1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * recordmcount.c: construct a table of the locations of calls to 'mcount'
4 * so that ftrace can find them quickly.
5 * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
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>
27 #include <getopt.h>
28 #include <elf.h>
29 #include <fcntl.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <unistd.h>
34
35 #ifndef EM_AARCH64
36 #define EM_AARCH64 183
37 #define R_AARCH64_NONE 0
38 #define R_AARCH64_ABS64 257
39 #endif
40
41 #define R_ARM_PC24 1
42 #define R_ARM_THM_CALL 10
43 #define R_ARM_CALL 28
44
45 #define R_AARCH64_CALL26 283
46
47 static int fd_map; /* File descriptor for file being modified. */
48 static int mmap_failed; /* Boolean flag. */
49 static char gpfx; /* prefix for global symbol name (sometimes '_') */
50 static struct stat sb; /* Remember .st_size, etc. */
51 static const char *altmcount; /* alternate mcount symbol name */
52 static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */
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
58 static void *file_append; /* added to the end of the file */
59 static size_t file_append_size; /* how much is added to end of file */
60
61 /* Per-file resource cleanup when multiple files. */
file_append_cleanup(void)62 static void file_append_cleanup(void)
63 {
64 free(file_append);
65 file_append = NULL;
66 file_append_size = 0;
67 file_updated = 0;
68 }
69
mmap_cleanup(void)70 static void mmap_cleanup(void)
71 {
72 if (!mmap_failed)
73 munmap(file_map, sb.st_size);
74 else
75 free(file_map);
76 file_map = NULL;
77 }
78
79 /* ulseek, uwrite, ...: Check return value for errors. */
80
ulseek(off_t const offset,int const whence)81 static off_t ulseek(off_t const offset, int const whence)
82 {
83 switch (whence) {
84 case SEEK_SET:
85 file_ptr = file_map + offset;
86 break;
87 case SEEK_CUR:
88 file_ptr += offset;
89 break;
90 case SEEK_END:
91 file_ptr = file_map + (sb.st_size - offset);
92 break;
93 }
94 if (file_ptr < file_map) {
95 fprintf(stderr, "lseek: seek before file\n");
96 return -1;
97 }
98 return file_ptr - file_map;
99 }
100
uwrite(void const * const buf,size_t const count)101 static ssize_t uwrite(void const *const buf, size_t const count)
102 {
103 size_t cnt = count;
104 off_t idx = 0;
105 void *p = NULL;
106
107 file_updated = 1;
108
109 if (file_ptr + count >= file_end) {
110 off_t aoffset = (file_ptr + count) - file_end;
111
112 if (aoffset > file_append_size) {
113 p = realloc(file_append, aoffset);
114 if (!p)
115 free(file_append);
116 file_append = p;
117 file_append_size = aoffset;
118 }
119 if (!file_append) {
120 perror("write");
121 file_append_cleanup();
122 mmap_cleanup();
123 return -1;
124 }
125 if (file_ptr < file_end) {
126 cnt = file_end - file_ptr;
127 } else {
128 cnt = 0;
129 idx = aoffset - count;
130 }
131 }
132
133 if (cnt)
134 memcpy(file_ptr, buf, cnt);
135
136 if (cnt < count)
137 memcpy(file_append + idx, buf + cnt, count - cnt);
138
139 file_ptr += count;
140 return count;
141 }
142
umalloc(size_t size)143 static void * umalloc(size_t size)
144 {
145 void *const addr = malloc(size);
146 if (addr == 0) {
147 fprintf(stderr, "malloc failed: %zu bytes\n", size);
148 file_append_cleanup();
149 mmap_cleanup();
150 return NULL;
151 }
152 return addr;
153 }
154
155 /*
156 * Get the whole file as a programming convenience in order to avoid
157 * malloc+lseek+read+free of many pieces. If successful, then mmap
158 * avoids copying unused pieces; else just read the whole file.
159 * Open for both read and write; new info will be appended to the file.
160 * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
161 * do not propagate to the file until an explicit overwrite at the last.
162 * This preserves most aspects of consistency (all except .st_size)
163 * for simultaneous readers of the file while we are appending to it.
164 * However, multiple writers still are bad. We choose not to use
165 * locking because it is expensive and the use case of kernel build
166 * makes multiple writers unlikely.
