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.
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	16
29
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_ret
58print_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