sizeof(int) || + map_info.max_entries != 1 || + !map_info.btf_value_type_id || + !strstr(map_info.name, ".rodata")) { + goto out_close; + } + + btf = btf__load_from_kernel_by_id(map_info.btf_id); + if (!btf) + goto out_close; + datasec = btf__type_by_id(btf, map_info.btf_value_type_id); + if (!btf_is_datasec(datasec)) + goto out_free_btf; + + /* + * If there aren't any variables with the "bpf_metadata_" prefix, + * don't bother. + */ + vlen = btf_vlen(datasec); + vsi = btf_var_secinfos(datasec); + vars = 0; + for (unsigned int i = 0; i < vlen; i++, vsi++) { + const struct btf_type *t_var = btf__type_by_id(btf, vsi->type); + const char *name = btf__name_by_offset(btf, t_var->name_off); + + if (name_has_bpf_metadata_prefix(&name)) + vars++; + } + if (vars == 0) + goto out_free_btf; + + rodata = zalloc(map_info.value_size); + if (!rodata) + goto out_free_btf; + key = 0; + if (bpf_map_lookup_elem(map_fd, &key, rodata)) { + free(rodata); + goto out_free_btf; + } + close(map_fd); + + map->btf = btf; + map->datasec = datasec; + map->rodata = rodata; + map->rodata_size = map_info.value_size; + map->num_vars = vars; + return 0; + +out_free_btf: + btf__free(btf); +out_close: + close(map_fd); + return -1; +} + +struct format_btf_ctx { + char *buf; + size_t buf_size; + size_t buf_idx; +}; + +static void format_btf_cb(void *arg, const char *fmt, va_list ap) +{ + int n; + struct format_btf_ctx *ctx = (struct format_btf_ctx *)arg; + + n = vsnprintf(ctx->buf + ctx->buf_idx, ctx->buf_size - ctx->buf_idx, + fmt, ap); + ctx->buf_idx += n; + if (ctx->buf_idx >= ctx->buf_size) + ctx->buf_idx = ctx->buf_size; +} + +static void format_btf_variable(struct btf *btf, char *buf, size_t buf_size, + const struct btf_type *t, const void *btf_data) +{ + struct format_btf_ctx ctx = { + .buf = buf, + .buf_idx = 0, + .buf_size = buf_size, + }; + const struct btf_dump_type_data_opts opts = { + .sz = sizeof(struct btf_dump_type_data_opts), + .skip_names = 1, + .compact = 1, + .emit_strings = 1, + }; + struct btf_dump *d; + size_t btf_size; + + d = btf_dump__new(btf, format_btf_cb, &ctx, NULL); + btf_size = btf__resolve_size(btf, t->type); + btf_dump__dump_type_data(d, t->type, btf_data, btf_size, &opts); + btf_dump__free(d); +} + +static void bpf_metadata_fill_event(struct bpf_metadata_map *map, + struct perf_record_bpf_metadata *bpf_metadata_event) +{ + struct btf_var_secinfo *vsi; + unsigned int i, vlen; + + memset(bpf_metadata_event->prog_name, 0, BPF_PROG_NAME_LEN); + vlen = btf_vlen(map->datasec); + vsi = btf_var_secinfos(map->datasec); + + for (i = 0; i < vlen; i++, vsi++) { + const struct btf_type *t_var = btf__type_by_id(map->btf, + vsi->type); + const char *name = btf__name_by_offset(map->btf, + t_var->name_off); + const __u64 nr_entries = bpf_metadata_event->nr_entries; + struct perf_record_bpf_metadata_entry *entry; + + if (!name_has_bpf_metadata_prefix(&name)) + continue; + + if (nr_entries >= (__u64)map->num_vars) + break; + + entry = &bpf_metadata_event->entries[nr_entries]; + memset(entry, 0, sizeof(*entry)); + snprintf(entry->key, BPF_METADATA_KEY_LEN, "%s", name); + format_btf_variable(map->btf, entry->value, + BPF_METADATA_VALUE_LEN, t_var, + map->rodata + vsi->offset); + bpf_metadata_event->nr_entries++; + } +} + +static void bpf_metadata_free_map_data(struct bpf_metadata_map *map) +{ + btf__free(map->btf); + free(map->rodata); +} + +static struct bpf_metadata *bpf_metadata_alloc(__u32 nr_prog_tags, + __u32 nr_variables) +{ + struct bpf_metadata *metadata; + size_t event_size; + + metadata = zalloc(sizeof(struct bpf_metadata)); + if (!metadata) + return NULL; + + metadata->prog_names = zalloc(nr_prog_tags * sizeof(char *)); + if (!metadata->prog_names) { + bpf_metadata_free(metadata); + return NULL; + } + for (__u32 prog_index = 0; prog_index < nr_prog_tags; prog_index++) { + metadata->prog_names[prog_index] = zalloc(BPF_PROG_NAME_LEN); + if (!metadata->prog_names[prog_index]) { + bpf_metadata_free(metadata); + return NULL; + } + metadata->nr_prog_names++; + } + + event_size = sizeof(metadata->event->bpf_metadata) + + nr_variables * sizeof(metadata->event->bpf_metadata.entries[0]); + metadata->event = zalloc(event_size); + if (!metadata->event) { + bpf_metadata_free(metadata); + return NULL; + } + metadata->event->bpf_metadata = (struct perf_record_bpf_metadata) { + .header = { + .type = PERF_RECORD_BPF_METADATA, + .size = event_size, + }, + .nr_entries = 0, + }; + + return metadata; +} + +static struct bpf_metadata *bpf_metadata_create(struct