167 */
mmap_file(char const * fname)168 static void *mmap_file(char const *fname)
169 {
170 /* Avoid problems if early cleanup() */
171 fd_map = -1;
172 mmap_failed = 1;
173 file_map = NULL;
174 file_ptr = NULL;
175 file_updated = 0;
176 sb.st_size = 0;
177
178 fd_map = open(fname, O_RDONLY);
179 if (fd_map < 0) {
180 perror(fname);
181 return NULL;
182 }
183 if (fstat(fd_map, &sb) < 0) {
184 perror(fname);
185 goto out;
186 }
187 if (!S_ISREG(sb.st_mode)) {
188 fprintf(stderr, "not a regular file: %s\n", fname);
189 goto out;
190 }
191 file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
192 fd_map, 0);
193 if (file_map == MAP_FAILED) {
194 mmap_failed = 1;
195 file_map = umalloc(sb.st_size);
196 if (!file_map) {
197 perror(fname);
198 goto out;
199 }
200 if (read(fd_map, file_map, sb.st_size) != sb.st_size) {
201 perror(fname);
202 free(file_map);
203 file_map = NULL;
204 goto out;
205 }
206 } else
207 mmap_failed = 0;
208 out:
209 close(fd_map);
210 fd_map = -1;
211
212 file_end = file_map + sb.st_size;
213
214 return file_map;
215 }
216
217
218 static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
219 static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };
220 static unsigned char *ideal_nop;
221
222 static char rel_type_nop;
223
224 static int (*make_nop)(void *map, size_t const offset);
225
make_nop_x86(void * map,size_t const offset)226 static int make_nop_x86(void *map, size_t const offset)
227 {
228 uint32_t *ptr;
229 unsigned char *op;
230
231 /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */
232 ptr = map + offset;
233 if (*ptr != 0)
234 return -1;
235
236 op = map + offset - 1;
237 if (*op != 0xe8)
238 return -1;
239
240 /* convert to nop */
241 if (ulseek(offset - 1, SEEK_SET) < 0)
242 return -1;
243 if (uwrite(ideal_nop, 5) < 0)
244 return -1;
245 return 0;
246 }
247
248 static unsigned char ideal_nop4_arm_le[4] = { 0x00, 0x00, 0xa0, 0xe1 }; /* mov r0, r0 */
249 static unsigned char ideal_nop4_arm_be[4] = { 0xe1, 0xa0, 0x00, 0x00 }; /* mov r0, r0 */
250 static unsigned char *ideal_nop4_arm;
251
252 static unsigned char bl_mcount_arm_le[4] = { 0xfe, 0xff, 0xff, 0xeb }; /* bl */
253 static unsigned char bl_mcount_arm_be[4] = { 0xeb, 0xff, 0xff, 0xfe }; /* bl */
254 static unsigned char *bl_mcount_arm;
255
256 static unsigned char push_arm_le[4] = { 0x04, 0xe0, 0x2d, 0xe5 }; /* push {lr} */
257 static unsigned char push_arm_be[4] = { 0xe5, 0x2d, 0xe0, 0x04 }; /* push {lr} */
258 static unsigned char *push_arm;
259
260 static unsigned char ideal_nop2_thumb_le[2] = { 0x00, 0xbf }; /* nop */
261 static unsigned char ideal_nop2_thumb_be[2] = { 0xbf, 0x00 }; /* nop */
262 static unsigned char *ideal_nop2_thumb;
263
264 static unsigned char push_bl_mcount_thumb_le[6] = { 0x00, 0xb5, 0xff, 0xf7, 0xfe, 0xff }; /* push {lr}, bl */
265 static unsigned char push_bl_mcount_thumb_be[6] = { 0xb5, 0x00, 0xf7, 0xff, 0xff, 0xfe }; /* push {lr}, bl */
266 static unsigned char *push_bl_mcount_thumb;
267
make_nop_arm(void * map,size_t const offset)268 static int make_nop_arm(void *map, size_t const offset)
269 {
270 char *ptr;
271 int cnt = 1;
272 int nop_size;
273 size_t off = offset;
274
275 ptr = map + offset;
276 if (memcmp(ptr, bl_mcount_arm, 4) == 0) {
277 if (memcmp(ptr - 4, push_arm, 4) == 0) {
278 off -= 4;
279 cnt = 2;
280 }
281 ideal_nop = ideal_nop4_arm;
282 nop_size = 4;
283 } else if (memcmp(ptr - 2, push_bl_mcount_thumb, 6) == 0) {
284 cnt = 3;
285 nop_size = 2;
286 off -= 2;
287 ideal_nop = ideal_nop2_thumb;
288 } else
289 return -1;
290
291 /* Convert to nop */
292 if (ulseek(off, SEEK_SET) < 0)
293 return -1;
294
295 do {
296 if (uwrite(ideal_nop, nop_size) < 0)
297 return -1;
298 } while (--cnt > 0);
299
300 return 0;
301 }
302
303 static unsigned char ideal_nop4_arm64[4] = {0x1f, 0x20, 0x03, 0xd5};
make_nop_arm64(void * map,size_t const offset)304 static int make_nop_arm64(void *map, size_t const offset)
305 {
306 uint32_t *ptr;
307
308 ptr = map + offset;
309 /* bl <_mcount> is 0x94000000 before relocation */
310 if (*ptr != 0x94000000)
311 return -1;
312
313 /* Convert to nop */
314 if (ulseek(offset, SEEK_SET) < 0)
315 return -1;
316 if (uwrite(ideal_nop, 4) < 0)
317 return -1;
318 return 0;
319 }
320
write_file(const char * fname)321 static int write_file(const char *fname)
322 {
323 char tmp_file[strlen(fname) + 4];
324 size_t n;
325
326 if (!file_updated)
327 return 0;
328
329 sprintf(tmp_file, "%s.rc", fname);
330
331 /*
332 * After reading the entire file into memory, delete it
333 * and write it back, to prevent weird side effects of modifying
334 * an object file in place.
