John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 1 | /* |
| 2 | * recordmcount.c: construct a table of the locations of calls to 'mcount' |
| 3 | * so that ftrace can find them quickly. |
| 4 | * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. |
| 5 | * Licensed under the GNU General Public License, version 2 (GPLv2). |
| 6 | * |
| 7 | * Restructured to fit Linux format, as well as other updates: |
| 8 | * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * Strategy: alter the .o file in-place. |
| 13 | * |
| 14 | * Append a new STRTAB that has the new section names, followed by a new array |
| 15 | * ElfXX_Shdr[] that has the new section headers, followed by the section |
| 16 | * contents for __mcount_loc and its relocations. The old shstrtab strings, |
| 17 | * and the old ElfXX_Shdr[] array, remain as "garbage" (commonly, a couple |
| 18 | * kilobytes.) Subsequent processing by /bin/ld (or the kernel module loader) |
| 19 | * will ignore the garbage regions, because they are not designated by the |
| 20 | * new .e_shoff nor the new ElfXX_Shdr[]. [In order to remove the garbage, |
| 21 | * then use "ld -r" to create a new file that omits the garbage.] |
| 22 | */ |
| 23 | |
| 24 | #include <sys/types.h> |
| 25 | #include <sys/mman.h> |
| 26 | #include <sys/stat.h> |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 27 | #include <getopt.h> |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 28 | #include <elf.h> |
| 29 | #include <fcntl.h> |
| 30 | #include <setjmp.h> |
| 31 | #include <stdio.h> |
| 32 | #include <stdlib.h> |
| 33 | #include <string.h> |
| 34 | #include <unistd.h> |
| 35 | |
AKASHI Takahiro | af64d2a | 2014-04-30 10:54:32 +0100 | [diff] [blame] | 36 | #ifndef EM_AARCH64 |
| 37 | #define EM_AARCH64 183 |
Li Bin | 2ee8a74 | 2015-10-30 16:31:04 +0800 | [diff] [blame] | 38 | #define R_AARCH64_NONE 0 |
AKASHI Takahiro | af64d2a | 2014-04-30 10:54:32 +0100 | [diff] [blame] | 39 | #define R_AARCH64_ABS64 257 |
| 40 | #endif |
| 41 | |
Alex Sverdlin | ddb2f19 | 2020-01-08 15:57:47 +0100 | [diff] [blame] | 42 | #define R_ARM_PC24 1 |
| 43 | #define R_ARM_THM_CALL 10 |
| 44 | #define R_ARM_CALL 28 |
| 45 | |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 46 | static int fd_map; /* File descriptor for file being modified. */ |
| 47 | static int mmap_failed; /* Boolean flag. */ |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 48 | static char gpfx; /* prefix for global symbol name (sometimes '_') */ |
| 49 | static struct stat sb; /* Remember .st_size, etc. */ |
| 50 | static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */ |
Rabin Vincent | ed60453 | 2010-11-30 17:36:48 +0100 | [diff] [blame] | 51 | static const char *altmcount; /* alternate mcount symbol name */ |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 52 | static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */ |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 53 | static void *file_map; /* pointer of the mapped file */ |
| 54 | static void *file_end; /* pointer to the end of the mapped file */ |
| 55 | static int file_updated; /* flag to state file was changed */ |
| 56 | static void *file_ptr; /* current file pointer location */ |
| 57 | static void *file_append; /* added to the end of the file */ |
| 58 | static size_t file_append_size; /* how much is added to end of file */ |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 59 | |
| 60 | /* setjmp() return values */ |
| 61 | enum { |
| 62 | SJ_SETJMP = 0, /* hardwired first return */ |
| 63 | SJ_FAIL, |
| 64 | SJ_SUCCEED |
| 65 | }; |
| 66 | |
| 67 | /* Per-file resource cleanup when multiple files. */ |
| 68 | static void |
| 69 | cleanup(void) |
| 70 | { |
| 71 | if (!mmap_failed) |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 72 | munmap(file_map, sb.st_size); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 73 | else |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 74 | free(file_map); |
