1 | /* |
2 | * |
3 | * syscall.c |
4 | * |
5 | * syscall: Benchmark for system call performance |
6 | */ |
7 | #include "../perf.h" |
8 | #include "../util/util.h" |
9 | #include <subcmd/parse-options.h> |
10 | #include "../builtin.h" |
11 | #include "bench.h" |
12 | |
13 | #include <stdio.h> |
14 | #include <sys/time.h> |
15 | #include <sys/syscall.h> |
16 | #include <sys/types.h> |
17 | #include <sys/wait.h> |
18 | #include <unistd.h> |
19 | #include <stdlib.h> |
20 | |
21 | #ifndef __NR_fork |
22 | #define __NR_fork -1 |
23 | #endif |
24 | |
25 | #define LOOPS_DEFAULT 10000000 |
26 | static int loops = LOOPS_DEFAULT; |
27 | |
28 | static const struct option options[] = { |
29 | OPT_INTEGER('l', "loop" , &loops, "Specify number of loops" ), |
30 | OPT_END() |
31 | }; |
32 | |
33 | static const char * const bench_syscall_usage[] = { |
34 | "perf bench syscall <options>" , |
35 | NULL |
36 | }; |
37 | |
38 | static void test_fork(void) |
39 | { |
40 | pid_t pid = fork(); |
41 | |
42 | if (pid < 0) { |
43 | fprintf(stderr, "fork failed\n" ); |
44 | exit(1); |
45 | } else if (pid == 0) { |
46 | exit(0); |
47 | } else { |
48 | if (waitpid(pid, NULL, 0) < 0) { |
49 | fprintf(stderr, "waitpid failed\n" ); |
50 | exit(1); |
51 | } |
52 | } |
53 | } |
54 | |
55 | static void test_execve(void) |
56 | { |
57 | const char *pathname = "/bin/true" ; |
58 | char *const argv[] = { (char *)pathname, NULL }; |
59 | pid_t pid = fork(); |
60 | |
61 | if (pid < 0) { |
62 | fprintf(stderr, "fork failed\n" ); |
63 | exit(1); |
64 | } else if (pid == 0) { |
65 | execve(pathname, argv, NULL); |
66 | fprintf(stderr, "execve /bin/true failed\n" ); |
67 | exit(1); |
68 | } else { |
69 | if (waitpid(pid, NULL, 0) < 0) { |
70 | fprintf(stderr, "waitpid failed\n" ); |
71 | exit(1); |
72 | } |
73 | } |
74 | } |
75 | |
76 | static int bench_syscall_common(int argc, const char **argv, int syscall) |
77 | { |
78 | struct timeval start, stop, diff; |
79 | unsigned long long result_usec = 0; |
80 | const char *name = NULL; |
81 | int i; |
82 | |
83 | argc = parse_options(argc, argv, options, bench_syscall_usage, 0); |
84 | |
85 | gettimeofday(&start, NULL); |
86 | |
87 | for (i = 0; i < loops; i++) { |
88 | switch (syscall) { |
89 | case __NR_getppid: |
90 | getppid(); |
91 | break; |
92 | case __NR_getpgid: |
93 | getpgid(0); |
94 | break; |
95 | case __NR_fork: |
96 | test_fork(); |
97 | /* Only loop 10000 times to save time */ |
98 | if (i == 10000) |
99 | loops = 10000; |
100 | break; |
101 | case __NR_execve: |
102 | test_execve(); |
103 | /* Only loop 10000 times to save time */ |
104 | if (i == 10000) |
105 | loops = 10000; |
106 | break; |
107 | default: |
108 | break; |
109 | } |
110 | } |
111 | |
112 | gettimeofday(&stop, NULL); |
113 | timersub(&stop, &start, &diff); |
114 | |
115 | switch (syscall) { |
116 | case __NR_getppid: |
117 | name = "getppid()" ; |
118 | break; |
119 | case __NR_getpgid: |
120 | name = "getpgid()" ; |
121 | break; |
122 | case __NR_fork: |
123 | name = "fork()" ; |
124 | break; |
125 | case __NR_execve: |
126 | name = "execve()" ; |
127 | break; |
128 | default: |
129 | break; |
130 | } |
131 | |
132 | switch (bench_format) { |
133 | case BENCH_FORMAT_DEFAULT: |
134 | printf("# Executed %'d %s calls\n" , loops, name); |
135 | |
136 | result_usec = diff.tv_sec * 1000000; |
137 | result_usec += diff.tv_usec; |
138 | |
139 | printf(" %14s: %lu.%03lu [sec]\n\n" , "Total time" , |
140 | (unsigned long) diff.tv_sec, |
141 | (unsigned long) (diff.tv_usec/1000)); |
142 | |
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))); |
148 | break; |
149 | |
150 | case BENCH_FORMAT_SIMPLE: |
151 | printf("%lu.%03lu\n" , |
152 | (unsigned long) diff.tv_sec, |
153 | (unsigned long) (diff.tv_usec / 1000)); |
154 | break; |
155 | |
156 | default: |
157 | /* reaching here is something disaster */ |
158 | fprintf(stderr, "Unknown format:%d\n" , bench_format); |
159 | exit(1); |
160 | break; |
161 | } |
162 | |
163 | return 0; |
164 | } |
165 | |
166 | int bench_syscall_basic(int argc, const char **argv) |
167 | { |
168 | return bench_syscall_common(argc, argv, syscall: __NR_getppid); |
169 | } |
170 | |
171 | int bench_syscall_getpgid(int argc, const char **argv) |
172 | { |
173 | return bench_syscall_common(argc, argv, syscall: __NR_getpgid); |
174 | } |
175 | |
176 | int bench_syscall_fork(int argc, const char **argv) |
177 | { |
178 | return bench_syscall_common(argc, argv, __NR_fork); |
179 | } |
180 | |
181 | int bench_syscall_execve(int argc, const char **argv) |
182 | { |
183 | return bench_syscall_common(argc, argv, syscall: __NR_execve); |
184 | } |
185 | |