1 /*
2 *
3 * sched-pipe.c
4 *
5 * pipe: Benchmark for pipe()
6 *
7 * Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com>
8 * http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c
9 * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
10 *
11 */
12
13 #include "../perf.h"
14 #include "../util/util.h"
15 #include "../util/parse-options.h"
16 #include "../builtin.h"
17 #include "bench.h"
18
19 #include <unistd.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <signal.h>
23 #include <sys/wait.h>
24 #include <linux/unistd.h>
25 #include <string.h>
26 #include <errno.h>
27 #include <assert.h>
28 #include <sys/time.h>
29 #include <sys/types.h>
30
31 #define LOOPS_DEFAULT 1000000
32 static int loops = LOOPS_DEFAULT;
33
34 static const struct option options[] = {
35 OPT_INTEGER('l', "loop", &loops,
36 "Specify number of loops"),
37 OPT_END()
38 };
39
40 static const char * const bench_sched_pipe_usage[] = {
41 "perf bench sched pipe <options>",
42 NULL
43 };
44
bench_sched_pipe(int argc,const char ** argv,const char * prefix __used)45 int bench_sched_pipe(int argc, const char **argv,
46 const char *prefix __used)
47 {
48 /* ANDROID_CHANGE_BEGIN */
49 #ifndef __BIONIC__
50 int pipe_1[2], pipe_2[2];
51 int m = 0, i;
52 struct timeval start, stop, diff;
53 unsigned long long result_usec = 0;
54
55 /*
56 * why does "ret" exist?
57 * discarding returned value of read(), write()
58 * causes error in building environment for perf
59 */
60 int __used ret, wait_stat;
61 pid_t pid, retpid;
62
63 argc = parse_options(argc, argv, options,
64 bench_sched_pipe_usage, 0);
65
66 assert(!pipe(pipe_1));
67 assert(!pipe(pipe_2));
68
69 pid = fork();
70 assert(pid >= 0);
71
72 gettimeofday(&start, NULL);
73
74 if (!pid) {
75 for (i = 0; i < loops; i++) {
76 ret = read(pipe_1[0], &m, sizeof(int));
77 ret = write(pipe_2[1], &m, sizeof(int));
78 }
79 } else {
80 for (i = 0; i < loops; i++) {
81 ret = write(pipe_1[1], &m, sizeof(int));
82 ret = read(pipe_2[0], &m, sizeof(int));
83 }
84 }
85
86 gettimeofday(&stop, NULL);
87 timersub(&stop, &start, &diff);
88
89 if (pid) {
90 retpid = waitpid(pid, &wait_stat, 0);
91 assert((retpid == pid) && WIFEXITED(wait_stat));
92 } else {
93 exit(0);
94 }
95
96 switch (bench_format) {
97 case BENCH_FORMAT_DEFAULT:
98 printf("# Executed %d pipe operations between two tasks\n\n",
99 loops);
100
101 result_usec = diff.tv_sec * 1000000;
102 result_usec += diff.tv_usec;
103
104 printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
105 diff.tv_sec,
106 (unsigned long) (diff.tv_usec/1000));
107
108 printf(" %14lf usecs/op\n",
109 (double)result_usec / (double)loops);
110 printf(" %14d ops/sec\n",
111 (int)((double)loops /
112 ((double)result_usec / (double)1000000)));
113 break;
114
115 case BENCH_FORMAT_SIMPLE:
116 printf("%lu.%03lu\n",
117 diff.tv_sec,
118 (unsigned long) (diff.tv_usec / 1000));
119 break;
120
121 default:
122 /* reaching here is something disaster */
123 fprintf(stderr, "Unknown format:%d\n", bench_format);
124 exit(1);
125 break;
126 }
127 #endif
128 /* ANDROID_CHANGE_END */
129
130 return 0;
131 }
132