| 75 | file_map = NULL; |
| 76 | free(file_append); |
| 77 | file_append = NULL; |
| 78 | file_append_size = 0; |
| 79 | file_updated = 0; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 80 | } |
| 81 | |
| 82 | static void __attribute__((noreturn)) |
| 83 | fail_file(void) |
| 84 | { |
| 85 | cleanup(); |
| 86 | longjmp(jmpenv, SJ_FAIL); |
| 87 | } |
| 88 | |
| 89 | static void __attribute__((noreturn)) |
| 90 | succeed_file(void) |
| 91 | { |
| 92 | cleanup(); |
| 93 | longjmp(jmpenv, SJ_SUCCEED); |
| 94 | } |
| 95 | |
| 96 | /* ulseek, uread, ...: Check return value for errors. */ |
| 97 | |
| 98 | static off_t |
| 99 | ulseek(int const fd, off_t const offset, int const whence) |
| 100 | { |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 101 | switch (whence) { |
| 102 | case SEEK_SET: |
| 103 | file_ptr = file_map + offset; |
| 104 | break; |
| 105 | case SEEK_CUR: |
| 106 | file_ptr += offset; |
| 107 | break; |
| 108 | case SEEK_END: |
| 109 | file_ptr = file_map + (sb.st_size - offset); |
| 110 | break; |
| 111 | } |
| 112 | if (file_ptr < file_map) { |
| 113 | fprintf(stderr, "lseek: seek before file\n"); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 114 | fail_file(); |
| 115 | } |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 116 | return file_ptr - file_map; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 117 | } |
| 118 | |
| 119 | static size_t |
| 120 | uread(int const fd, void *const buf, size_t const count) |
| 121 | { |
| 122 | size_t const n = read(fd, buf, count); |
| 123 | if (n != count) { |
| 124 | perror("read"); |
| 125 | fail_file(); |
| 126 | } |
| 127 | return n; |
| 128 | } |
| 129 | |
| 130 | static size_t |
| 131 | uwrite(int const fd, void const *const buf, size_t const count) |
| 132 | { |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 133 | size_t cnt = count; |
| 134 | off_t idx = 0; |
| 135 | |
| 136 | file_updated = 1; |
| 137 | |
| 138 | if (file_ptr + count >= file_end) { |
| 139 | off_t aoffset = (file_ptr + count) - file_end; |
| 140 | |
| 141 | if (aoffset > file_append_size) { |
| 142 | file_append = realloc(file_append, aoffset); |
| 143 | file_append_size = aoffset; |
| 144 | } |
| 145 | if (!file_append) { |
| 146 | perror("write"); |
| 147 | fail_file(); |
| 148 | } |
| 149 | if (file_ptr < file_end) { |
| 150 | cnt = file_end - file_ptr; |
| 151 | } else { |
| 152 | cnt = 0; |
| 153 | idx = aoffset - count; |
| 154 | } |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 155 | } |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 156 | |
| 157 | if (cnt) |
| 158 | memcpy(file_ptr, buf, cnt); |
| 159 | |
| 160 | if (cnt < count) |
| 161 | memcpy(file_append + idx, buf + cnt, count - cnt); |
| 162 | |
| 163 | file_ptr += count; |
| 164 | return count; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | static void * |
| 168 | umalloc(size_t size) |
| 169 | { |
| 170 | void *const addr = malloc(size); |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 171 | if (addr == 0) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 172 | fprintf(stderr, "malloc failed: %zu bytes\n", size); |
| 173 | fail_file(); |
| 174 | } |
| 175 | return addr; |
| 176 | } |
| 177 | |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 178 | static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 }; |
| 179 | static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 }; |
| 180 | static unsigned char *ideal_nop; |
| 181 | |
| 182 | static char rel_type_nop; |
| 183 | |
| 184 | static int (*make_nop)(void *map, size_t const offset); |
| 185 | |
| 186 | static int make_nop_x86(void *map, size_t const offset) |
| 187 | { |
| 188 | uint32_t *ptr; |
| 189 | unsigned char *op; |
| 190 | |
| 191 | /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */ |
| 192 | ptr = map + offset; |
