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Hitoshi Mitakec7d93002009-11-05 09:31:33 +09001/*
2 *
3 * builtin-bench-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>
Hitoshi Mitake5ff0cfc2009-11-09 12:31:05 +090029#include <sys/types.h>
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090030
31#define LOOPS_DEFAULT 1000000
32static int loops = LOOPS_DEFAULT;
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090033
34static const struct option options[] = {
35 OPT_INTEGER('l', "loop", &loops,
36 "Specify number of loops"),
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090037 OPT_END()
38};
39
40static const char * const bench_sched_pipe_usage[] = {
41 "perf bench sched pipe <options>",
42 NULL
43};
44
45int bench_sched_pipe(int argc, const char **argv,
46 const char *prefix __used)
47{
48 int pipe_1[2], pipe_2[2];
49 int m = 0, i;
50 struct timeval start, stop, diff;
51 unsigned long long result_usec = 0;
52
53 /*
54 * why does "ret" exist?
55 * discarding returned value of read(), write()
56 * causes error in building environment for perf
57 */
Hitoshi Mitake5ff0cfc2009-11-09 12:31:05 +090058 int ret, wait_stat;
59 pid_t pid, retpid;
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090060
61 argc = parse_options(argc, argv, options,
62 bench_sched_pipe_usage, 0);
63
64 assert(!pipe(pipe_1));
65 assert(!pipe(pipe_2));
66
67 pid = fork();
68 assert(pid >= 0);
69
70 gettimeofday(&start, NULL);
71
72 if (!pid) {
73 for (i = 0; i < loops; i++) {
74 ret = read(pipe_1[0], &m, sizeof(int));
75 ret = write(pipe_2[1], &m, sizeof(int));
76 }
77 } else {
78 for (i = 0; i < loops; i++) {
79 ret = write(pipe_1[1], &m, sizeof(int));
80 ret = read(pipe_2[0], &m, sizeof(int));
81 }
82 }
83
84 gettimeofday(&stop, NULL);
85 timersub(&stop, &start, &diff);
86
Hitoshi Mitake5ff0cfc2009-11-09 12:31:05 +090087 if (pid) {
88 retpid = waitpid(pid, &wait_stat, 0);
89 assert((retpid == pid) && WIFEXITED(wait_stat));
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090090 return 0;
Hitoshi Mitake5ff0cfc2009-11-09 12:31:05 +090091 }
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090092
Hitoshi Mitake158ba822009-11-10 08:20:02 +090093 switch (bench_format) {
94 case BENCH_FORMAT_DEFAULT:
Hitoshi Mitakec7d93002009-11-05 09:31:33 +090095 printf("(executing %d pipe operations between two tasks)\n\n",
96 loops);
97
98 result_usec = diff.tv_sec * 1000000;
99 result_usec += diff.tv_usec;
100
101 printf("\tTotal time:%lu.%03lu sec\n",
102 diff.tv_sec, diff.tv_usec / 1000);
103 printf("\t\t%lf usecs/op\n",
104 (double)result_usec / (double)loops);
105 printf("\t\t%d ops/sec\n",
106 (int)((double)loops /
107 ((double)result_usec / (double)1000000)));
Hitoshi Mitake158ba822009-11-10 08:20:02 +0900108 break;
109
110 case BENCH_FORMAT_SIMPLE:
111 printf("%lu.%03lu\n",
112 diff.tv_sec, diff.tv_usec / 1000);
113 break;
114
115 default:
116 /* reaching here is something disaster */
117 fprintf(stderr, "Unknown format:%d\n", bench_format);
118 exit(1);
119 break;
Hitoshi Mitakec7d93002009-11-05 09:31:33 +0900120 }
121
122 return 0;
123}