scripts/recordmcount.h

   1 /*
   2  * recordmcount.h
   3  *
   4  * This code was taken out of recordmcount.c written by
   5  * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
   6  *
   7  * The original code had the same algorithms for both 32bit
   8  * and 64bit ELF files, but the code was duplicated to support
   9  * the difference in structures that were used. This
  10  * file creates a macro of everything that is different between
  11  * the 64 and 32 bit code, such that by including this header
  12  * twice we can create both sets of functions by including this
  13  * header once with RECORD_MCOUNT_64 undefined, and again with
  14  * it defined.
  15  *
  16  * This conversion to macros was done by:
  17  * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
  18  *
  19  * Licensed under the GNU General Public License, version 2 (GPLv2).
  20  */
  21 #undef append_func
  22 #undef is_fake_mcount
  23 #undef fn_is_fake_mcount
  24 #undef MIPS_is_fake_mcount
  25 #undef mcount_adjust
  26 #undef sift_rel_mcount
  27 #undef nop_mcount
  28 #undef find_secsym_ndx
  29 #undef __has_rel_mcount
  30 #undef has_rel_mcount
  31 #undef tot_relsize
  32 #undef get_mcountsym
  33 #undef get_sym_str_and_relp
  34 #undef do_func
  35 #undef Elf_Addr
  36 #undef Elf_Ehdr
  37 #undef Elf_Shdr
  38 #undef Elf_Rel
  39 #undef Elf_Rela
  40 #undef Elf_Sym
  41 #undef ELF_R_SYM
  42 #undef Elf_r_sym
  43 #undef ELF_R_INFO
  44 #undef Elf_r_info
  45 #undef ELF_ST_BIND
  46 #undef ELF_ST_TYPE
  47 #undef fn_ELF_R_SYM
  48 #undef fn_ELF_R_INFO
  49 #undef uint_t
  50 #undef _w
  51 #undef _align
  52 #undef _size
  53
  54 #ifdef RECORD_MCOUNT_64
  55 # define append_func            append64
  56 # define sift_rel_mcount        sift64_rel_mcount
  57 # define nop_mcount             nop_mcount_64
  58 # define find_secsym_ndx        find64_secsym_ndx
  59 # define __has_rel_mcount       __has64_rel_mcount
  60 # define has_rel_mcount         has64_rel_mcount
  61 # define tot_relsize            tot64_relsize
  62 # define get_sym_str_and_relp   get_sym_str_and_relp_64
  63 # define do_func                do64
  64 # define get_mcountsym          get_mcountsym_64
  65 # define is_fake_mcount         is_fake_mcount64
  66 # define fn_is_fake_mcount      fn_is_fake_mcount64
  67 # define MIPS_is_fake_mcount    MIPS64_is_fake_mcount
  68 # define mcount_adjust          mcount_adjust_64
  69 # define Elf_Addr               Elf64_Addr
  70 # define Elf_Ehdr               Elf64_Ehdr
  71 # define Elf_Shdr               Elf64_Shdr
  72 # define Elf_Rel                Elf64_Rel
  73 # define Elf_Rela               Elf64_Rela
  74 # define Elf_Sym                Elf64_Sym
  75 # define ELF_R_SYM              ELF64_R_SYM
  76 # define Elf_r_sym              Elf64_r_sym
  77 # define ELF_R_INFO             ELF64_R_INFO
  78 # define Elf_r_info             Elf64_r_info
  79 # define ELF_ST_BIND            ELF64_ST_BIND
  80 # define ELF_ST_TYPE            ELF64_ST_TYPE
