Blame view

samples/bpf/test_overhead_user.c 3.44 KB
e3edfdec0   Alexei Starovoitov   samples/bpf: add ...
1
2
3
4
5
6
7
8
  /* Copyright (c) 2016 Facebook
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of version 2 of the GNU General Public
   * License as published by the Free Software Foundation.
   */
  #define _GNU_SOURCE
  #include <sched.h>
f599525df   Taeung Song   samples/bpf: Chec...
9
  #include <errno.h>
e3edfdec0   Alexei Starovoitov   samples/bpf: add ...
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
  #include <stdio.h>
  #include <sys/types.h>
  #include <asm/unistd.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <assert.h>
  #include <sys/wait.h>
  #include <stdlib.h>
  #include <signal.h>
  #include <linux/bpf.h>
  #include <string.h>
  #include <time.h>
  #include <sys/resource.h>
  #include "libbpf.h"
  #include "bpf_load.h"
  
  #define MAX_CNT 1000000
  
  static __u64 time_get_ns(void)
  {
  	struct timespec ts;
  
  	clock_gettime(CLOCK_MONOTONIC, &ts);
  	return ts.tv_sec * 1000000000ull + ts.tv_nsec;
  }
  
  static void test_task_rename(int cpu)
  {
  	__u64 start_time;
  	char buf[] = "test
  ";
  	int i, fd;
  
  	fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
  	if (fd < 0) {
  		printf("couldn't open /proc
  ");
  		exit(1);
  	}
  	start_time = time_get_ns();
f599525df   Taeung Song   samples/bpf: Chec...
50
51
52
53
54
55
56
57
  	for (i = 0; i < MAX_CNT; i++) {
  		if (write(fd, buf, sizeof(buf)) < 0) {
  			printf("task rename failed: %s
  ", strerror(errno));
  			close(fd);
  			return;
  		}
  	}
e3edfdec0   Alexei Starovoitov   samples/bpf: add ...
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
  	printf("task_rename:%d: %lld events per sec
  ",
  	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
  	close(fd);
  }
  
  static void test_urandom_read(int cpu)
  {
  	__u64 start_time;
  	char buf[4];
  	int i, fd;
  
  	fd = open("/dev/urandom", O_RDONLY);
  	if (fd < 0) {
  		printf("couldn't open /dev/urandom
  ");
  		exit(1);
  	}
  	start_time = time_get_ns();
f599525df   Taeung Song   samples/bpf: Chec...
77
78
79
80
81
82
83
84
  	for (i = 0; i < MAX_CNT; i++) {
  		if (read(fd, buf, sizeof(buf)) < 0) {
  			printf("failed to read from /dev/urandom: %s
  ", strerror(errno));
  			close(fd);
  			return;
  		}
  	}
e3edfdec0   Alexei Starovoitov   samples/bpf: add ...
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
  	printf("urandom_read:%d: %lld events per sec
  ",
  	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
  	close(fd);
  }
  
  static void loop(int cpu, int flags)
  {
  	cpu_set_t cpuset;
  
  	CPU_ZERO(&cpuset);
  	CPU_SET(cpu, &cpuset);
  	sched_setaffinity(0, sizeof(cpuset), &cpuset);
  
  	if (flags & 1)
  		test_task_rename(cpu);
  	if (flags & 2)
  		test_urandom_read(cpu);
  }
  
  static void run_perf_test(int tasks, int flags)
  {
  	pid_t pid[tasks];
  	int i;
  
  	for (i = 0; i < tasks; i++) {
  		pid[i] = fork();
  		if (pid[i] == 0) {
  			loop(i, flags);
  			exit(0);
  		} else if (pid[i] == -1) {
  			printf("couldn't spawn #%d process
  ", i);
  			exit(1);
  		}
  	}
  	for (i = 0; i < tasks; i++) {
  		int status;
  
  		assert(waitpid(pid[i], &status, 0) == pid[i]);
  		assert(status == 0);
  	}
  }
  
  static void unload_progs(void)
  {
  	close(prog_fd[0]);
  	close(prog_fd[1]);
  	close(event_fd[0]);
  	close(event_fd[1]);
  }
  
  int main(int argc, char **argv)
  {
  	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
  	char filename[256];
  	int num_cpu = 8;
  	int test_flags = ~0;
  
  	setrlimit(RLIMIT_MEMLOCK, &r);
  
  	if (argc > 1)
  		test_flags = atoi(argv[1]) ? : test_flags;
  	if (argc > 2)
  		num_cpu = atoi(argv[2]) ? : num_cpu;
  
  	if (test_flags & 0x3) {
  		printf("BASE
  ");
  		run_perf_test(num_cpu, test_flags);
  	}
  
  	if (test_flags & 0xC) {
  		snprintf(filename, sizeof(filename),
  			 "%s_kprobe_kern.o", argv[0]);
  		if (load_bpf_file(filename)) {
  			printf("%s", bpf_log_buf);
  			return 1;
  		}
  		printf("w/KPROBE
  ");
  		run_perf_test(num_cpu, test_flags >> 2);
  		unload_progs();
  	}
  
  	if (test_flags & 0x30) {
  		snprintf(filename, sizeof(filename),
  			 "%s_tp_kern.o", argv[0]);
  		if (load_bpf_file(filename)) {
  			printf("%s", bpf_log_buf);
  			return 1;
  		}
  		printf("w/TRACEPOINT
  ");
  		run_perf_test(num_cpu, test_flags >> 4);
  		unload_progs();
  	}
  
  	return 0;
  }