| 193 | if (*ptr != 0) |
| 194 | return -1; |
| 195 | |
| 196 | op = map + offset - 1; |
| 197 | if (*op != 0xe8) |
| 198 | return -1; |
| 199 | |
| 200 | /* convert to nop */ |
| 201 | ulseek(fd_map, offset - 1, SEEK_SET); |
| 202 | uwrite(fd_map, ideal_nop, 5); |
| 203 | return 0; |
| 204 | } |
| 205 | |
Stephen Boyd | 9648dc1 | 2016-10-18 16:42:00 -0700 | [diff] [blame] | 206 | static unsigned char ideal_nop4_arm_le[4] = { 0x00, 0x00, 0xa0, 0xe1 }; /* mov r0, r0 */ |
| 207 | static unsigned char ideal_nop4_arm_be[4] = { 0xe1, 0xa0, 0x00, 0x00 }; /* mov r0, r0 */ |
| 208 | static unsigned char *ideal_nop4_arm; |
| 209 | |
| 210 | static unsigned char bl_mcount_arm_le[4] = { 0xfe, 0xff, 0xff, 0xeb }; /* bl */ |
| 211 | static unsigned char bl_mcount_arm_be[4] = { 0xeb, 0xff, 0xff, 0xfe }; /* bl */ |
| 212 | static unsigned char *bl_mcount_arm; |
| 213 | |
| 214 | static unsigned char push_arm_le[4] = { 0x04, 0xe0, 0x2d, 0xe5 }; /* push {lr} */ |
| 215 | static unsigned char push_arm_be[4] = { 0xe5, 0x2d, 0xe0, 0x04 }; /* push {lr} */ |
| 216 | static unsigned char *push_arm; |
| 217 | |
| 218 | static unsigned char ideal_nop2_thumb_le[2] = { 0x00, 0xbf }; /* nop */ |
| 219 | static unsigned char ideal_nop2_thumb_be[2] = { 0xbf, 0x00 }; /* nop */ |
| 220 | static unsigned char *ideal_nop2_thumb; |
| 221 | |
| 222 | static unsigned char push_bl_mcount_thumb_le[6] = { 0x00, 0xb5, 0xff, 0xf7, 0xfe, 0xff }; /* push {lr}, bl */ |
| 223 | static unsigned char push_bl_mcount_thumb_be[6] = { 0xb5, 0x00, 0xf7, 0xff, 0xff, 0xfe }; /* push {lr}, bl */ |
| 224 | static unsigned char *push_bl_mcount_thumb; |
| 225 | |
| 226 | static int make_nop_arm(void *map, size_t const offset) |
| 227 | { |
| 228 | char *ptr; |
| 229 | int cnt = 1; |
| 230 | int nop_size; |
| 231 | size_t off = offset; |
| 232 | |
| 233 | ptr = map + offset; |
| 234 | if (memcmp(ptr, bl_mcount_arm, 4) == 0) { |
| 235 | if (memcmp(ptr - 4, push_arm, 4) == 0) { |
| 236 | off -= 4; |
| 237 | cnt = 2; |
| 238 | } |
| 239 | ideal_nop = ideal_nop4_arm; |
| 240 | nop_size = 4; |
| 241 | } else if (memcmp(ptr - 2, push_bl_mcount_thumb, 6) == 0) { |
| 242 | cnt = 3; |
| 243 | nop_size = 2; |
| 244 | off -= 2; |
| 245 | ideal_nop = ideal_nop2_thumb; |
| 246 | } else |
| 247 | return -1; |
| 248 | |
| 249 | /* Convert to nop */ |
| 250 | ulseek(fd_map, off, SEEK_SET); |
| 251 | |
| 252 | do { |
| 253 | uwrite(fd_map, ideal_nop, nop_size); |
| 254 | } while (--cnt > 0); |
| 255 | |
| 256 | return 0; |
| 257 | } |
| 258 | |
Li Bin | 2ee8a74 | 2015-10-30 16:31:04 +0800 | [diff] [blame] | 259 | static unsigned char ideal_nop4_arm64[4] = {0x1f, 0x20, 0x03, 0xd5}; |
| 260 | static int make_nop_arm64(void *map, size_t const offset) |
| 261 | { |
| 262 | uint32_t *ptr; |
| 263 | |
| 264 | ptr = map + offset; |
| 265 | /* bl <_mcount> is 0x94000000 before relocation */ |
| 266 | if (*ptr != 0x94000000) |
| 267 | return -1; |
| 268 | |
| 269 | /* Convert to nop */ |
| 270 | ulseek(fd_map, offset, SEEK_SET); |
| 271 | uwrite(fd_map, ideal_nop, 4); |
| 272 | return 0; |
| 273 | } |
| 274 | |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 275 | /* |
| 276 | * Get the whole file as a programming convenience in order to avoid |
| 277 | * malloc+lseek+read+free of many pieces. If successful, then mmap |
| 278 | * avoids copying unused pieces; else just read the whole file. |
| 279 | * Open for both read and write; new info will be appended to the file. |
| 280 | * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr |
| 281 | * do not propagate to the file until an explicit overwrite at the last. |
| 282 | * This preserves most aspects of consistency (all except .st_size) |
| 283 | * for simultaneous readers of the file while we are appending to it. |
| 284 | * However, multiple writers still are bad. We choose not to use |
| 285 | * locking because it is expensive and the use case of kernel build |