  81 # define fn_ELF_R_SYM           fn_ELF64_R_SYM
  82 # define fn_ELF_R_INFO          fn_ELF64_R_INFO
  83 # define uint_t                 uint64_t
  84 # define _w                     w8
  85 # define _align                 7u
  86 # define _size                  8
  87 #else
  88 # define append_func            append32
  89 # define sift_rel_mcount        sift32_rel_mcount
  90 # define nop_mcount             nop_mcount_32
  91 # define find_secsym_ndx        find32_secsym_ndx
  92 # define __has_rel_mcount       __has32_rel_mcount
  93 # define has_rel_mcount         has32_rel_mcount
  94 # define tot_relsize            tot32_relsize
  95 # define get_sym_str_and_relp   get_sym_str_and_relp_32
  96 # define do_func                do32
  97 # define get_mcountsym          get_mcountsym_32
  98 # define is_fake_mcount         is_fake_mcount32
  99 # define fn_is_fake_mcount      fn_is_fake_mcount32
 100 # define MIPS_is_fake_mcount    MIPS32_is_fake_mcount
 101 # define mcount_adjust          mcount_adjust_32
 102 # define Elf_Addr               Elf32_Addr
 103 # define Elf_Ehdr               Elf32_Ehdr
 104 # define Elf_Shdr               Elf32_Shdr
 105 # define Elf_Rel                Elf32_Rel
 106 # define Elf_Rela               Elf32_Rela
 107 # define Elf_Sym                Elf32_Sym
 108 # define ELF_R_SYM              ELF32_R_SYM
 109 # define Elf_r_sym              Elf32_r_sym
 110 # define ELF_R_INFO             ELF32_R_INFO
 111 # define Elf_r_info             Elf32_r_info
 112 # define ELF_ST_BIND            ELF32_ST_BIND
 113 # define ELF_ST_TYPE            ELF32_ST_TYPE
 114 # define fn_ELF_R_SYM           fn_ELF32_R_SYM
 115 # define fn_ELF_R_INFO          fn_ELF32_R_INFO
 116 # define uint_t                 uint32_t
 117 # define _w                     w
 118 # define _align                 3u
 119 # define _size                  4
 120 #endif
 121
 122 /* Functions and pointers that do_file() may override for specific e_machine. */
 123 static int fn_is_fake_mcount(Elf_Rel const *rp)
 124 {
 125         return 0;
 126 }
 127 static int (*is_fake_mcount)(Elf_Rel const *rp) = fn_is_fake_mcount;
 128
 129 static uint_t fn_ELF_R_SYM(Elf_Rel const *rp)
 130 {
 131         return ELF_R_SYM(_w(rp->r_info));
 132 }
 133 static uint_t (*Elf_r_sym)(Elf_Rel const *rp) = fn_ELF_R_SYM;
 134
 135 static void fn_ELF_R_INFO(Elf_Rel *const rp, unsigned sym, unsigned type)
 136 {
 137         rp->r_info = _w(ELF_R_INFO(sym, type));
 138 }
 139 static void (*Elf_r_info)(Elf_Rel *const rp, unsigned sym, unsigned type) = fn_ELF_R_INFO;
 140
 141 static int mcount_adjust = 0;
 142
 143 /*
 144  * MIPS mcount long call has 2 _mcount symbols, only the position of the 1st
 145  * _mcount symbol is needed for dynamic function tracer, with it, to disable
 146  * tracing(ftrace_make_nop), the instruction in the position is replaced with
 147  * the "b label" instruction, to enable tracing(ftrace_make_call), replace the
 148  * instruction back. So, here, we set the 2nd one as fake and filter it.
