1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * |
4 | * sched-pipe.c |
5 | * |
6 | * pipe: Benchmark for pipe() |
7 | * |
8 | * Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com> |
9 | * http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c |
10 | * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> |
11 | */ |
12 | #include <subcmd/parse-options.h> |
13 | #include <api/fs/fs.h> |
14 | #include "bench.h" |
15 | #include "util/cgroup.h" |
16 | |
17 | #include <unistd.h> |
18 | #include <stdio.h> |
19 | #include <stdlib.h> |
20 | #include <signal.h> |
21 | #include <sys/wait.h> |
22 | #include <string.h> |
23 | #include <errno.h> |
24 | #include <fcntl.h> |
25 | #include <assert.h> |
26 | #include <sys/time.h> |
27 | #include <sys/types.h> |
28 | #include <sys/syscall.h> |
29 | #include <linux/time64.h> |
30 | |
31 | #include <pthread.h> |
32 | |
33 | struct thread_data { |
34 | int nr; |
35 | int pipe_read; |
36 | int pipe_write; |
37 | bool cgroup_failed; |
38 | pthread_t pthread; |
39 | }; |
40 | |
41 | #define LOOPS_DEFAULT 1000000 |
42 | static int loops = LOOPS_DEFAULT; |
43 | |
44 | /* Use processes by default: */ |
45 | static bool threaded; |
46 | |
47 | static char *cgrp_names[2]; |
48 | static struct cgroup *cgrps[2]; |
49 | |
50 | static int parse_two_cgroups(const struct option *opt __maybe_unused, |
51 | const char *str, int unset __maybe_unused) |
52 | { |
53 | char *p = strdup(str); |
54 | char *q; |
55 | int ret = -1; |
56 | |
57 | if (p == NULL) { |
58 | fprintf(stderr, "memory allocation failure\n" ); |
59 | return -1; |
60 | } |
61 | |
62 | q = strchr(p, ','); |
63 | if (q == NULL) { |
64 | fprintf(stderr, "it should have two cgroup names: %s\n" , p); |
65 | goto out; |
66 | } |
67 | *q = '\0'; |
68 | |
69 | cgrp_names[0] = strdup(p); |
70 | cgrp_names[1] = strdup(q + 1); |
71 | |
72 | if (cgrp_names[0] == NULL || cgrp_names[1] == NULL) { |
73 | fprintf(stderr, "memory allocation failure\n" ); |
74 | goto out; |
75 | } |
76 | ret = 0; |
77 | |
78 | out: |
79 | free(p); |
80 | return ret; |
81 | } |
82 | |
83 | static const struct option options[] = { |
84 | OPT_INTEGER('l', "loop" , &loops, "Specify number of loops" ), |
85 | OPT_BOOLEAN('T', "threaded" , &threaded, "Specify threads/process based task setup" ), |
86 | OPT_CALLBACK('G', "cgroups" , NULL, "SEND,RECV" , |
87 | "Put sender and receivers in given cgroups" , |
88 | parse_two_cgroups), |
89 | OPT_END() |
90 | }; |
91 | |
92 | static const char * const bench_sched_pipe_usage[] = { |
93 | "perf bench sched pipe <options>" , |
94 | NULL |
95 | }; |
96 | |
97 | static int enter_cgroup(int nr) |
98 | { |
99 | char buf[32]; |
100 | int fd, len, ret; |
101 | int saved_errno; |
102 | struct cgroup *cgrp; |
103 | pid_t pid; |
104 | |
105 | if (cgrp_names[nr] == NULL) |
106 | return 0; |
107 | |
108 | if (cgrps[nr] == NULL) { |
109 | cgrps[nr] = cgroup__new(cgrp_names[nr], /*do_open=*/true); |
110 | if (cgrps[nr] == NULL) |
111 | goto err; |
112 | } |
113 | cgrp = cgrps[nr]; |
114 | |
115 | if (threaded) |
116 | pid = syscall(__NR_gettid); |
117 | else |
118 | pid = getpid(); |
119 | |
120 | snprintf(buf, sizeof(buf), "%d\n" , pid); |
121 | len = strlen(buf); |
122 | |
123 | /* try cgroup v2 interface first */ |
124 | if (threaded) |
125 | fd = openat(cgrp->fd, "cgroup.threads" , O_WRONLY); |
126 | else |
127 | fd = openat(cgrp->fd, "cgroup.procs" , O_WRONLY); |
128 | |
129 | /* try cgroup v1 if failed */ |
130 | if (fd < 0 && errno == ENOENT) |
131 | fd = openat(cgrp->fd, "tasks" , O_WRONLY); |
132 | |
133 | if (fd < 0) |
134 | goto err; |
135 | |
136 | ret = write(fd, buf, len); |
137 | close(fd); |
138 | |
139 | if (ret != len) { |
140 | printf("Cannot enter to cgroup: %s\n" , cgrp->name); |
141 | return -1; |
142 | } |
143 | return 0; |
144 | |
145 | err: |
146 | saved_errno = errno; |
147 | printf("Failed to open cgroup file in %s\n" , cgrp_names[nr]); |
148 | |
149 | if (saved_errno == ENOENT) { |
150 | char mnt[PATH_MAX]; |
151 | |
152 | if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event" ) == 0) |
153 | printf(" Hint: create the cgroup first, like 'mkdir %s/%s'\n" , |
154 | mnt, cgrp_names[nr]); |
