1// SPDX-License-Identifier: GPL-2.0 2#include <errno.h> 3#include <stdio.h> 4#include <stdlib.h> 5#include <sys/epoll.h> 6#include <sys/types.h> 7#include <sys/stat.h> 8#include <fcntl.h> 9#include <util/record.h> 10#include <util/util.h> 11#include <util/bpf-loader.h> 12#include <util/evlist.h> 13#include <linux/bpf.h> 14#include <linux/filter.h> 15#include <linux/kernel.h> 16#include <linux/string.h> 17#include <api/fs/fs.h> 18#include <bpf/bpf.h> 19#include <perf/mmap.h> 20#include "tests.h" 21#include "llvm.h" 22#include "debug.h" 23#include "parse-events.h" 24#include "util/mmap.h" 25#define NR_ITERS 111 26#define PERF_TEST_BPF_PATH "/sys/fs/bpf/perf_test" 27 28#ifdef HAVE_LIBBPF_SUPPORT 29 30static int epoll_pwait_loop(void) 31{ 32 int i; 33 34 /* Should fail NR_ITERS times */ 35 for (i = 0; i < NR_ITERS; i++) 36 epoll_pwait(-(i + 1), NULL, 0, 0, NULL); 37 return 0; 38} 39 40#ifdef HAVE_BPF_PROLOGUE 41 42static int llseek_loop(void) 43{ 44 int fds[2], i; 45 46 fds[0] = open("/dev/null", O_RDONLY); 47 fds[1] = open("/dev/null", O_RDWR); 48 49 if (fds[0] < 0 || fds[1] < 0) 50 return -1; 51 52 for (i = 0; i < NR_ITERS; i++) { 53 lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); 54 lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); 55 } 56 close(fds[0]); 57 close(fds[1]); 58 return 0; 59} 60 61#endif 62 63static struct { 64 enum test_llvm__testcase prog_id; 65 const char *desc; 66 const char *name; 67 const char *msg_compile_fail; 68 const char *msg_load_fail; 69 int (*target_func)(void); 70 int expect_result; 71 bool pin; 72} bpf_testcase_table[] = { 73 { 74 .prog_id = LLVM_TESTCASE_BASE, 75 .desc = "Basic BPF filtering", 76 .name = "[basic_bpf_test]", 77 .msg_compile_fail = "fix 'perf test LLVM' first", 78 .msg_load_fail = "load bpf object failed", 79 .target_func = &epoll_pwait_loop, 80 .expect_result = (NR_ITERS + 1) / 2, 81 }, 82 { 83 .prog_id = LLVM_TESTCASE_BASE, 84 .desc = "BPF pinning", 85 .name = "[bpf_pinning]", 86 .msg_compile_fail = "fix kbuild first", 87 .msg_load_fail = "check your vmlinux setting?", 88 .target_func = &epoll_pwait_loop, 89 .expect_result = (NR_ITERS + 1) / 2, 90 .pin = true, 91 }, 92#ifdef HAVE_BPF_PROLOGUE 93 { 94 .prog_id = LLVM_TESTCASE_BPF_PROLOGUE, 95 .desc = "BPF prologue generation", 96 .name = "[bpf_prologue_test]", 97 .msg_compile_fail = "fix kbuild first", 98 .msg_load_fail = "check your vmlinux setting?", 99 .target_func = &llseek_loop, 100 .expect_result = (NR_ITERS + 1) / 4, 101 }, 102#endif 103 { 104 .prog_id = LLVM_TESTCASE_BPF_RELOCATION, 105 .desc = "BPF relocation checker", 106 .name = "[bpf_relocation_test]", 107 .msg_compile_fail = "fix 'perf test LLVM' first", 108 .msg_load_fail = "libbpf error when dealing with relocation", 109 }, 110}; 111 112static int do_test(struct bpf_object *obj, int (*func)(void), 113 int expect) 114{ 115 struct record_opts opts = { 116 .target = { 117 .uid = UINT_MAX, 118 .uses_mmap = true, 119 }, 120 .freq = 0, 121 .mmap_pages = 256, 122 .default_interval = 1, 