128 lines
2.7 KiB
C
128 lines
2.7 KiB
C
/*
|
|
*
|
|
* 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>
|
|
|
|
#define LOOPS_DEFAULT 1000000
|
|
static int loops = LOOPS_DEFAULT;
|
|
|
|
static const struct option options[] = {
|
|
OPT_INTEGER('l', "loop", &loops,
|
|
"Specify number of loops"),
|
|
OPT_END()
|
|
};
|
|
|
|
static const char * const bench_sched_pipe_usage[] = {
|
|
"perf bench sched pipe <options>",
|
|
NULL
|
|
};
|
|
|
|
int bench_sched_pipe(int argc, const char **argv,
|
|
const char *prefix __used)
|
|
{
|
|
int pipe_1[2], pipe_2[2];
|
|
int m = 0, i;
|
|
struct timeval start, stop, diff;
|
|
unsigned long long result_usec = 0;
|
|
|
|
/*
|
|
* why does "ret" exist?
|
|
* discarding returned value of read(), write()
|
|
* causes error in building environment for perf
|
|
*/
|
|
int __used ret, wait_stat;
|
|
pid_t pid, retpid;
|
|
|
|
argc = parse_options(argc, argv, options,
|
|
bench_sched_pipe_usage, 0);
|
|
|
|
assert(!pipe(pipe_1));
|
|
assert(!pipe(pipe_2));
|
|
|
|
pid = fork();
|
|
assert(pid >= 0);
|
|
|
|
gettimeofday(&start, NULL);
|
|
|
|
if (!pid) {
|
|
for (i = 0; i < loops; i++) {
|
|
ret = read(pipe_1[0], &m, sizeof(int));
|
|
ret = write(pipe_2[1], &m, sizeof(int));
|
|
}
|
|
} else {
|
|
for (i = 0; i < loops; i++) {
|
|
ret = write(pipe_1[1], &m, sizeof(int));
|
|
ret = read(pipe_2[0], &m, sizeof(int));
|
|
}
|
|
}
|
|
|
|
gettimeofday(&stop, NULL);
|
|
timersub(&stop, &start, &diff);
|
|
|
|
if (pid) {
|
|
retpid = waitpid(pid, &wait_stat, 0);
|
|
assert((retpid == pid) && WIFEXITED(wait_stat));
|
|
} else {
|
|
exit(0);
|
|
}
|
|
|
|
switch (bench_format) {
|
|
case BENCH_FORMAT_DEFAULT:
|
|
printf("# Executed %d pipe operations between two tasks\n\n",
|
|
loops);
|
|
|
|
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;
|
|
}
|