xref: /linux/tools/perf/bench/evlist-open-close.c (revision e78f70bad29c5ae1e1076698b690b15794e9b81e)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <inttypes.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <limits.h>
6 #include "bench.h"
7 #include "../util/debug.h"
8 #include "../util/stat.h"
9 #include "../util/evlist.h"
10 #include "../util/evsel.h"
11 #include "../util/strbuf.h"
12 #include "../util/record.h"
13 #include "../util/parse-events.h"
14 #include "internal/threadmap.h"
15 #include "internal/cpumap.h"
16 #include <linux/perf_event.h>
17 #include <linux/kernel.h>
18 #include <linux/time64.h>
19 #include <linux/string.h>
20 #include <subcmd/parse-options.h>
21 
22 #define MMAP_FLUSH_DEFAULT 1
23 
24 static int iterations = 100;
25 static int nr_events = 1;
26 static const char *event_string = "dummy";
27 
28 static inline u64 timeval2usec(struct timeval *tv)
29 {
30 	return tv->tv_sec * USEC_PER_SEC + tv->tv_usec;
31 }
32 
33 static struct record_opts opts = {
34 	.sample_time	     = true,
35 	.mmap_pages	     = UINT_MAX,
36 	.user_freq	     = UINT_MAX,
37 	.user_interval	     = ULLONG_MAX,
38 	.freq		     = 4000,
39 	.target		     = {
40 		.uses_mmap   = true,
41 		.default_per_cpu = true,
42 	},
43 	.mmap_flush          = MMAP_FLUSH_DEFAULT,
44 	.nr_threads_synthesize = 1,
45 	.ctl_fd              = -1,
46 	.ctl_fd_ack          = -1,
47 };
48 
49 static int evlist__count_evsel_fds(struct evlist *evlist)
50 {
51 	struct evsel *evsel;
52 	int cnt = 0;
53 
54 	evlist__for_each_entry(evlist, evsel)
55 		cnt += evsel->core.threads->nr * perf_cpu_map__nr(evsel->core.cpus);
56 
57 	return cnt;
58 }
59 
60 static struct evlist *bench__create_evlist(char *evstr)
61 {
62 	struct parse_events_error err;
63 	struct evlist *evlist = evlist__new();
64 	int ret;
65 
66 	if (!evlist) {
67 		pr_err("Not enough memory to create evlist\n");
68 		return NULL;
69 	}
70 
71 	parse_events_error__init(&err);
72 	ret = parse_events(evlist, evstr, &err);
73 	if (ret) {
74 		parse_events_error__print(&err, evstr);
75 		parse_events_error__exit(&err);
76 		pr_err("Run 'perf list' for a list of valid events\n");
77 		ret = 1;
78 		goto out_delete_evlist;
79 	}
80 	parse_events_error__exit(&err);
81 	ret = evlist__create_maps(evlist, &opts.target);
82 	if (ret < 0) {
83 		pr_err("Not enough memory to create thread/cpu maps\n");
84 		goto out_delete_evlist;
85 	}
86 
87 	evlist__config(evlist, &opts, NULL);
88 
89 	return evlist;
90 
91 out_delete_evlist:
92 	evlist__delete(evlist);
93 	return NULL;
94 }
95 
96 static int bench__do_evlist_open_close(struct evlist *evlist)
97 {
98 	char sbuf[STRERR_BUFSIZE];
99 	int err = evlist__open(evlist);
100 
101 	if (err < 0) {
102 		pr_err("evlist__open: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
103 		return err;
104 	}
105 
106 	err = evlist__mmap(evlist, opts.mmap_pages);
107 	if (err < 0) {
108 		pr_err("evlist__mmap: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
109 		return err;
110 	}
111 
112 	evlist__enable(evlist);
113 	evlist__disable(evlist);
114 	evlist__munmap(evlist);
115 	evlist__close(evlist);
116 
117 	return 0;
118 }
119 
120 static int bench_evlist_open_close__run(char *evstr)
121 {
122 	// used to print statistics only
123 	struct evlist *evlist = bench__create_evlist(evstr);
124 	double time_average, time_stddev;
125 	struct timeval start, end, diff;
126 	struct stats time_stats;
127 	u64 runtime_us;
128 	int i, err;
129 
130 	if (!evlist)
131 		return -ENOMEM;
132 
133 	init_stats(&time_stats);
134 
135 	printf("  Number of cpus:\t%d\n", perf_cpu_map__nr(evlist->core.user_requested_cpus));
136 	printf("  Number of threads:\t%d\n", evlist->core.threads->nr);
137 	printf("  Number of events:\t%d (%d fds)\n",
138 		evlist->core.nr_entries, evlist__count_evsel_fds(evlist));
139 	printf("  Number of iterations:\t%d\n", iterations);
140 
141 	evlist__delete(evlist);
142 
143 	for (i = 0; i < iterations; i++) {
