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/libbpf.h> 22 23 #define MAX_CNT 1000000 24 25 static struct bpf_link *links[2]; 26 static struct bpf_object *obj; 27 static int cnt; 28 29 static __u64 time_get_ns(void) 30 { 31 struct timespec ts; 32 33 clock_gettime(CLOCK_MONOTONIC, &ts); 34 return ts.tv_sec * 1000000000ull + ts.tv_nsec; 35 } 36 37 static void test_task_rename(int cpu) 38 { 39 __u64 start_time; 40 char buf[] = "test\n"; 41 int i, fd; 42 43 fd = open("/proc/self/comm", O_WRONLY|O_TRUNC); 44 if (fd < 0) { 45 printf("couldn't open /proc\n"); 46 exit(1); 47 } 48 start_time = time_get_ns(); 49 for (i = 0; i < MAX_CNT; i++) { 50 if (write(fd, buf, sizeof(buf)) < 0) { 51 printf("task rename failed: %s\n", strerror(errno)); 52 close(fd); 53 return; 54 } 55 } 56 printf("task_rename:%d: %lld events per sec\n", 57 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); 58 close(fd); 59 } 60 61 static void test_urandom_read(int cpu) 62 { 63 __u64 start_time; 64 char buf[4]; 65 int i, fd; 66 67 fd = open("/dev/urandom", O_RDONLY); 68 if (fd < 0) { 69 printf("couldn't open /dev/urandom\n"); 70 exit(1); 71 } 72 start_time = time_get_ns(); 73 for (i = 0; i < MAX_CNT; i++) { 74 if (read(fd, buf, sizeof(buf)) < 0) { 75 printf("failed to read from /dev/urandom: %s\n", strerror(errno)); 76 close(fd); 77 return; 78 } 79 } 80 printf("urandom_read:%d: %lld events per sec\n", 81 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); 82 close(fd); 83 } 84 85 static void loop(int cpu, int flags) 86 { 87 cpu_set_t cpuset; 88 89 CPU_ZERO(&cpuset); 90 CPU_SET(cpu, &cpuset); 91 sched_setaffinity(0, sizeof(cpuset), &cpuset); 92 93 if (flags & 1) 94 test_task_rename(cpu); 95 if (flags & 2) 96 test_urandom_read(cpu); 97 } 98 99 static void run_perf_test(int tasks, int flags) 100 { 101 pid_t pid[tasks]; 102 int i; 103 104 for (i = 0; i < tasks; i++) { 105 pid[i] = fork(); 106 if (pid[i] == 0) { 107 loop(i, flags); 108 exit(0); 109 } else if (pid[i] == -1) { 110 printf("couldn't spawn #%d process\n", i); 111 exit(1); 112 } 113 } 114 for (i = 0; i < tasks; i++) { 115 int status; 116 117 assert(waitpid(pid[i], &status, 0) == pid[i]); 118 assert(status == 0); 119 } 120 } 121 122 static int load_progs(char *filename) 123 { 124 struct bpf_program *prog; 125 int err = 0; 126 127 obj = bpf_object__open_file(filename, NULL); 128 err = libbpf_get_error(obj); 129 if (err < 0) { 130 fprintf(stderr, "ERROR: opening BPF object file failed\n"); 131 return err; 132 } 133 134 /* load BPF program */ 135 err = bpf_object__load(obj); 136 if (err < 0) { 137 fprintf(stderr, "ERROR: loading BPF object file failed\n"); 138 return err; 139 } 140 141 bpf_object__for_each_program(prog, obj) { 142 links[cnt] = bpf_program__attach(prog); 143 err = libbpf_get_error(links[cnt]); 144 if (err < 0) { 145 fprintf(stderr, "ERROR: bpf_program__attach failed\n"); 146 links[cnt] = NULL; 147 return err; 148 } 149 cnt++; 150 } 151 152 return err; 153 } 154 155 static void unload_progs(void) 156 { 157 while (cnt) 158 bpf_link__destroy(links[--cnt]); 159 160 bpf_object__close(obj); 161 } 162 163 int main(int argc, char **argv) 164 { 165 int num_cpu = sysconf(_SC_NPROCESSORS_ONLN); 166 int test_flags = ~0; 167 char filename[256]; 168 int err = 0; 169 170 171 if (argc > 1) 172 test_flags = atoi(argv[1]) ? : test_flags; 173 if (argc > 2) 174 num_cpu = atoi(argv[2]) ? : num_cpu; 175 176 if (test_flags & 0x3) { 177 printf("BASE\n"); 178 run_perf_test(num_cpu, test_flags); 179 } 180 181 if (test_flags & 0xC) { 182 snprintf(filename, sizeof(filename), 183 "%s_kprobe_kern.o", argv[0]); 184 185 printf("w/KPROBE\n"); 186 err = load_progs(filename); 187 if (!err) 188 run_perf_test(num_cpu, test_flags >> 2); 189 190 unload_progs(); 191 } 192 193 if (test_flags & 0x30) { 194 snprintf(filename, sizeof(filename), 195 "%s_tp_kern.o", argv[0]); 196 printf("w/TRACEPOINT\n"); 197 err = load_progs(filename); 198 if (!err) 199 run_perf_test(num_cpu, test_flags >> 4); 200 201 unload_progs(); 202 } 203 204 if (test_flags & 0xC0) { 205 snprintf(filename, sizeof(filename), 206 "%s_raw_tp_kern.o", argv[0]); 207 printf("w/RAW_TRACEPOINT\n"); 208 err = load_progs(filename); 209 if (!err) 210 run_perf_test(num_cpu, test_flags >> 6); 211 212 unload_progs(); 213 } 214 215 return err; 216 } 217