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11#include "../perf.h"
12#include "../util/util.h"
13#include "../util/parse-options.h"
14#include "../builtin.h"
15#include "bench.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 <assert.h>
25#include <sys/time.h>
26#include <sys/types.h>
27#include <sys/syscall.h>
28
29#include <pthread.h>
30
31struct thread_data {
32 int nr;
33 int pipe_read;
34 int pipe_write;
35 pthread_t pthread;
36};
37
38#define LOOPS_DEFAULT 1000000
39static int loops = LOOPS_DEFAULT;
40
41
42static bool threaded;
43
44static const struct option options[] = {
45 OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
46 OPT_BOOLEAN('T', "threaded", &threaded, "Specify threads/process based task setup"),
47 OPT_END()
48};
49
50static const char * const bench_sched_pipe_usage[] = {
51 "perf bench sched pipe <options>",
52 NULL
53};
54
55static void *worker_thread(void *__tdata)
56{
57 struct thread_data *td = __tdata;
58 int m = 0, i;
59 int ret;
60
61 for (i = 0; i < loops; i++) {
62 if (!td->nr) {
63 ret = read(td->pipe_read, &m, sizeof(int));
64 BUG_ON(ret != sizeof(int));
65 ret = write(td->pipe_write, &m, sizeof(int));
66 BUG_ON(ret != sizeof(int));
67 } else {
68 ret = write(td->pipe_write, &m, sizeof(int));
69 BUG_ON(ret != sizeof(int));
70 ret = read(td->pipe_read, &m, sizeof(int));
71 BUG_ON(ret != sizeof(int));
72 }
73 }
74
75 return NULL;
76}
77
78int bench_sched_pipe(int argc, const char **argv, const char *prefix __maybe_unused)
79{
80 struct thread_data threads[2], *td;
81 int pipe_1[2], pipe_2[2];
82 struct timeval start, stop, diff;
83 unsigned long long result_usec = 0;
84 int nr_threads = 2;
85 int t;
86
87
88
89
90
91
92 int __maybe_unused ret, wait_stat;
93 pid_t pid, retpid __maybe_unused;
94
95 argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0);
96
97 BUG_ON(pipe(pipe_1));
98 BUG_ON(pipe(pipe_2));
99
100 gettimeofday(&start, NULL);
101
102 for (t = 0; t < nr_threads; t++) {
103 td = threads + t;
104
105 td->nr = t;
106
107 if (t == 0) {
108 td->pipe_read = pipe_1[0];
109 td->pipe_write = pipe_2[1];
110 } else {
111 td->pipe_write = pipe_1[1];
112 td->pipe_read = pipe_2[0];
113 }
114 }
115
116
117 if (threaded) {
118
119 for (t = 0; t < nr_threads; t++) {
120 td = threads + t;
121
122 ret = pthread_create(&td->pthread, NULL, worker_thread, td);
123 BUG_ON(ret);
124 }
125
126 for (t = 0; t < nr_threads; t++) {
127 td = threads + t;
128
129 ret = pthread_join(td->pthread, NULL);
130 BUG_ON(ret);
131 }
132
133 } else {
134 pid = fork();
135 assert(pid >= 0);
136
137 if (!pid) {
138 worker_thread(threads + 0);
139 exit(0);
140 } else {
141 worker_thread(threads + 1);
142 }
143
144 retpid = waitpid(pid, &wait_stat, 0);
145 assert((retpid == pid) && WIFEXITED(wait_stat));
146 }
147
148 gettimeofday(&stop, NULL);
149 timersub(&stop, &start, &diff);
150
151 switch (bench_format) {
152 case BENCH_FORMAT_DEFAULT:
153 printf("# Executed %d pipe operations between two %s\n\n",
154 loops, threaded ? "threads" : "processes");
155
156 result_usec = diff.tv_sec * 1000000;
157 result_usec += diff.tv_usec;
158
159 printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
160 diff.tv_sec,
161 (unsigned long) (diff.tv_usec/1000));
162
163 printf(" %14lf usecs/op\n",
164 (double)result_usec / (double)loops);
165 printf(" %14d ops/sec\n",
166 (int)((double)loops /
167 ((double)result_usec / (double)1000000)));
168 break;
169
170 case BENCH_FORMAT_SIMPLE:
171 printf("%lu.%03lu\n",
172 diff.tv_sec,
173 (unsigned long) (diff.tv_usec / 1000));
174 break;
175
176 default:
177
178 fprintf(stderr, "Unknown format:%d\n", bench_format);
179 exit(1);
180 break;
181 }
182
183 return 0;
184}
185
