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

source code of linux/tools/perf/bench/evlist-open-close.c