sched-pipe.c
3.84 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
*
* sched-pipe.c
*
* pipe: Benchmark for pipe()
*
* Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com>
* http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c
* Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
*/
#include "../perf.h"
#include "../util/util.h"
#include "../util/parse-options.h"
#include "../builtin.h"
#include "bench.h"
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/wait.h>
#include <linux/unistd.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <sys/time.h>
#include <sys/types.h>
#include <pthread.h>
struct thread_data {
int nr;
int pipe_read;
int pipe_write;
pthread_t pthread;
};
#define LOOPS_DEFAULT 1000000
static int loops = LOOPS_DEFAULT;
/* Use processes by default: */
static bool threaded;
static const struct option options[] = {
OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
OPT_BOOLEAN('T', "threaded", &threaded, "Specify threads/process based task setup"),
OPT_END()
};
static const char * const bench_sched_pipe_usage[] = {
"perf bench sched pipe <options>",
NULL
};
static void *worker_thread(void *__tdata)
{
struct thread_data *td = __tdata;
int m = 0, i;
int ret;
for (i = 0; i < loops; i++) {
if (!td->nr) {
ret = read(td->pipe_read, &m, sizeof(int));
BUG_ON(ret != sizeof(int));
ret = write(td->pipe_write, &m, sizeof(int));
BUG_ON(ret != sizeof(int));
} else {
ret = write(td->pipe_write, &m, sizeof(int));
BUG_ON(ret != sizeof(int));
ret = read(td->pipe_read, &m, sizeof(int));
BUG_ON(ret != sizeof(int));
}
}
return NULL;
}
int bench_sched_pipe(int argc, const char **argv, const char *prefix __maybe_unused)
{
struct thread_data threads[2], *td;
int pipe_1[2], pipe_2[2];
struct timeval start, stop, diff;
unsigned long long result_usec = 0;
int nr_threads = 2;
int t;
/*
* why does "ret" exist?
* discarding returned value of read(), write()
* causes error in building environment for perf
*/
int __maybe_unused ret, wait_stat;
pid_t pid, retpid __maybe_unused;
argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0);
BUG_ON(pipe(pipe_1));
BUG_ON(pipe(pipe_2));
gettimeofday(&start, NULL);
for (t = 0; t < nr_threads; t++) {
td = threads + t;
td->nr = t;
if (t == 0) {
td->pipe_read = pipe_1[0];
td->pipe_write = pipe_2[1];
} else {
td->pipe_write = pipe_1[1];
td->pipe_read = pipe_2[0];
}
}
if (threaded) {
for (t = 0; t < nr_threads; t++) {
td = threads + t;
ret = pthread_create(&td->pthread, NULL, worker_thread, td);
BUG_ON(ret);
}
for (t = 0; t < nr_threads; t++) {
td = threads + t;
ret = pthread_join(td->pthread, NULL);
BUG_ON(ret);
}
} else {
pid = fork();
assert(pid >= 0);
if (!pid) {
worker_thread(threads + 0);
exit(0);
} else {
worker_thread(threads + 1);
}
retpid = waitpid(pid, &wait_stat, 0);
assert((retpid == pid) && WIFEXITED(wait_stat));
}
gettimeofday(&stop, NULL);
timersub(&stop, &start, &diff);
switch (bench_format) {
case BENCH_FORMAT_DEFAULT:
printf("# Executed %d pipe operations between two %s\n\n",
loops, threaded ? "threads" : "processes");
result_usec = diff.tv_sec * 1000000;
result_usec += diff.tv_usec;
printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
diff.tv_sec,
(unsigned long) (diff.tv_usec/1000));
printf(" %14lf usecs/op\n",
(double)result_usec / (double)loops);
printf(" %14d ops/sec\n",
(int)((double)loops /
((double)result_usec / (double)1000000)));
break;
case BENCH_FORMAT_SIMPLE:
printf("%lu.%03lu\n",
diff.tv_sec,
(unsigned long) (diff.tv_usec / 1000));
break;
default:
/* reaching here is something disaster */
fprintf(stderr, "Unknown format:%d\n", bench_format);
exit(1);
break;
}
return 0;
}