bpf_prog_info *info) +{ + struct bpf_metadata *metadata; + const __u32 *map_ids = (__u32 *)(uintptr_t)info->map_ids; + + for (__u32 map_index = 0; map_index < info->nr_map_ids; map_index++) { + struct bpf_metadata_map map; + + if (bpf_metadata_read_map_data(map_ids[map_index], &map) != 0) + continue; + + metadata = bpf_metadata_alloc(info->nr_prog_tags, map.num_vars); + if (!metadata) + continue; + + bpf_metadata_fill_event(&map, &metadata->event->bpf_metadata); + + for (__u32 index = 0; index < info->nr_prog_tags; index++) { + synthesize_bpf_prog_name(metadata->prog_names[index], + BPF_PROG_NAME_LEN, info, + map.btf, index); + } + + bpf_metadata_free_map_data(&map); + + return metadata; + } + + return NULL; +} + +static int synthesize_perf_record_bpf_metadata(const struct bpf_metadata *metadata, + const struct perf_tool *tool, + perf_event__handler_t process, + struct machine *machine) +{ + const size_t event_size = metadata->event->header.size; + union perf_event *event; + int err = 0; + + event = zalloc(event_size + machine->id_hdr_size); + if (!event) + return -1; + memcpy(event, metadata->event, event_size); + memset((void *)event + event->header.size, 0, machine->id_hdr_size); + event->header.size += machine->id_hdr_size; + for (__u32 index = 0; index < metadata->nr_prog_names; index++) { + memcpy(event->bpf_metadata.prog_name, + metadata->prog_names[index], BPF_PROG_NAME_LEN); + err = perf_tool__process_synth_event(tool, event, machine, + process); + if (err != 0) + break; + } + + free(event); + return err; +} + +void bpf_metadata_free(struct bpf_metadata *metadata) +{ + if (metadata == NULL) + return; + for (__u32 index = 0; index < metadata->nr_prog_names; index++) + free(metadata->prog_names[index]); + free(metadata->prog_names); + free(metadata->event); + free(metadata); +} + +#else /* HAVE_LIBBPF_STRINGS_SUPPORT */ + +static struct bpf_metadata *bpf_metadata_create(struct bpf_prog_info *info __maybe_unused) +{ + return NULL; +} + +static int synthesize_perf_record_bpf_metadata(const struct bpf_metadata *metadata __maybe_unused, + const struct perf_tool *tool __maybe_unused, + perf_event__handler_t process __maybe_unused, + struct machine *machine __maybe_unused) +{ + return 0; +} + +void bpf_metadata_free(struct bpf_metadata *metadata __maybe_unused) +{ +} + +#endif /* HAVE_LIBBPF_STRINGS_SUPPORT */ + +struct bpf_metadata_final_ctx { + const struct perf_tool *tool; + perf_event__handler_t process; + struct machine *machine; +}; + +static void synthesize_final_bpf_metadata_cb(struct bpf_prog_info_node *node, + void *data) +{ + struct bpf_metadata_final_ctx *ctx = (struct bpf_metadata_final_ctx *)data; + struct bpf_metadata *metadata = node->metadata; + int err; + + if (metadata == NULL) + return; + err = synthesize_perf_record_bpf_metadata(metadata, ctx->tool, + ctx->process, ctx->machine); + if (err != 0) { + const char *prog_name = metadata->prog_names[0]; + + if (prog_name != NULL) + pr_warning("Couldn't synthesize final BPF metadata for %s.\n", prog_name); + else + pr_warning("Couldn't synthesize final BPF metadata.\n"); + } + bpf_metadata_free(metadata); + node->metadata = NULL; +} + +void perf_event__synthesize_final_bpf_metadata(struct perf_session *session, + perf_event__handler_t process) +{ + struct perf_env *env = &session->header.env; + struct bpf_metadata_final_ctx ctx = { + .tool = session->tool, + .process = process, + .machine = &session->machines.host, + }; + + perf_env__iterate_bpf_prog_info(env, synthesize_final_bpf_metadata_cb, + &ctx); +} + /* * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf * program. One PERF_RECORD_BPF_EVENT is generated for the program. And @@ -164,9 +534,10 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, { 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; + const struct perf_tool *tool = session->tool; struct bpf_prog_info_node *info_node; + struct perf_bpil *info_linear; + struct bpf_metadata *metadata; struct bpf_prog_info *info; struct btf *btf = NULL; struct perf_env *env; @@ -178,17 +549,18 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, * 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); + env = perf_session__env(session); + + arrays = 1UL << PERF_BPIL_JITED_KSYMS; + arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS; + arrays |= 1UL << PERF_BPIL_FUNC_INFO; + arrays |= 1UL << PERF_BPIL_PROG_TAGS; + arrays |= 1UL << PERF_BPIL_JITED_INSNS; + arrays |= 1UL << PERF_BPIL_LINE_INFO; + arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO; + arrays |= 1UL << PERF_BPIL_MAP_IDS; + + info_linear = get_bpf_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__); @@ -196,30 +568,37 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, } if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) { + free(info_linear); pr_debug("%s: the kernel is too old, aborting\n", __func__); return -2; } info = &info_linear->info; + if (!info->jited_ksyms) { + free(info_linear); + return -1; + } /* 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) + sub_prog_cnt != info->nr_jited_func_lens) { + free(info_linear); 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; + free(info_linear); + return -1; } - if (btf__get_from_id(info->btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(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); @@ -276,7 +655,11 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, } info_node->info_linear = info_linear; - perf_env__insert_bpf_prog_info(env, info_node); + info_node->metadata = NULL; + if (!perf_env__insert_bpf_prog_info(env, info_node)) { + free(info_linear); + free(info_node); + } info_linear = NULL; /* @@ -285,11 +668,20 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, */ err = perf_tool__process_synth_event(tool, event, machine, process); + + /* Synthesize PERF_RECORD_BPF_METADATA */ + metadata = bpf_metadata_create(info); + if (metadata != NULL) { + err = synthesize_perf_record_bpf_metadata(metadata, + tool, process, + machine); + bpf_metadata_free(metadata); + } } out: free(info_linear); - free(btf); + btf__free(btf); return err ? -1 : 0; } @@ -297,7 +689,7 @@ struct kallsyms_parse { union perf_event *event; perf_event__handler_t process; struct machine *machine; - struct perf_tool *tool; + const struct perf_tool *tool; }; static int @@ -374,6 +766,9 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, int err; int fd; + if (opts->no_bpf_event) + return 0; + event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size); if (!event) return -1; @@ -434,8 +829,8 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, 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 perf_bpil *info_linear; struct btf *btf = NULL; u64 arrays; u32 btf_id; @@ -445,15 +840,16 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 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; + arrays = 1UL << PERF_BPIL_JITED_KSYMS; + arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS; + arrays |= 1UL << PERF_BPIL_FUNC_INFO; + arrays |= 1UL << PERF_BPIL_PROG_TAGS; + arrays |= 1UL << PERF_BPIL_JITED_INSNS; + arrays |= 1UL << PERF_BPIL_LINE_INFO; + arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO; + arrays |= 1UL << PERF_BPIL_MAP_IDS; - info_linear = bpf_program__get_prog_info_linear(fd, arrays); + info_linear = get_bpf_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; @@ -464,14 +860,19 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 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); + info_node->metadata = bpf_metadata_create(&info_linear->info); + if (!perf_env__insert_bpf_prog_info(env, info_node)) { + free(info_linear); + free(info_node); + } } else free(info_linear); if (btf_id == 0) goto out; - if (btf__get_from_id(btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(btf_id); + if (libbpf_get_error(btf)) { pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, btf_id); goto out; @@ -479,7 +880,7 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id) perf_env__fetch_btf(env, btf_id, btf); out: - free(btf); + btf__free(btf); close(fd); } @@ -526,12 +927,12 @@ int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env) */ attr.wakeup_watermark = 1; - return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env); + return 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) +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); @@ -547,7 +948,7 @@ void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, if (info->btf_id) { struct btf_node *node; - node = perf_env__find_btf(env, info->btf_id); + node = __perf_env__find_btf(env, info->btf_id); if (node) btf = btf__new((__u8 *)(node->data), node->data_size); @@ -557,7 +958,7 @@ void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, 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]); - return; + goto out; } fprintf(fp, "# bpf_prog_info %u:\n", info->id); @@ -567,4 +968,6 @@ void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n", i, name, prog_addrs[i], prog_lens[i]); } +out: + btf__free(btf); } |