123 }; 124 125 char pid[16]; 126 char sbuf[STRERR_BUFSIZE]; 127 struct evlist *evlist; 128 int i, ret = TEST_FAIL, err = 0, count = 0; 129 130 struct parse_events_state parse_state; 131 struct parse_events_error parse_error; 132 133 bzero(&parse_error, sizeof(parse_error)); 134 bzero(&parse_state, sizeof(parse_state)); 135 parse_state.error = &parse_error; 136 INIT_LIST_HEAD(&parse_state.list); 137 138 err = parse_events_load_bpf_obj(&parse_state, &parse_state.list, obj, NULL); 139 if (err || list_empty(&parse_state.list)) { 140 pr_debug("Failed to add events selected by BPF\n"); 141 return TEST_FAIL; 142 } 143 144 snprintf(pid, sizeof(pid), "%d", getpid()); 145 pid[sizeof(pid) - 1] = '\0'; 146 opts.target.tid = opts.target.pid = pid; 147 148 /* Instead of perf_evlist__new_default, don't add default events */ 149 evlist = evlist__new(); 150 if (!evlist) { 151 pr_debug("Not enough memory to create evlist\n"); 152 return TEST_FAIL; 153 } 154 155 err = perf_evlist__create_maps(evlist, &opts.target); 156 if (err < 0) { 157 pr_debug("Not enough memory to create thread/cpu maps\n"); 158 goto out_delete_evlist; 159 } 160 161 perf_evlist__splice_list_tail(evlist, &parse_state.list); 162 evlist->nr_groups = parse_state.nr_groups; 163 164 perf_evlist__config(evlist, &opts, NULL); 165 166 err = evlist__open(evlist); 167 if (err < 0) { 168 pr_debug("perf_evlist__open: %s\n", 169 str_error_r(errno, sbuf, sizeof(sbuf))); 170 goto out_delete_evlist; 171 } 172 173 err = evlist__mmap(evlist, opts.mmap_pages); 174 if (err < 0) { 175 pr_debug("evlist__mmap: %s\n", 176 str_error_r(errno, sbuf, sizeof(sbuf))); 177 goto out_delete_evlist; 178 } 179 180 evlist__enable(evlist); 181 (*func)(); 182 evlist__disable(evlist); 183 184 for (i = 0; i < evlist->core.nr_mmaps; i++) { 185 union perf_event *event; 186 struct mmap *md; 187 188 md = &evlist->mmap[i]; 189 if (perf_mmap__read_init(&md->core) < 0) 190 continue; 191 192 while ((event = perf_mmap__read_event(&md->core)) != NULL) { 193 const u32 type = event->header.type; 194 195 if (type == PERF_RECORD_SAMPLE) 196 count ++; 197 } 198 perf_mmap__read_done(&md->core); 199 } 200 201 if (count != expect * evlist->core.nr_entries) { 202 pr_debug("BPF filter result incorrect, expected %d, got %d samples\n", expect * evlist->core.nr_entries, count); 203 goto out_delete_evlist; 204 } 205 206 ret = TEST_OK; 207 208out_delete_evlist: 209 evlist__delete(evlist); 210 return ret; 211} 212 213static struct bpf_object * 214prepare_bpf(void *obj_buf, size_t obj_buf_sz, const char *name) 215{ 216 struct bpf_object *obj; 217 218 obj = bpf__prepare_load_buffer(obj_buf, obj_buf_sz, name); 219 if (IS_ERR(obj)) { 220 pr_debug("Compile BPF program failed.