1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2016 Facebook
3  */
4 #define _GNU_SOURCE
5 #include <sched.h>
6 #include <errno.h>
7 #include <stdio.h>
8 #include <sys/types.h>
9 #include <asm/unistd.h>
10 #include <fcntl.h>
11 #include <unistd.h>
12 #include <assert.h>
13 #include <sys/wait.h>
14 #include <stdlib.h>
15 #include <signal.h>
16 #include <linux/bpf.h>
17 #include <string.h>
18 #include <time.h>
19 #include <sys/resource.h>
20 #include <bpf/bpf.h>
21 #include "bpf_load.h"
22 
23 #define MAX_CNT 1000000
24 
25 static __u64 time_get_ns(void)
26 {
27 	struct timespec ts;
28 
29 	clock_gettime(CLOCK_MONOTONIC, &ts);
30 	return ts.tv_sec * 1000000000ull + ts.tv_nsec;
31 }
32 
33 static void test_task_rename(int cpu)
34 {
35 	__u64 start_time;
36 	char buf[] = "test\n";
37 	int i, fd;
38 
39 	fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
40 	if (fd < 0) {
41 		printf("couldn't open /proc\n");
42 		exit(1);
43 	}
44 	start_time = time_get_ns();
45 	for (i = 0; i < MAX_CNT; i++) {
46 		if (write(fd, buf, sizeof(buf)) < 0) {
47 			printf("task rename failed: %s\n", strerror(errno));
48 			close(fd);
49 			return;
50 		}
51 	}
52 	printf("task_rename:%d: %lld events per sec\n",
53 	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
54 	close(fd);
55 }
56 
57 static void test_urandom_read(int cpu)
58 {
59 	__u64 start_time;
60 	char buf[4];
61 	int i, fd;
62 
63 	fd = open("/dev/urandom", O_RDONLY);
64 	if (fd < 0) {
65 		printf("couldn't open /dev/urandom\n");
66 		exit(1);
67 	}
68 	start_time = time_get_ns();
69 	for (i = 0; i < MAX_CNT; i++) {
70 		if (read(fd, buf, sizeof(buf)) < 0) {
71 			printf("failed to read from /dev/urandom: %s\n", strerror(errno));
72 			close(fd);
73 			return;
74 		}
75 	}
76 	printf("urandom_read:%d: %lld events per sec\n",
77 	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
78 	close(fd);
79 }
80 
81 static void loop(int cpu, int flags)
82 {
83 	cpu_set_t cpuset;
84 
85 	CPU_ZERO(&cpuset);
86 	CPU_SET(cpu, &cpuset);
87 	sched_setaffinity(0, sizeof(cpuset), &cpuset);
88 
89 	if (flags & 1)
90 		test_task_rename(cpu);
91 	if (flags & 2)
92 		test_urandom_read(cpu);
93 }
94 
95 static void run_perf_test(int tasks, int flags)
96 {
97 	pid_t pid[tasks];
98 	int i;
99 
100 	for (i = 0; i < tasks; i++) {
101 		pid[i] = fork();
102 		if (pid[i] == 0) {
103 			loop(i, flags);
104 			exit(0);
105 		} else if (pid[i] == -1) {
106 			printf("couldn't spawn #%d process\n", i);
107 			exit(1);
108 		}
109 	}
110 	for (i = 0; i < tasks; i++) {
111 		int status;
112 
113 		assert(waitpid(pid[i], &status, 0) == pid[i]);
114 		assert(status == 0);
115 	}
116 }
117 
118 static void unload_progs(void)
119 {
120 	close(prog_fd[0]);
121 	close(prog_fd[1]);
122 	close(event_fd[0]);
123 	close(event_fd[1]);
124 }
125 
126 int main(int argc, char **argv)
127 {
128 	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
129 	char filename[256];
130 	int num_cpu = 8;
131 	int test_flags = ~0;
132 
133 	setrlimit(RLIMIT_MEMLOCK, &r);
134 
135 	if (argc > 1)
136 		test_flags = atoi(argv[1]) ? : test_flags;
137 	if (argc > 2)
138 		num_cpu = atoi(argv[2]) ? : num_cpu;
139 
140 	if (test_flags & 0x3) {
141 		printf("BASE\n");
142 		run_perf_test(num_cpu, test_flags);
143 	}
144 
145 	if (test_flags & 0xC) {
146 		snprintf(filename, sizeof(filename),
147 			 "%s_kprobe_kern.o", argv[0]);
148 		if (load_bpf_file(filename)) {
149 			printf("%s", bpf_log_buf);
150 			return 1;
151 		}
152 		printf("w/KPROBE\n");
153 		run_perf_test(num_cpu, test_flags >> 2);
154 		unload_progs();
155 	}
156 
157 	if (test_flags & 0x30) {
158 		snprintf(filename, sizeof(filename),
159 			 "%s_tp_kern.o", argv[0]);
160 		if (load_bpf_file(filename)) {
161 			printf("%s", bpf_log_buf);
162 			return 1;
163 		}
164 		printf("w/TRACEPOINT\n");
165 		run_perf_test(num_cpu, test_flags >> 4);
166 		unload_progs();
167 	}
168 
169 	if (test_flags & 0xC0) {
170 		snprintf(filename, sizeof(filename),
171 			 "%s_raw_tp_kern.o", argv[0]);
172 		if (load_bpf_file(filename)) {
173 			printf("%s", bpf_log_buf);
174 			return 1;
175 		}
176 		printf("w/RAW_TRACEPOINT\n");
177 		run_perf_test(num_cpu, test_flags >> 6);
178 		unload_progs();
179 	}
180 
181 	return 0;
182 }
183