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 <bpf/bpf.h> 20 #include <bpf/libbpf.h> 21 22 #define MAX_CNT 1000000 23 24 static struct bpf_link *links[2]; 25 static struct bpf_object *obj; 26 static int cnt; 27 28 static __u64 time_get_ns(void) 29 { 30 struct timespec ts; 31 32 clock_gettime(CLOCK_MONOTONIC, &ts); 33 return ts.tv_sec * 1000000000ull + ts.tv_nsec; 34 } 35 36 static void test_task_rename(int cpu) 37 { 38 __u64 start_time; 39 char buf[] = "test\n"; 40 int i, fd; 41 42 fd = open("/proc/self/comm", O_WRONLY|O_TRUNC); 43 if (fd < 0) { 44 printf("couldn't open /proc\n"); 45 exit(1); 46 } 47 start_time = time_get_ns(); 48 for (i = 0; i < MAX_CNT; i++) { 49 if (write(fd, buf, sizeof(buf)) < 0) { 50 printf("task rename failed: %s\n", strerror(errno)); 51 close(fd); 52 return; 53 } 54 } 55 printf("task_rename:%d: %lld events per sec\n", 56 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); 57 close(fd); 58 } 59 60 static void test_urandom_read(int cpu) 61 { 62 __u64 start_time; 63 char buf[4]; 64 int i, fd; 65 66 fd = open("/dev/urandom", O_RDONLY); 67 if (fd < 0) { 68 printf("couldn't open /dev/urandom\n"); 69 exit(1); 70 } 71 start_time = time_get_ns(); 72 for (i = 0; i < MAX_CNT; i++) { 73 if (read(fd, buf, sizeof(buf)) < 0) { 74 printf("failed to read from /dev/urandom: %s\n", strerror(errno)); 75 close(fd); 76 return; 77 } 78 } 79 printf("urandom_read:%d: %lld events per sec\n", 80 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); 81 close(fd); 82 } 83 84 static void loop(int cpu, int flags) 85 { 86 cpu_set_t cpuset; 87 88 CPU_ZERO(&cpuset); 89 CPU_SET(cpu, &cpuset); 90 sched_setaffinity(0, sizeof(cpuset), &cpuset); 91 92 if (flags & 1) 93 test_task_rename(cpu); 94 if (flags & 2) 95 test_urandom_read(cpu); 96 } 97 98 static void run_perf_test(int tasks, int flags) 99 { 100 pid_t pid[tasks]; 101 int i; 102 103 for (i = 0; i < tasks; i++) { 104 pid[i] = fork(); 105 if (pid[i] == 0) { 106 loop(i, flags); 107 exit(0); 108 } else if (pid[i] == -1) { 109 printf("couldn't spawn #%d process\n", i); 110 exit(1); 111 } 112 } 113 for (i = 0; i < tasks; i++) { 114 int status; 115 116 assert(waitpid(pid[i], &status, 0) == pid[i]); 117 assert(status == 0); 118 } 119 } 120 121 static int load_progs(char *filename) 122 { 123 struct bpf_program *prog; 124 int err = 0; 125 126 obj = bpf_object__open_file(filename, NULL); 127 err = libbpf_get_error(obj); 128 if (err < 0) { 129 fprintf(stderr, "ERROR: opening BPF object file failed\n"); 130 return err; 131 } 132 133 /* load BPF program */ 134 err = bpf_object__load(obj); 135 if (err < 0) { 136 fprintf(stderr, "ERROR: loading BPF object file failed\n"); 137 return err; 138 } 139 140 bpf_object__for_each_program(prog, obj) { 141 links[cnt] = bpf_program__attach(prog); 142 err = libbpf_get_error(links[cnt]); 143 if (err < 0) { 144 fprintf(stderr, "ERROR: bpf_program__attach failed\n"); 145 links[cnt] = NULL; 146 return err; 147 } 148 cnt++; 149 } 150 151 return err; 152 } 153 154 static void unload_progs(void) 155 { 156 while (cnt) 157 bpf_link__destroy(links[--cnt]); 158 159 bpf_object__close(obj); 160 } 161 162 int main(int argc, char **argv) 163 { 164 int num_cpu = sysconf(_SC_NPROCESSORS_ONLN); 165 int test_flags = ~0; 166 char filename[256]; 167 int err = 0; 168 169 170 if (argc > 1) 171 test_flags = atoi(argv[1]) ? : test_flags; 172 if (argc > 2) 173 num_cpu = atoi(argv[2]) ? : num_cpu; 174 175 if (test_flags & 0x3) { 176 printf("BASE\n"); 177 run_perf_test(num_cpu, test_flags); 178 } 179 180 if (test_flags & 0xC) { 181 snprintf(filename, sizeof(filename), 182 "%s_kprobe_kern.o", argv[0]); 183 184 printf("w/KPROBE\n"); 185 err = load_progs(filename); 186 if (!err) 187 run_perf_test(num_cpu, test_flags >> 2); 188 189 unload_progs(); 190 } 191 192 if (test_flags & 0x30) { 193 snprintf(filename, sizeof(filename), 194 "%s_tp_kern.o", argv[0]); 195 printf("w/TRACEPOINT\n"); 196 err = load_progs(filename); 197 if (!err) 198 run_perf_test(num_cpu, test_flags >> 4); 199 200 unload_progs(); 201 } 202 203 if (test_flags & 0xC0) { 204 snprintf(filename, sizeof(filename), 205 "%s_raw_tp_kern.o", argv[0]); 206 printf("w/RAW_TRACEPOINT\n"); 207 err = load_progs(filename); 208 if (!err) 209 run_perf_test(num_cpu, test_flags >> 6); 210 211 unload_progs(); 212 } 213 214 return err; 215 } 216