\n"); 221 return NULL; 222 } 223 return obj; 224} 225 226static int __test__bpf(int idx) 227{ 228 int ret; 229 void *obj_buf; 230 size_t obj_buf_sz; 231 struct bpf_object *obj; 232 233 ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz, 234 bpf_testcase_table[idx].prog_id, 235 true, NULL); 236 if (ret != TEST_OK || !obj_buf || !obj_buf_sz) { 237 pr_debug("Unable to get BPF object, %s\n", 238 bpf_testcase_table[idx].msg_compile_fail); 239 if (idx == 0) 240 return TEST_SKIP; 241 else 242 return TEST_FAIL; 243 } 244 245 obj = prepare_bpf(obj_buf, obj_buf_sz, 246 bpf_testcase_table[idx].name); 247 if ((!!bpf_testcase_table[idx].target_func) != (!!obj)) { 248 if (!obj) 249 pr_debug("Fail to load BPF object: %s\n", 250 bpf_testcase_table[idx].msg_load_fail); 251 else 252 pr_debug("Success unexpectedly: %s\n", 253 bpf_testcase_table[idx].msg_load_fail); 254 ret = TEST_FAIL; 255 goto out; 256 } 257 258 if (obj) { 259 ret = do_test(obj, 260 bpf_testcase_table[idx].target_func, 261 bpf_testcase_table[idx].expect_result); 262 if (ret != TEST_OK) 263 goto out; 264 if (bpf_testcase_table[idx].pin) { 265 int err; 266 267 if (!bpf_fs__mount()) { 268 pr_debug("BPF filesystem not mounted\n"); 269 ret = TEST_FAIL; 270 goto out; 271 } 272 err = mkdir(PERF_TEST_BPF_PATH, 0777); 273 if (err && errno != EEXIST) { 274 pr_debug("Failed to make perf_test dir: %s\n", 275 strerror(errno)); 276 ret = TEST_FAIL; 277 goto out; 278 } 279 if (bpf_object__pin(obj, PERF_TEST_BPF_PATH)) 280 ret = TEST_FAIL; 281 if (rm_rf(PERF_TEST_BPF_PATH)) 282 ret = TEST_FAIL; 283 } 284 } 285 286out: 287 free(obj_buf); 288 bpf__clear(); 289 return ret; 290} 291 292int test__bpf_subtest_get_nr(void) 293{ 294 return (int)ARRAY_SIZE(bpf_testcase_table); 295} 296 297const char *test__bpf_subtest_get_desc(int i) 298{ 299 if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table)) 300 return NULL; 301 return bpf_testcase_table[i].desc; 302} 303 304static int check_env(void) 305{ 306 int err; 307 unsigned int kver_int; 308 char license[] = "GPL"; 309 310 struct bpf_insn insns[] = { 311 BPF_MOV64_IMM(BPF_REG_0, 1), 312 BPF_EXIT_INSN(), 313 }; 314 315 err = fetch_kernel_version(&kver_int, NULL, 0); 316 if (err) { 317 pr_debug("Unable to get kernel version\n"); 318 return err; 319 } 320 321 err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns, 322 sizeof(insns) / sizeof(insns[0]), 323 license, kver_int, NULL, 0); 324 if (err < 0) { 325 pr_err("Missing basic BPF support, skip this test: %s\n", 326 strerror(errno)); 327 return err; 328 } 329 close(err); 330 331 return 0; 332} 333 334int test__bpf(struct test *test __maybe_unused, int i) 335{ 336 int err; 337 338 if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table)) 339 return TEST_FAIL; 340 341 if (geteuid() != 0) { 342 pr_debug("Only root can run BPF test\n"); 343 return TEST_SKIP; 344 } 345 346 if (check_env()) 347 return TEST_SKIP; 348 349 err = __test__bpf(i); 350 return err; 351} 352 353#else 354int test__bpf_subtest_get_nr(void) 355{ 356 return 0; 357} 358 359const char *test__bpf_subtest_get_desc(int i __maybe_unused) 360{ 361 return NULL; 362} 363 364int test__bpf(struct test *test __maybe_unused, int i __maybe_unused) 365{ 366 pr_debug("Skip BPF test because BPF support is not compiled\n"); 367 return TEST_SKIP; 368} 369#endif 370