335 */
336 fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode);
337 if (fd_map < 0) {
338 perror(fname);
339 return -1;
340 }
341 n = write(fd_map, file_map, sb.st_size);
342 if (n != sb.st_size) {
343 perror("write");
344 close(fd_map);
345 return -1;
346 }
347 if (file_append_size) {
348 n = write(fd_map, file_append, file_append_size);
349 if (n != file_append_size) {
350 perror("write");
351 close(fd_map);
352 return -1;
353 }
354 }
355 close(fd_map);
356 if (rename(tmp_file, fname) < 0) {
357 perror(fname);
358 return -1;
359 }
360 return 0;
361 }
362
363 /* w8rev, w8nat, ...: Handle endianness. */
364
w8rev(uint64_t const x)365 static uint64_t w8rev(uint64_t const x)
366 {
367 return ((0xff & (x >> (0 * 8))) << (7 * 8))
368 | ((0xff & (x >> (1 * 8))) << (6 * 8))
369 | ((0xff & (x >> (2 * 8))) << (5 * 8))
370 | ((0xff & (x >> (3 * 8))) << (4 * 8))
371 | ((0xff & (x >> (4 * 8))) << (3 * 8))
372 | ((0xff & (x >> (5 * 8))) << (2 * 8))
373 | ((0xff & (x >> (6 * 8))) << (1 * 8))
374 | ((0xff & (x >> (7 * 8))) << (0 * 8));
375 }
376
w4rev(uint32_t const x)377 static uint32_t w4rev(uint32_t const x)
378 {
379 return ((0xff & (x >> (0 * 8))) << (3 * 8))
380 | ((0xff & (x >> (1 * 8))) << (2 * 8))
381 | ((0xff & (x >> (2 * 8))) << (1 * 8))
382 | ((0xff & (x >> (3 * 8))) << (0 * 8));
383 }
384
w2rev(uint16_t const x)385 static uint32_t w2rev(uint16_t const x)
386 {
387 return ((0xff & (x >> (0 * 8))) << (1 * 8))
388 | ((0xff & (x >> (1 * 8))) << (0 * 8));
389 }
390
w8nat(uint64_t const x)391 static uint64_t w8nat(uint64_t const x)
392 {
393 return x;
394 }
395
w4nat(uint32_t const x)396 static uint32_t w4nat(uint32_t const x)
397 {
398 return x;
399 }
400
w2nat(uint16_t const x)401 static uint32_t w2nat(uint16_t const x)
402 {
403 return x;
404 }
405
406 static uint64_t (*w8)(uint64_t);
407 static uint32_t (*w)(uint32_t);
408 static uint32_t (*w2)(uint16_t);
409
410 /* Names of the sections that could contain calls to mcount. */
is_mcounted_section_name(char const * const txtname)411 static int is_mcounted_section_name(char const *const txtname)
412 {
413 return strncmp(".text", txtname, 5) == 0 ||
414 strcmp(".init.text", txtname) == 0 ||
415 strcmp(".ref.text", txtname) == 0 ||
416 strcmp(".sched.text", txtname) == 0 ||
417 strcmp(".spinlock.text", txtname) == 0 ||
418 strcmp(".irqentry.text", txtname) == 0 ||
419 strcmp(".softirqentry.text", txtname) == 0 ||
420 strcmp(".kprobes.text", txtname) == 0 ||
421 strcmp(".cpuidle.text", txtname) == 0;
422 }
423
424 static char const *already_has_rel_mcount = "success"; /* our work here is done! */
425
426 /* 32 bit and 64 bit are very similar */
427 #include "recordmcount.h"
428 #define RECORD_MCOUNT_64
429 #include "recordmcount.h"
430
arm_is_fake_mcount(Elf32_Rel const * rp)431 static int arm_is_fake_mcount(Elf32_Rel const *rp)
432 {
433 switch (ELF32_R_TYPE(w(rp->r_info))) {
434 case R_ARM_THM_CALL:
435 case R_ARM_CALL:
436 case R_ARM_PC24:
437 return 0;
438 }
439
440 return 1;
441 }
442
arm64_is_fake_mcount(Elf64_Rel const * rp)443 static int arm64_is_fake_mcount(Elf64_Rel const *rp)
444 {
445 return ELF64_R_TYPE(w8(rp->r_info)) != R_AARCH64_CALL26;
446 }
447
448 /* 64-bit EM_MIPS has weird ELF64_Rela.r_info.