| 286 | * makes multiple writers unlikely. |
| 287 | */ |
| 288 | static void *mmap_file(char const *fname) |
| 289 | { |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 290 | fd_map = open(fname, O_RDONLY); |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 291 | if (fd_map < 0 || fstat(fd_map, &sb) < 0) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 292 | perror(fname); |
| 293 | fail_file(); |
| 294 | } |
| 295 | if (!S_ISREG(sb.st_mode)) { |
| 296 | fprintf(stderr, "not a regular file: %s\n", fname); |
| 297 | fail_file(); |
| 298 | } |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 299 | file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, |
| 300 | fd_map, 0); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 301 | mmap_failed = 0; |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 302 | if (file_map == MAP_FAILED) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 303 | mmap_failed = 1; |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 304 | file_map = umalloc(sb.st_size); |
| 305 | uread(fd_map, file_map, sb.st_size); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 306 | } |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 307 | close(fd_map); |
| 308 | |
| 309 | file_end = file_map + sb.st_size; |
| 310 | |
| 311 | return file_map; |
| 312 | } |
| 313 | |
| 314 | static void write_file(const char *fname) |
| 315 | { |
| 316 | char tmp_file[strlen(fname) + 4]; |
| 317 | size_t n; |
| 318 | |
| 319 | if (!file_updated) |
| 320 | return; |
| 321 | |
| 322 | sprintf(tmp_file, "%s.rc", fname); |
| 323 | |
| 324 | /* |
| 325 | * After reading the entire file into memory, delete it |
| 326 | * and write it back, to prevent weird side effects of modifying |
| 327 | * an object file in place. |
| 328 | */ |
| 329 | fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode); |
| 330 | if (fd_map < 0) { |
| 331 | perror(fname); |
| 332 | fail_file(); |
| 333 | } |
| 334 | n = write(fd_map, file_map, sb.st_size); |
| 335 | if (n != sb.st_size) { |
| 336 | perror("write"); |
| 337 | fail_file(); |
| 338 | } |
| 339 | if (file_append_size) { |
| 340 | n = write(fd_map, file_append, file_append_size); |
| 341 | if (n != file_append_size) { |
| 342 | perror("write"); |
Russell King | dd39a26 | 2015-12-11 12:09:03 +0000 | [diff] [blame] | 343 | fail_file(); |
| 344 | } |
Russell King | dd39a26 | 2015-12-11 12:09:03 +0000 | [diff] [blame] | 345 | } |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 346 | close(fd_map); |
| 347 | if (rename(tmp_file, fname) < 0) { |
| 348 | perror(fname); |
| 349 | fail_file(); |
| 350 | } |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 351 | } |
| 352 | |
| 353 | /* w8rev, w8nat, ...: Handle endianness. */ |
| 354 | |
| 355 | static uint64_t w8rev(uint64_t const x) |
| 356 | { |
| 357 | return ((0xff & (x >> (0 * 8))) << (7 * 8)) |
| 358 | | ((0xff & (x >> (1 * 8))) << (6 * 8)) |
| 359 | | ((0xff & (x >> (2 * 8))) << (5 * 8)) |
| 360 | | ((0xff & (x >> (3 * 8))) << (4 * 8)) |
| 361 | | ((0xff & (x >> (4 * 8))) << (3 * 8)) |
| 362 | | ((0xff & (x >> (5 * 8))) << (2 * 8)) |
| 363 | | ((0xff & (x >> (6 * 8))) << (1 * 8)) |
| 364 | | ((0xff & (x >> (7 * 8))) << (0 * 8)); |
| 365 | } |
| 366 | |
| 367 | static uint32_t w4rev(uint32_t const x) |
| 368 | { |
| 369 | return ((0xff & (x >> (0 * 8))) << (3 * 8)) |
| 370 | | ((0xff & (x >> (1 * 8))) << (2 * 8)) |
| 371 | | ((0xff & (x >> (2 * 8))) << (1 * 8)) |
| 372 | | ((0xff & (x >> (3 * 8))) << (0 * 8)); |
| 373 | } |
| 374 | |
| 375 | static uint32_t w2rev(uint16_t const x) |
| 376 | { |
| 377 | return ((0xff & (x >> (0 * 8))) << (1 * 8)) |
| 378 | | ((0xff & (x >> (1 * 8))) << (0 * 8)); |
| 379 | } |
| 380 | |
| 381 | static uint64_t w8nat(uint64_t const x) |
| 382 | { |
| 383 | return x; |
| 384 | } |
| 385 | |
| 386 | static uint32_t w4nat(uint32_t const x) |
| 387 | { |
