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-rw-r--r--tools/perf/bench/sched-pipe.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/tools/perf/bench/sched-pipe.c b/tools/perf/bench/sched-pipe.c
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+++ b/tools/perf/bench/sched-pipe.c
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+/*
+ *
+ * builtin-bench-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 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));
+ return 0;
+ }
+
+ switch (bench_format) {
+ case BENCH_FORMAT_DEFAULT:
+ printf("# Extecuted %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, 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, diff.tv_usec / 1000);
+ break;
+
+ default:
+ /* reaching here is something disaster */
+ fprintf(stderr, "Unknown format:%d\n", bench_format);
+ exit(1);
+ break;
+ }
+
+ return 0;
+}