449 * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf
450 * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40]
451 * to imply the order of the members; the spec does not say so.
452 * typedef unsigned char Elf64_Byte;
453 * fails on MIPS64 because their <elf.h> already has it!
454 */
455
456 typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */
457
458 union mips_r_info {
459 Elf64_Xword r_info;
460 struct {
461 Elf64_Word r_sym; /* Symbol index. */
462 myElf64_Byte r_ssym; /* Special symbol. */
463 myElf64_Byte r_type3; /* Third relocation. */
464 myElf64_Byte r_type2; /* Second relocation. */
465 myElf64_Byte r_type; /* First relocation. */
466 } r_mips;
467 };
468
MIPS64_r_sym(Elf64_Rel const * rp)469 static uint64_t MIPS64_r_sym(Elf64_Rel const *rp)
470 {
471 return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym);
472 }
473
MIPS64_r_info(Elf64_Rel * const rp,unsigned sym,unsigned type)474 static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type)
475 {
476 rp->r_info = ((union mips_r_info){
477 .r_mips = { .r_sym = w(sym), .r_type = type }
478 }).r_info;
479 }
480
do_file(char const * const fname)481 static int do_file(char const *const fname)
482 {
483 unsigned int reltype = 0;
484 Elf32_Ehdr *ehdr;
485 int rc = -1;
486
487 ehdr = mmap_file(fname);
488 if (!ehdr)
489 goto out;
490
491 w = w4nat;
492 w2 = w2nat;
493 w8 = w8nat;
494 switch (ehdr->e_ident[EI_DATA]) {
495 static unsigned int const endian = 1;
496 default:
497 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
498 ehdr->e_ident[EI_DATA], fname);
499 goto out;
500 case ELFDATA2LSB:
501 if (*(unsigned char const *)&endian != 1) {
502 /* main() is big endian, file.o is little endian. */
503 w = w4rev;
504 w2 = w2rev;
505 w8 = w8rev;
506 }
507 ideal_nop4_arm = ideal_nop4_arm_le;
508 bl_mcount_arm = bl_mcount_arm_le;
509 push_arm = push_arm_le;
510 ideal_nop2_thumb = ideal_nop2_thumb_le;
511 push_bl_mcount_thumb = push_bl_mcount_thumb_le;
512 break;
513 case ELFDATA2MSB:
514 if (*(unsigned char const *)&endian != 0) {
515 /* main() is little endian, file.o is big endian. */
516 w = w4rev;
517 w2 = w2rev;
518 w8 = w8rev;
519 }
520 ideal_nop4_arm = ideal_nop4_arm_be;
521 bl_mcount_arm = bl_mcount_arm_be;
522 push_arm = push_arm_be;
523 ideal_nop2_thumb = ideal_nop2_thumb_be;
524 push_bl_mcount_thumb = push_bl_mcount_thumb_be;
525 break;
526 } /* end switch */
527 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 ||
528 w2(ehdr->e_type) != ET_REL ||
529 ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
530 fprintf(stderr, "unrecognized ET_REL file %s\n", fname);
531 goto out;
532 }
533
534 gpfx = '_';
535 switch (w2(ehdr->e_machine)) {
536 default:
537 fprintf(stderr, "unrecognized e_machine %u %s\n",
538 w2(ehdr->e_machine), fname);
539 goto out;
540 case EM_386:
541 reltype = R_386_32;
542 rel_type_nop = R_386_NONE;
543 make_nop = make_nop_x86;
544 ideal_nop = ideal_nop5_x86_32;
545 mcount_adjust_32 = -1;
546 gpfx = 0;
547 break;
548 case EM_ARM:
549 reltype = R_ARM_ABS32;
550 altmcount = "__gnu_mcount_nc";
551 make_nop = make_nop_arm;
552 rel_type_nop = R_ARM_NONE;
553 is_fake_mcount32 = arm_is_fake_mcount;
554 gpfx = 0;
555 break;
556 case EM_AARCH64:
557 reltype = R_AARCH64_ABS64;
