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| -rw-r--r-- | tools/perf/bench/sched-pipe.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/tools/perf/bench/sched-pipe.c b/tools/perf/bench/sched-pipe.c new file mode 100644 index 00000000000..3214ed20b1a --- /dev/null +++ b/tools/perf/bench/sched-pipe.c @@ -0,0 +1,113 @@ +/* + * + * 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> + +#define LOOPS_DEFAULT 1000000 +static int loops = LOOPS_DEFAULT; +static int simple = 0; + +static const struct option options[] = { + OPT_INTEGER('l', "loop", &loops, + "Specify number of loops"), + OPT_BOOLEAN('s', "simple-output", &simple, + "Do simple output (this maybe useful for" + "processing by scripts or graph tools like gnuplot)"), + 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; + pid_t pid; + + 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) + return 0; + + if (simple) + printf("%lu.%03lu\n", + diff.tv_sec, diff.tv_usec / 1000); + else { + printf("(executing %d pipe operations between two tasks)\n\n", + loops); + + result_usec = diff.tv_sec * 1000000; + result_usec += diff.tv_usec; + + printf("\tTotal time:%lu.%03lu sec\n", + diff.tv_sec, diff.tv_usec / 1000); + printf("\t\t%lf usecs/op\n", + (double)result_usec / (double)loops); + printf("\t\t%d ops/sec\n", + (int)((double)loops / + ((double)result_usec / (double)1000000))); + } + + return 0; +} |