144 		pr_debug("Started iteration %d\n", i);
145 		evlist = bench__create_evlist(evstr);
146 		if (!evlist)
147 			return -ENOMEM;
148 
149 		gettimeofday(&start, NULL);
150 		err = bench__do_evlist_open_close(evlist);
151 		if (err) {
152 			evlist__delete(evlist);
153 			return err;
154 		}
155 
156 		gettimeofday(&end, NULL);
157 		timersub(&end, &start, &diff);
158 		runtime_us = timeval2usec(&diff);
159 		update_stats(&time_stats, runtime_us);
160 
161 		evlist__delete(evlist);
162 		pr_debug("Iteration %d took:\t%" PRIu64 "us\n", i, runtime_us);
163 	}
164 
165 	time_average = avg_stats(&time_stats);
166 	time_stddev = stddev_stats(&time_stats);
167 	printf("  Average open-close took: %.3f usec (+- %.3f usec)\n", time_average, time_stddev);
168 
169 	return 0;
170 }
171 
172 static char *bench__repeat_event_string(const char *evstr, int n)
173 {
174 	char sbuf[STRERR_BUFSIZE];
175 	struct strbuf buf;
176 	int i, str_size = strlen(evstr),
177 	    final_size = str_size * n + n,
178 	    err = strbuf_init(&buf, final_size);
179 
180 	if (err) {
181 		pr_err("strbuf_init: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
182 		goto out_error;
183 	}
184 
185 	for (i = 0; i < n; i++) {
186 		err = strbuf_add(&buf, evstr, str_size);
187 		if (err) {
188 			pr_err("strbuf_add: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
189 			goto out_error;
190 		}
191 
192 		err = strbuf_addch(&buf, i == n-1 ? '\0' : ',');
193 		if (err) {
194 			pr_err("strbuf_addch: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
195 			goto out_error;
196 		}
197 	}
198 
199 	return strbuf_detach(&buf, NULL);
200 
201 out_error:
202 	strbuf_release(&buf);
203 	return NULL;
204 }
205 
206 
207 int bench_evlist_open_close(int argc, const char **argv)
208 {
209 	const struct option options[] = {
210 		OPT_STRING('e', "event", &event_string, "event",
211 			   "event selector. use 'perf list' to list available events"),
212 		OPT_INTEGER('n', "nr-events", &nr_events,
213 			    "number of dummy events to create (default 1). If used with -e, it clones those events n times (1 = no change)"),
214 		OPT_INTEGER('i', "iterations", &iterations,
215 			    "Number of iterations used to compute average (default=100)"),
216 		OPT_BOOLEAN('a', "all-cpus", &opts.target.system_wide,
217 			    "system-wide collection from all CPUs"),
218 		OPT_STRING('C', "cpu", &opts.target.cpu_list, "cpu",
219 			   "list of cpus where to open events"),
220 		OPT_STRING('p', "pid", &opts.target.pid, "pid",
221 			   "record events on existing process id"),
222 		OPT_STRING('t', "tid", &opts.target.tid, "tid",
223 			   "record events on existing thread id"),
224 		OPT_STRING('u', "uid", &opts.target.uid_str, "user", "user to profile"),
225 		OPT_BOOLEAN(0, "per-thread", &opts.target.per_thread, "use per-thread mmaps"),
226 		OPT_END()
227 	};
228 	const char *const bench_usage[] = {
229 		"perf bench internals evlist-open-close <options>",
230 		NULL
231 	};
232 	char *evstr, errbuf[BUFSIZ];
233 	int err;
234 
235 	argc = parse_options(argc, argv, options, bench_usage, 0);
236 	if (argc) {
237 		usage_with_options(bench_usage, options);
238 		exit(EXIT_FAILURE);
239 	}
240 
241 	err = target__validate(&opts.target);
242 	if (err) {
243 		target__strerror(&opts.target, err, errbuf, sizeof(errbuf));
244 		pr_err("%s\n", errbuf);
245 		goto out;
246 	}
247 
248 	err = target__parse_uid(&opts.target);
249 	if (err) {
250 		target__strerror(&opts.target, err, errbuf, sizeof(errbuf));
251 		pr_err("%s", errbuf);
252 		goto out;
253 	}
254 
255 	/* Enable ignoring missing threads when -u/-p option is defined. */
256 	opts.ignore_missing_thread = opts.target.uid != UINT_MAX || opts.target.pid;
257 
258 	evstr = bench__repeat_event_string(event_string, nr_events);
259 	if (!evstr) {
260 		err = -ENOMEM;
261 		goto out;
262 	}
263 
264 	err = bench_evlist_open_close__run(evstr);
265 
266 	free(evstr);
267 out:
268 	return err;
269 }
270