| 388 | return x; |
| 389 | } |
| 390 | |
| 391 | static uint32_t w2nat(uint16_t const x) |
| 392 | { |
| 393 | return x; |
| 394 | } |
| 395 | |
| 396 | static uint64_t (*w8)(uint64_t); |
| 397 | static uint32_t (*w)(uint32_t); |
| 398 | static uint32_t (*w2)(uint16_t); |
| 399 | |
| 400 | /* Names of the sections that could contain calls to mcount. */ |
| 401 | static int |
| 402 | is_mcounted_section_name(char const *const txtname) |
| 403 | { |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 404 | return strcmp(".text", txtname) == 0 || |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 405 | strcmp(".init.text", txtname) == 0 || |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 406 | strcmp(".ref.text", txtname) == 0 || |
| 407 | strcmp(".sched.text", txtname) == 0 || |
| 408 | strcmp(".spinlock.text", txtname) == 0 || |
| 409 | strcmp(".irqentry.text", txtname) == 0 || |
Dmitry Vyukov | e436fd6 | 2016-09-28 15:22:36 -0700 | [diff] [blame] | 410 | strcmp(".softirqentry.text", txtname) == 0 || |
Steven Rostedt | 9f087e7 | 2011-04-06 14:10:22 -0400 | [diff] [blame] | 411 | strcmp(".kprobes.text", txtname) == 0 || |
Chris Metcalf | 6727ad9 | 2016-10-07 17:02:55 -0700 | [diff] [blame] | 412 | strcmp(".cpuidle.text", txtname) == 0 || |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 413 | strcmp(".text.unlikely", txtname) == 0; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 414 | } |
| 415 | |
Steven Rostedt | c28d507 | 2010-10-13 19:06:14 -0400 | [diff] [blame] | 416 | /* 32 bit and 64 bit are very similar */ |
| 417 | #include "recordmcount.h" |
| 418 | #define RECORD_MCOUNT_64 |
| 419 | #include "recordmcount.h" |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 420 | |
Alex Sverdlin | ddb2f19 | 2020-01-08 15:57:47 +0100 | [diff] [blame] | 421 | static int arm_is_fake_mcount(Elf32_Rel const *rp) |
| 422 | { |
| 423 | switch (ELF32_R_TYPE(w(rp->r_info))) { |
| 424 | case R_ARM_THM_CALL: |
| 425 | case R_ARM_CALL: |
| 426 | case R_ARM_PC24: |
| 427 | return 0; |
| 428 | } |
| 429 | |
| 430 | return 1; |
| 431 | } |
| 432 | |
John Reiser | a2d49358 | 2010-10-27 18:59:07 +0800 | [diff] [blame] | 433 | /* 64-bit EM_MIPS has weird ELF64_Rela.r_info. |
| 434 | * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf |
| 435 | * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40] |
| 436 | * to imply the order of the members; the spec does not say so. |
| 437 | * typedef unsigned char Elf64_Byte; |
| 438 | * fails on MIPS64 because their <elf.h> already has it! |
| 439 | */ |
| 440 | |
| 441 | typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */ |
| 442 | |
| 443 | union mips_r_info { |
| 444 | Elf64_Xword r_info; |
| 445 | struct { |
| 446 | Elf64_Word r_sym; /* Symbol index. */ |
| 447 | myElf64_Byte r_ssym; /* Special symbol. */ |
| 448 | myElf64_Byte r_type3; /* Third relocation. */ |
| 449 | myElf64_Byte r_type2; /* Second relocation. */ |
| 450 | myElf64_Byte r_type; /* First relocation. */ |
| 451 | } r_mips; |
| 452 | }; |
| 453 | |
| 454 | static uint64_t MIPS64_r_sym(Elf64_Rel const *rp) |
| 455 | { |
| 456 | return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym); |
| 457 | } |
| 458 | |
| 459 | static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type) |
| 460 | { |
| 461 | rp->r_info = ((union mips_r_info){ |
| 462 | .r_mips = { .r_sym = w(sym), .r_type = type } |
| 463 | }).r_info; |
| 464 | } |
| 465 | |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 466 | static void |
| 467 | do_file(char const *const fname) |
| 468 | { |
| 469 | Elf32_Ehdr *const ehdr = mmap_file(fname); |
| 470 | unsigned int reltype = 0; |
| 471 | |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 472 | w = w4nat; |
| 473 | w2 = w2nat; |
| 474 | w8 = w8nat; |
| 475 | switch (ehdr->e_ident[EI_DATA]) { |