155 | } else if (saved_errno == EACCES && geteuid() > 0) { |
156 | printf(" Hint: try to run as root\n" ); |
157 | } |
158 | |
159 | return -1; |
160 | } |
161 | |
162 | static void exit_cgroup(int nr) |
163 | { |
164 | cgroup__put(cgrps[nr]); |
165 | free(cgrp_names[nr]); |
166 | } |
167 | |
168 | static void *worker_thread(void *__tdata) |
169 | { |
170 | struct thread_data *td = __tdata; |
171 | int m = 0, i; |
172 | int ret; |
173 | |
174 | ret = enter_cgroup(nr: td->nr); |
175 | if (ret < 0) { |
176 | td->cgroup_failed = true; |
177 | return NULL; |
178 | } |
179 | |
180 | for (i = 0; i < loops; i++) { |
181 | if (!td->nr) { |
182 | ret = read(td->pipe_read, &m, sizeof(int)); |
183 | BUG_ON(ret != sizeof(int)); |
184 | ret = write(td->pipe_write, &m, sizeof(int)); |
185 | BUG_ON(ret != sizeof(int)); |
186 | } else { |
187 | ret = write(td->pipe_write, &m, sizeof(int)); |
188 | BUG_ON(ret != sizeof(int)); |
189 | ret = read(td->pipe_read, &m, sizeof(int)); |
190 | BUG_ON(ret != sizeof(int)); |
191 | } |
192 | } |
193 | |
194 | return NULL; |
195 | } |
196 | |
197 | int bench_sched_pipe(int argc, const char **argv) |
198 | { |
199 | struct thread_data threads[2] = {}; |
200 | struct thread_data *td; |
201 | int pipe_1[2], pipe_2[2]; |
202 | struct timeval start, stop, diff; |
203 | unsigned long long result_usec = 0; |
204 | int nr_threads = 2; |
205 | int t; |
206 | |
207 | /* |
208 | * why does "ret" exist? |
209 | * discarding returned value of read(), write() |
210 | * causes error in building environment for perf |
211 | */ |
212 | int __maybe_unused ret, wait_stat; |
213 | pid_t pid, retpid __maybe_unused; |
214 | |
215 | argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0); |
216 | |
217 | BUG_ON(pipe(pipe_1)); |
218 | BUG_ON(pipe(pipe_2)); |
219 | |
220 | gettimeofday(&start, NULL); |
221 | |
222 | for (t = 0; t < nr_threads; t++) { |
223 | td = threads + t; |
224 | |
225 | td->nr = t; |
226 | |
227 | if (t == 0) { |
228 | td->pipe_read = pipe_1[0]; |
229 | td->pipe_write = pipe_2[1]; |
230 | } else { |
231 | td->pipe_write = pipe_1[1]; |
232 | td->pipe_read = pipe_2[0]; |
233 | } |
234 | } |
235 | |
236 | if (threaded) { |
237 | for (t = 0; t < nr_threads; t++) { |
238 | td = threads + t; |
239 | |
240 | ret = pthread_create(&td->pthread, NULL, worker_thread, td); |
241 | BUG_ON(ret); |
242 | } |
243 | |
244 | for (t = 0; t < nr_threads; t++) { |
245 | td = threads + t; |
246 | |
247 | ret = pthread_join(td->pthread, NULL); |
248 | BUG_ON(ret); |
249 | } |
250 | } else { |
251 | pid = fork(); |
252 | assert(pid >= 0); |
253 | |
254 | if (!pid) { |
255 | worker_thread(tdata: threads + 0); |
256 | exit(0); |
257 | } else { |
258 | worker_thread(tdata: threads + 1); |
259 | } |
260 | |
261 | retpid = waitpid(pid, &wait_stat, 0); |
262 | assert((retpid == pid) && WIFEXITED(wait_stat)); |
263 | } |
264 | |
265 | gettimeofday(&stop, NULL); |
266 | timersub(&stop, &start, &diff); |
267 | |
268 | exit_cgroup(nr: 0); |
269 | exit_cgroup(nr: 1); |
270 | |
271 | if (threads[0].cgroup_failed || threads[1].cgroup_failed) |
272 | return 0; |
273 | |
274 | switch (bench_format) { |
275 | case BENCH_FORMAT_DEFAULT: |
276 | printf("# Executed %d pipe operations between two %s\n\n" , |
277 | loops, threaded ? "threads" : "processes" ); |
278 | |
279 | result_usec = diff.tv_sec * USEC_PER_SEC; |
280 | result_usec += diff.tv_usec; |
281 | |
282 | printf(" %14s: %lu.%03lu [sec]\n\n" , "Total time" , |
283 | (unsigned long) diff.tv_sec, |
284 | (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); |
285 | |
286 | printf(" %14lf usecs/op\n" , |
287 | (double)result_usec / (double)loops); |
288 | printf(" %14d ops/sec\n" , |
289 | (int)((double)loops / |
290 | ((double)result_usec / (double)USEC_PER_SEC))); |
291 | break; |
292 | |
293 | case BENCH_FORMAT_SIMPLE: |
294 | printf("%lu.%03lu\n" , |
295 | (unsigned long) diff.tv_sec, |
296 | (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); |
297 | break; |
298 | |
299 | default: |
300 | /* reaching here is something disaster */ |
301 | fprintf(stderr, "Unknown format:%d\n" , bench_format); |
302 | exit(1); |
303 | break; |
304 | } |
305 | |
306 | return 0; |
307 | } |
308 | |