558 make_nop = make_nop_arm64;
559 rel_type_nop = R_AARCH64_NONE;
560 ideal_nop = ideal_nop4_arm64;
561 is_fake_mcount64 = arm64_is_fake_mcount;
562 break;
563 case EM_IA_64: reltype = R_IA64_IMM64; break;
564 case EM_MIPS: /* reltype: e_class */ break;
565 case EM_PPC: reltype = R_PPC_ADDR32; break;
566 case EM_PPC64: reltype = R_PPC64_ADDR64; break;
567 case EM_S390: /* reltype: e_class */ break;
568 case EM_SH: reltype = R_SH_DIR32; gpfx = 0; break;
569 case EM_SPARCV9: reltype = R_SPARC_64; break;
570 case EM_X86_64:
571 make_nop = make_nop_x86;
572 ideal_nop = ideal_nop5_x86_64;
573 reltype = R_X86_64_64;
574 rel_type_nop = R_X86_64_NONE;
575 mcount_adjust_64 = -1;
576 gpfx = 0;
577 break;
578 } /* end switch */
579
580 switch (ehdr->e_ident[EI_CLASS]) {
581 default:
582 fprintf(stderr, "unrecognized ELF class %d %s\n",
583 ehdr->e_ident[EI_CLASS], fname);
584 goto out;
585 case ELFCLASS32:
586 if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
587 || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
588 fprintf(stderr,
589 "unrecognized ET_REL file: %s\n", fname);
590 goto out;
591 }
592 if (w2(ehdr->e_machine) == EM_MIPS) {
593 reltype = R_MIPS_32;
594 is_fake_mcount32 = MIPS32_is_fake_mcount;
595 }
596 if (do32(ehdr, fname, reltype) < 0)
597 goto out;
598 break;
599 case ELFCLASS64: {
600 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
601 if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
602 || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
603 fprintf(stderr,
604 "unrecognized ET_REL file: %s\n", fname);
605 goto out;
606 }
607 if (w2(ghdr->e_machine) == EM_S390) {
608 reltype = R_390_64;
609 mcount_adjust_64 = -14;
610 }
611 if (w2(ghdr->e_machine) == EM_MIPS) {
612 reltype = R_MIPS_64;
613 Elf64_r_sym = MIPS64_r_sym;
614 Elf64_r_info = MIPS64_r_info;
615 is_fake_mcount64 = MIPS64_is_fake_mcount;
616 }
617 if (do64(ghdr, fname, reltype) < 0)
618 goto out;
619 break;
620 }
621 } /* end switch */
622
623 rc = write_file(fname);
624 out:
625 file_append_cleanup();
626 mmap_cleanup();
627 return rc;
628 }
629
main(int argc,char * argv[])630 int main(int argc, char *argv[])
631 {
632 const char ftrace[] = "/ftrace.o";
633 int ftrace_size = sizeof(ftrace) - 1;
634 int n_error = 0; /* gcc-4.3.0 false positive complaint */
635 int c;
636 int i;
637
638 while ((c = getopt(argc, argv, "w")) >= 0) {
639 switch (c) {
640 case 'w':
641 warn_on_notrace_sect = 1;
642 break;
643 default:
644 fprintf(stderr, "usage: recordmcount [-w] file.o...\n");
645 return 0;
646 }
647 }
648
649 if ((argc - optind) < 1) {
650 fprintf(stderr, "usage: recordmcount [-w] file.o...\n");
651 return 0;
652 }
653
654 /* Process each file in turn, allowing deep failure. */
655 for (i = optind; i < argc; i++) {
656 char *file = argv[i];
657 int len;
658
659 /*
660 * The file kernel/trace/ftrace.o references the mcount
661 * function but does not call it. Since ftrace.o should
662 * not be traced anyway, we just skip it.
663 */
664 len = strlen(file);
665 if (len >= ftrace_size &&
666 strcmp(file + (len - ftrace_size), ftrace) == 0)
667 continue;
668
669 if (do_file(file)) {
670 fprintf(stderr, "%s: failed\n", file);
671 ++n_error;
672 }
673 }
674 return !!n_error;
675 }
676