| 476 | static unsigned int const endian = 1; |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 477 | default: |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 478 | fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", |
| 479 | ehdr->e_ident[EI_DATA], fname); |
| 480 | fail_file(); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 481 | break; |
| 482 | case ELFDATA2LSB: |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 483 | if (*(unsigned char const *)&endian != 1) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 484 | /* main() is big endian, file.o is little endian. */ |
| 485 | w = w4rev; |
| 486 | w2 = w2rev; |
| 487 | w8 = w8rev; |
| 488 | } |
Stephen Boyd | 9648dc1 | 2016-10-18 16:42:00 -0700 | [diff] [blame] | 489 | ideal_nop4_arm = ideal_nop4_arm_le; |
| 490 | bl_mcount_arm = bl_mcount_arm_le; |
| 491 | push_arm = push_arm_le; |
| 492 | ideal_nop2_thumb = ideal_nop2_thumb_le; |
| 493 | push_bl_mcount_thumb = push_bl_mcount_thumb_le; |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 494 | break; |
| 495 | case ELFDATA2MSB: |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 496 | if (*(unsigned char const *)&endian != 0) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 497 | /* main() is little endian, file.o is big endian. */ |
| 498 | w = w4rev; |
| 499 | w2 = w2rev; |
| 500 | w8 = w8rev; |
| 501 | } |
Stephen Boyd | 9648dc1 | 2016-10-18 16:42:00 -0700 | [diff] [blame] | 502 | ideal_nop4_arm = ideal_nop4_arm_be; |
| 503 | bl_mcount_arm = bl_mcount_arm_be; |
| 504 | push_arm = push_arm_be; |
| 505 | ideal_nop2_thumb = ideal_nop2_thumb_be; |
| 506 | push_bl_mcount_thumb = push_bl_mcount_thumb_be; |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 507 | break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 508 | } /* end switch */ |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 509 | if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 |
| 510 | || w2(ehdr->e_type) != ET_REL |
| 511 | || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 512 | fprintf(stderr, "unrecognized ET_REL file %s\n", fname); |
| 513 | fail_file(); |
| 514 | } |
| 515 | |
| 516 | gpfx = 0; |
| 517 | switch (w2(ehdr->e_machine)) { |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 518 | default: |
nixiaoming | ac5db1f | 2018-05-24 11:16:12 +0800 | [diff] [blame] | 519 | fprintf(stderr, "unrecognized e_machine %u %s\n", |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 520 | w2(ehdr->e_machine), fname); |
| 521 | fail_file(); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 522 | break; |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 523 | case EM_386: |
| 524 | reltype = R_386_32; |
Li Bin | 46a2b61 | 2015-10-28 16:23:26 +0800 | [diff] [blame] | 525 | rel_type_nop = R_386_NONE; |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 526 | make_nop = make_nop_x86; |
| 527 | ideal_nop = ideal_nop5_x86_32; |
Martin Schwidefsky | 521ccb5 | 2011-05-10 10:10:41 +0200 | [diff] [blame] | 528 | mcount_adjust_32 = -1; |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 529 | break; |
Rabin Vincent | ed60453 | 2010-11-30 17:36:48 +0100 | [diff] [blame] | 530 | case EM_ARM: reltype = R_ARM_ABS32; |
| 531 | altmcount = "__gnu_mcount_nc"; |
Stephen Boyd | 9648dc1 | 2016-10-18 16:42:00 -0700 | [diff] [blame] | 532 | make_nop = make_nop_arm; |
| 533 | rel_type_nop = R_ARM_NONE; |
Alex Sverdlin | ddb2f19 | 2020-01-08 15:57:47 +0100 | [diff] [blame] | 534 | is_fake_mcount32 = arm_is_fake_mcount; |
Rabin Vincent | ed60453 | 2010-11-30 17:36:48 +0100 | [diff] [blame] | 535 | break; |
AKASHI Takahiro | af64d2a | 2014-04-30 10:54:32 +0100 | [diff] [blame] | 536 | case EM_AARCH64: |
Li Bin | 2ee8a74 | 2015-10-30 16:31:04 +0800 | [diff] [blame] | 537 | reltype = R_AARCH64_ABS64; |
| 538 | make_nop = make_nop_arm64; |
| 539 | rel_type_nop = R_AARCH64_NONE; |
| 540 | ideal_nop = ideal_nop4_arm64; |
| 541 | gpfx = '_'; |
