5 * syscall: Benchmark for system call performance
8 #include "../util/util.h"
9 #include <subcmd/parse-options.h>
10 #include "../builtin.h"
15 #include <sys/syscall.h>
16 #include <sys/types.h>
25 #define LOOPS_DEFAULT 10000000
26 static int loops = LOOPS_DEFAULT;
28 static const struct option options[] = {
29 OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
33 static const char * const bench_syscall_usage[] = {
34 "perf bench syscall <options>",
38 static void test_fork(void)
43 fprintf(stderr, "fork failed\n");
45 } else if (pid == 0) {
48 if (waitpid(pid, NULL, 0) < 0) {
49 fprintf(stderr, "waitpid failed\n");
55 static void test_execve(void)
57 const char *pathname = "/bin/true";
58 char *const argv[] = { (char *)pathname, NULL };
62 fprintf(stderr, "fork failed\n");
64 } else if (pid == 0) {
65 execve(pathname, argv, NULL);
66 fprintf(stderr, "execve /bin/true failed\n");
69 if (waitpid(pid, NULL, 0) < 0) {
70 fprintf(stderr, "waitpid failed\n");
76 static int bench_syscall_common(int argc, const char **argv, int syscall)
78 struct timeval start, stop, diff;
79 unsigned long long result_usec = 0;
80 const char *name = NULL;
83 argc = parse_options(argc, argv, options, bench_syscall_usage, 0);
85 gettimeofday(&start, NULL);
87 for (i = 0; i < loops; i++) {
97 /* Only loop 10000 times to save time */
103 /* Only loop 10000 times to save time */
112 gettimeofday(&stop, NULL);
113 timersub(&stop, &start, &diff);
132 switch (bench_format) {
133 case BENCH_FORMAT_DEFAULT:
134 printf("# Executed %'d %s calls\n", loops, name);
136 result_usec = diff.tv_sec * 1000000;
137 result_usec += diff.tv_usec;
139 printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
140 (unsigned long) diff.tv_sec,
141 (unsigned long) (diff.tv_usec/1000));
143 printf(" %14lf usecs/op\n",
144 (double)result_usec / (double)loops);
145 printf(" %'14d ops/sec\n",
146 (int)((double)loops /
147 ((double)result_usec / (double)1000000)));
150 case BENCH_FORMAT_SIMPLE:
151 printf("%lu.%03lu\n",
152 (unsigned long) diff.tv_sec,
153 (unsigned long) (diff.tv_usec / 1000));
157 /* reaching here is something disaster */
158 fprintf(stderr, "Unknown format:%d\n", bench_format);
166 int bench_syscall_basic(int argc, const char **argv)
168 return bench_syscall_common(argc, argv, __NR_getppid);
171 int bench_syscall_getpgid(int argc, const char **argv)
173 return bench_syscall_common(argc, argv, __NR_getpgid);
176 int bench_syscall_fork(int argc, const char **argv)
178 return bench_syscall_common(argc, argv, __NR_fork);
181 int bench_syscall_execve(int argc, const char **argv)
183 return bench_syscall_common(argc, argv, __NR_execve);