227 lines · c
1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)2/* Copyright (C) 2018 Netronome Systems, Inc. */3/* This program is free software; you can redistribute it and/or4 * modify it under the terms of version 2 of the GNU General Public5 * License as published by the Free Software Foundation.6 */7#include <errno.h>8#include <fcntl.h>9#include <bpf/libbpf.h>10#include <poll.h>11#include <signal.h>12#include <stdbool.h>13#include <stdio.h>14#include <stdlib.h>15#include <string.h>16#include <time.h>17#include <unistd.h>18#include <linux/bpf.h>19#include <linux/perf_event.h>20#include <sys/ioctl.h>21#include <sys/mman.h>22#include <sys/syscall.h>23 24#include <bpf/bpf.h>25 26#include "main.h"27 28#define MMAP_PAGE_CNT 1629 30static volatile bool stop;31 32struct perf_event_sample {33 struct perf_event_header header;34 __u64 time;35 __u32 size;36 unsigned char data[];37};38 39struct perf_event_lost {40 struct perf_event_header header;41 __u64 id;42 __u64 lost;43};44 45static void int_exit(int signo)46{47 fprintf(stderr, "Stopping...\n");48 stop = true;49}50 51struct event_pipe_ctx {52 bool all_cpus;53 int cpu;54 int idx;55};56 57static enum bpf_perf_event_ret58print_bpf_output(void *private_data, int cpu, struct perf_event_header *event)59{60 struct perf_event_sample *e = container_of(event,61 struct perf_event_sample,62 header);63 struct perf_event_lost *lost = container_of(event,64 struct perf_event_lost,65 header);66 struct event_pipe_ctx *ctx = private_data;67 int idx = ctx->all_cpus ? cpu : ctx->idx;68 69 if (json_output) {70 jsonw_start_object(json_wtr);71 jsonw_name(json_wtr, "type");72 jsonw_uint(json_wtr, e->header.type);73 jsonw_name(json_wtr, "cpu");74 jsonw_uint(json_wtr, cpu);75 jsonw_name(json_wtr, "index");76 jsonw_uint(json_wtr, idx);77 if (e->header.type == PERF_RECORD_SAMPLE) {78 jsonw_name(json_wtr, "timestamp");79 jsonw_uint(json_wtr, e->time);80 jsonw_name(json_wtr, "data");81 print_data_json(e->data, e->size);82 } else if (e->header.type == PERF_RECORD_LOST) {83 jsonw_name(json_wtr, "lost");84 jsonw_start_object(json_wtr);85 jsonw_name(json_wtr, "id");86 jsonw_uint(json_wtr, lost->id);87 jsonw_name(json_wtr, "count");88 jsonw_uint(json_wtr, lost->lost);89 jsonw_end_object(json_wtr);90 }91 jsonw_end_object(json_wtr);92 } else {93 if (e->header.type == PERF_RECORD_SAMPLE) {94 printf("== @%lld.%09lld CPU: %d index: %d =====\n",95 e->time / 1000000000ULL, e->time % 1000000000ULL,96 cpu, idx);97 fprint_hex(stdout, e->data, e->size, " ");98 printf("\n");99 } else if (e->header.type == PERF_RECORD_LOST) {100 printf("lost %lld events\n", lost->lost);101 } else {102 printf("unknown event type=%d size=%d\n",103 e->header.type, e->header.size);104 }105 }106 107 return LIBBPF_PERF_EVENT_CONT;108}109 110int do_event_pipe(int argc, char **argv)111{112 struct perf_event_attr perf_attr = {113 .sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_TIME,114 .type = PERF_TYPE_SOFTWARE,115 .config = PERF_COUNT_SW_BPF_OUTPUT,116 .sample_period = 1,117 .wakeup_events = 1,118 };119 struct bpf_map_info map_info = {};120 LIBBPF_OPTS(perf_buffer_raw_opts, opts);121 struct event_pipe_ctx ctx = {122 .all_cpus = true,123 .cpu = -1,124 .idx = -1,125 };126 struct perf_buffer *pb;127 __u32 map_info_len;128 int err, map_fd;129 130 map_info_len = sizeof(map_info);131 map_fd = map_parse_fd_and_info(&argc, &argv, &map_info, &map_info_len);132 if (map_fd < 0)133 return -1;134 135 if (map_info.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {136 p_err("map is not a perf event array");137 goto err_close_map;138 }139 140 while (argc) {141 if (argc < 2) {142 BAD_ARG();143 goto err_close_map;144 }145 146 if (is_prefix(*argv, "cpu")) {147 char *endptr;148 149 NEXT_ARG();150 ctx.cpu = strtoul(*argv, &endptr, 0);151 if (*endptr) {152 p_err("can't parse %s as CPU ID", *argv);153 goto err_close_map;154 }155 156 NEXT_ARG();157 } else if (is_prefix(*argv, "index")) {158 char *endptr;159 160 NEXT_ARG();161 ctx.idx = strtoul(*argv, &endptr, 0);162 if (*endptr) {163 p_err("can't parse %s as index", *argv);164 goto err_close_map;165 }166 167 NEXT_ARG();168 } else {169 BAD_ARG();170 goto err_close_map;171 }172 173 ctx.all_cpus = false;174 }175 176 if (!ctx.all_cpus) {177 if (ctx.idx == -1 || ctx.cpu == -1) {178 p_err("cpu and index must be specified together");179 goto err_close_map;180 }181 } else {182 ctx.cpu = 0;183 ctx.idx = 0;184 }185 186 opts.cpu_cnt = ctx.all_cpus ? 0 : 1;187 opts.cpus = &ctx.cpu;188 opts.map_keys = &ctx.idx;189 pb = perf_buffer__new_raw(map_fd, MMAP_PAGE_CNT, &perf_attr,190 print_bpf_output, &ctx, &opts);191 if (!pb) {192 p_err("failed to create perf buffer: %s (%d)",193 strerror(errno), errno);194 goto err_close_map;195 }196 197 signal(SIGINT, int_exit);198 signal(SIGHUP, int_exit);199 signal(SIGTERM, int_exit);200 201 if (json_output)202 jsonw_start_array(json_wtr);203 204 while (!stop) {205 err = perf_buffer__poll(pb, 200);206 if (err < 0 && err != -EINTR) {207 p_err("perf buffer polling failed: %s (%d)",208 strerror(errno), errno);209 goto err_close_pb;210 }211 }212 213 if (json_output)214 jsonw_end_array(json_wtr);215 216 perf_buffer__free(pb);217 close(map_fd);218 219 return 0;220 221err_close_pb:222 perf_buffer__free(pb);223err_close_map:224 close(map_fd);225 return -1;226}227