| 542 | break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 543 | case EM_IA_64: reltype = R_IA64_IMM64; gpfx = '_'; break; |
John Reiser | a2d49358 | 2010-10-27 18:59:07 +0800 | [diff] [blame] | 544 | case EM_MIPS: /* reltype: e_class */ gpfx = '_'; break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 545 | case EM_PPC: reltype = R_PPC_ADDR32; gpfx = '_'; break; |
| 546 | case EM_PPC64: reltype = R_PPC64_ADDR64; gpfx = '_'; break; |
| 547 | case EM_S390: /* reltype: e_class */ gpfx = '_'; break; |
| 548 | case EM_SH: reltype = R_SH_DIR32; break; |
| 549 | case EM_SPARCV9: reltype = R_SPARC_64; gpfx = '_'; break; |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 550 | case EM_X86_64: |
| 551 | make_nop = make_nop_x86; |
| 552 | ideal_nop = ideal_nop5_x86_64; |
| 553 | reltype = R_X86_64_64; |
Li Bin | 46a2b61 | 2015-10-28 16:23:26 +0800 | [diff] [blame] | 554 | rel_type_nop = R_X86_64_NONE; |
Martin Schwidefsky | 521ccb5 | 2011-05-10 10:10:41 +0200 | [diff] [blame] | 555 | mcount_adjust_64 = -1; |
Steven Rostedt | ffd618f | 2011-04-08 03:58:48 -0400 | [diff] [blame] | 556 | break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 557 | } /* end switch */ |
| 558 | |
| 559 | switch (ehdr->e_ident[EI_CLASS]) { |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 560 | default: |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 561 | fprintf(stderr, "unrecognized ELF class %d %s\n", |
| 562 | ehdr->e_ident[EI_CLASS], fname); |
| 563 | fail_file(); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 564 | break; |
| 565 | case ELFCLASS32: |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 566 | if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) |
| 567 | || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 568 | fprintf(stderr, |
| 569 | "unrecognized ET_REL file: %s\n", fname); |
| 570 | fail_file(); |
| 571 | } |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 572 | if (w2(ehdr->e_machine) == EM_MIPS) { |
John Reiser | a2d49358 | 2010-10-27 18:59:07 +0800 | [diff] [blame] | 573 | reltype = R_MIPS_32; |
Wu Zhangjin | 412910c | 2010-10-27 18:59:08 +0800 | [diff] [blame] | 574 | is_fake_mcount32 = MIPS32_is_fake_mcount; |
| 575 | } |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 576 | do32(ehdr, fname, reltype); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 577 | break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 578 | case ELFCLASS64: { |
| 579 | Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 580 | if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr) |
| 581 | || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 582 | fprintf(stderr, |
| 583 | "unrecognized ET_REL file: %s\n", fname); |
| 584 | fail_file(); |
| 585 | } |
Martin Schwidefsky | f296388 | 2011-05-10 10:10:43 +0200 | [diff] [blame] | 586 | if (w2(ghdr->e_machine) == EM_S390) { |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 587 | reltype = R_390_64; |
Heiko Carstens | c933146 | 2014-10-15 12:17:38 +0200 | [diff] [blame] | 588 | mcount_adjust_64 = -14; |
Martin Schwidefsky | f296388 | 2011-05-10 10:10:43 +0200 | [diff] [blame] | 589 | } |
Steven Rostedt | dd5477f | 2011-04-06 13:21:17 -0400 | [diff] [blame] | 590 | if (w2(ghdr->e_machine) == EM_MIPS) { |
John Reiser | a2d49358 | 2010-10-27 18:59:07 +0800 | [diff] [blame] | 591 | reltype = R_MIPS_64; |
| 592 | Elf64_r_sym = MIPS64_r_sym; |
| 593 | Elf64_r_info = MIPS64_r_info; |
Wu Zhangjin | 412910c | 2010-10-27 18:59:08 +0800 | [diff] [blame] | 594 | is_fake_mcount64 = MIPS64_is_fake_mcount; |
John Reiser | a2d49358 | 2010-10-27 18:59:07 +0800 | [diff] [blame] | 595 | } |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 596 | do64(ghdr, fname, reltype); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 597 | break; |
| 598 | } |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 599 | } /* end switch */ |
