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/or
4 * modify it under the terms of version 2 of the GNU General Public
5 * License as published by the Free Software Foundation.
9 #include <bpf/libbpf.h>
18 #include <linux/bpf.h>
19 #include <linux/perf_event.h>
20 #include <sys/ioctl.h>
22 #include <sys/syscall.h>
29 #define MMAP_PAGE_CNT 16
31 static volatile bool stop;
33 struct event_ring_info {
40 struct perf_event_sample {
41 struct perf_event_header header;
47 struct perf_event_lost {
48 struct perf_event_header header;
53 static void int_exit(int signo)
55 fprintf(stderr, "Stopping...\n");
59 struct event_pipe_ctx {
65 static enum bpf_perf_event_ret
66 print_bpf_output(void *private_data, int cpu, struct perf_event_header *event)
68 struct perf_event_sample *e = container_of(event,
69 struct perf_event_sample,
71 struct perf_event_lost *lost = container_of(event,
72 struct perf_event_lost,
74 struct event_pipe_ctx *ctx = private_data;
75 int idx = ctx->all_cpus ? cpu : ctx->idx;
78 jsonw_start_object(json_wtr);
79 jsonw_name(json_wtr, "type");
80 jsonw_uint(json_wtr, e->header.type);
81 jsonw_name(json_wtr, "cpu");
82 jsonw_uint(json_wtr, cpu);
83 jsonw_name(json_wtr, "index");
84 jsonw_uint(json_wtr, idx);
85 if (e->header.type == PERF_RECORD_SAMPLE) {
86 jsonw_name(json_wtr, "timestamp");
87 jsonw_uint(json_wtr, e->time);
88 jsonw_name(json_wtr, "data");
89 print_data_json(e->data, e->size);
90 } else if (e->header.type == PERF_RECORD_LOST) {
91 jsonw_name(json_wtr, "lost");
92 jsonw_start_object(json_wtr);
93 jsonw_name(json_wtr, "id");
94 jsonw_uint(json_wtr, lost->id);
95 jsonw_name(json_wtr, "count");
96 jsonw_uint(json_wtr, lost->lost);
97 jsonw_end_object(json_wtr);
99 jsonw_end_object(json_wtr);
101 if (e->header.type == PERF_RECORD_SAMPLE) {
102 printf("== @%lld.%09lld CPU: %d index: %d =====\n",
103 e->time / 1000000000ULL, e->time % 1000000000ULL,
105 fprint_hex(stdout, e->data, e->size, " ");
107 } else if (e->header.type == PERF_RECORD_LOST) {
108 printf("lost %lld events\n", lost->lost);
110 printf("unknown event type=%d size=%d\n",
111 e->header.type, e->header.size);
115 return LIBBPF_PERF_EVENT_CONT;
118 int do_event_pipe(int argc, char **argv)
120 struct perf_event_attr perf_attr = {
121 .sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_TIME,
122 .type = PERF_TYPE_SOFTWARE,
123 .config = PERF_COUNT_SW_BPF_OUTPUT,
127 struct bpf_map_info map_info = {};
128 struct perf_buffer_raw_opts opts = {};
129 struct event_pipe_ctx ctx = {
134 struct perf_buffer *pb;
138 map_info_len = sizeof(map_info);
139 map_fd = map_parse_fd_and_info(&argc, &argv, &map_info, &map_info_len);
143 if (map_info.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
144 p_err("map is not a perf event array");
154 if (is_prefix(*argv, "cpu")) {
158 ctx.cpu = strtoul(*argv, &endptr, 0);
160 p_err("can't parse %s as CPU ID", *argv);
165 } else if (is_prefix(*argv, "index")) {
169 ctx.idx = strtoul(*argv, &endptr, 0);
171 p_err("can't parse %s as index", *argv);
181 ctx.all_cpus = false;
185 if (ctx.idx == -1 || ctx.cpu == -1) {
186 p_err("cpu and index must be specified together");
194 opts.attr = &perf_attr;
195 opts.event_cb = print_bpf_output;
197 opts.cpu_cnt = ctx.all_cpus ? 0 : 1;
198 opts.cpus = &ctx.cpu;
199 opts.map_keys = &ctx.idx;
201 pb = perf_buffer__new_raw(map_fd, MMAP_PAGE_CNT, &opts);
202 err = libbpf_get_error(pb);
204 p_err("failed to create perf buffer: %s (%d)",
209 signal(SIGINT, int_exit);
210 signal(SIGHUP, int_exit);
211 signal(SIGTERM, int_exit);
214 jsonw_start_array(json_wtr);
217 err = perf_buffer__poll(pb, 200);
218 if (err < 0 && err != -EINTR) {
219 p_err("perf buffer polling failed: %s (%d)",
226 jsonw_end_array(json_wtr);
228 perf_buffer__free(pb);
234 perf_buffer__free(pb);