| 600 | |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 601 | write_file(fname); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 602 | cleanup(); |
| 603 | } |
| 604 | |
| 605 | int |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 606 | main(int argc, char *argv[]) |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 607 | { |
Rabin Vincent | cd3478f | 2010-11-30 17:33:53 +0100 | [diff] [blame] | 608 | const char ftrace[] = "/ftrace.o"; |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 609 | int ftrace_size = sizeof(ftrace) - 1; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 610 | int n_error = 0; /* gcc-4.3.0 false positive complaint */ |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 611 | int c; |
| 612 | int i; |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 613 | |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 614 | while ((c = getopt(argc, argv, "w")) >= 0) { |
| 615 | switch (c) { |
| 616 | case 'w': |
| 617 | warn_on_notrace_sect = 1; |
| 618 | break; |
| 619 | default: |
| 620 | fprintf(stderr, "usage: recordmcount [-w] file.o...\n"); |
| 621 | return 0; |
| 622 | } |
| 623 | } |
| 624 | |
| 625 | if ((argc - optind) < 1) { |
| 626 | fprintf(stderr, "usage: recordmcount [-w] file.o...\n"); |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 627 | return 0; |
| 628 | } |
| 629 | |
| 630 | /* Process each file in turn, allowing deep failure. */ |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 631 | for (i = optind; i < argc; i++) { |
| 632 | char *file = argv[i]; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 633 | int const sjval = setjmp(jmpenv); |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 634 | int len; |
| 635 | |
| 636 | /* |
| 637 | * The file kernel/trace/ftrace.o references the mcount |
| 638 | * function but does not call it. Since ftrace.o should |
| 639 | * not be traced anyway, we just skip it. |
| 640 | */ |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 641 | len = strlen(file); |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 642 | if (len >= ftrace_size && |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 643 | strcmp(file + (len - ftrace_size), ftrace) == 0) |
Steven Rostedt | 4447586 | 2010-10-15 11:49:47 -0400 | [diff] [blame] | 644 | continue; |
| 645 | |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 646 | switch (sjval) { |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 647 | default: |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 648 | fprintf(stderr, "internal error: %s\n", file); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 649 | exit(1); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 650 | break; |
| 651 | case SJ_SETJMP: /* normal sequence */ |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 652 | /* Avoid problems if early cleanup() */ |
| 653 | fd_map = -1; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 654 | mmap_failed = 1; |
Steven Rostedt (Red Hat) | a50bd43 | 2015-12-15 16:06:10 -0500 | [diff] [blame] | 655 | file_map = NULL; |
| 656 | file_ptr = NULL; |
| 657 | file_updated = 0; |
Steven Rostedt | dfad3d5 | 2011-04-12 18:53:25 -0400 | [diff] [blame] | 658 | do_file(file); |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 659 | break; |
| 660 | case SJ_FAIL: /* error in do_file or below */ |
Colin Ian King | 713a3e4 | 2015-12-30 23:06:41 +0000 | [diff] [blame] | 661 | fprintf(stderr, "%s: failed\n", file); |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 662 | ++n_error; |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 663 | break; |
| 664 | case SJ_SUCCEED: /* premature success */ |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 665 | /* do nothing */ |
Steven Rostedt | e90b0c8 | 2011-04-06 13:32:24 -0400 | [diff] [blame] | 666 | break; |
John Reiser | 81d3858 | 2010-10-13 15:12:54 -0400 | [diff] [blame] | 667 | } /* end switch */ |
| 668 | } |
| 669 | return !!n_error; |
| 670 | } |