 149  *
 150  * c:   3c030000        lui     v1,0x0          <-->    b       label
 151  *              c: R_MIPS_HI16  _mcount
 152  *              c: R_MIPS_NONE  *ABS*
 153  *              c: R_MIPS_NONE  *ABS*
 154  * 10:  64630000        daddiu  v1,v1,0
 155  *              10: R_MIPS_LO16 _mcount
 156  *              10: R_MIPS_NONE *ABS*
 157  *              10: R_MIPS_NONE *ABS*
 158  * 14:  03e0082d        move    at,ra
 159  * 18:  0060f809        jalr    v1
 160  * label:
 161  */
 162 #define MIPS_FAKEMCOUNT_OFFSET  4
 163
 164 static int MIPS_is_fake_mcount(Elf_Rel const *rp)
 165 {
 166         static Elf_Addr old_r_offset;
 167         Elf_Addr current_r_offset = _w(rp->r_offset);
 168         int is_fake;
 169
 170         is_fake = old_r_offset &&
 171                 (current_r_offset - old_r_offset == MIPS_FAKEMCOUNT_OFFSET);
 172         old_r_offset = current_r_offset;
 173
 174         return is_fake;
 175 }
 176
 177 /* Append the new shstrtab, Elf_Shdr[], __mcount_loc and its relocations. */
 178 static void append_func(Elf_Ehdr *const ehdr,
 179                         Elf_Shdr *const shstr,
 180                         uint_t const *const mloc0,
 181                         uint_t const *const mlocp,
 182                         Elf_Rel const *const mrel0,
 183                         Elf_Rel const *const mrelp,
 184                         unsigned int const rel_entsize,
 185                         unsigned int const symsec_sh_link)
 186 {
 187         /* Begin constructing output file */
 188         Elf_Shdr mcsec;
 189         char const *mc_name = (sizeof(Elf_Rela) == rel_entsize)
 190                 ? ".rela__mcount_loc"
 191                 :  ".rel__mcount_loc";
 192         unsigned const old_shnum = w2(ehdr->e_shnum);
 193         uint_t const old_shoff = _w(ehdr->e_shoff);
 194         uint_t const old_shstr_sh_size   = _w(shstr->sh_size);
 195         uint_t const old_shstr_sh_offset = _w(shstr->sh_offset);
 196         uint_t t = 1 + strlen(mc_name) + _w(shstr->sh_size);
 197         uint_t new_e_shoff;
 198
 199         shstr->sh_size = _w(t);
 200         shstr->sh_offset = _w(sb.st_size);
 201         t += sb.st_size;
 202         t += (_align & -t);  /* word-byte align */
 203         new_e_shoff = t;
 204
 205         /* body for new shstrtab */
 206         ulseek(fd_map, sb.st_size, SEEK_SET);
 207         uwrite(fd_map, old_shstr_sh_offset + (void *)ehdr, old_shstr_sh_size);
 208         uwrite(fd_map, mc_name, 1 + strlen(mc_name));
 209
 210         /* old(modified) Elf_Shdr table, word-byte aligned */
 211         ulseek(fd_map, t, SEEK_SET);
 212         t += sizeof(Elf_Shdr) * old_shnum;
 213         uwrite(fd_map, old_shoff + (void *)ehdr,
 214                sizeof(Elf_Shdr) * old_shnum);
 215
 216         /* new sections __mcount_loc and .rel__mcount_loc */
 217         t += 2*sizeof(mcsec);
 218         mcsec.sh_name = w((sizeof(Elf_Rela) == rel_entsize) + strlen(".rel")
 219                 + old_shstr_sh_size);
 220         mcsec.sh_type = w(SHT_PROGBITS);
 221         mcsec.sh_flags = _w(SHF_ALLOC);
 222         mcsec.sh_addr = 0;
 223         mcsec.sh_offset = _w(t);
 224         mcsec.sh_size = _w((void *)mlocp - (void *)mloc0);
 225         mcsec.sh_link = 0;
 226         mcsec.sh_info = 0;
 227         mcsec.sh_addralign = _w(_size);
 228         mcsec.sh_entsize = _w(_size);
 229         uwrite(fd_map, &mcsec, sizeof(mcsec));
 230
 231         mcsec.sh_name = w(old_shstr_sh_size);
 232         mcsec.sh_type = (sizeof(Elf_Rela) == rel_entsize)
 233                 ? w(SHT_RELA)
 234                 : w(SHT_REL);
 235         mcsec.sh_flags = 0;
 236         mcsec.sh_addr = 0;
 237         mcsec.sh_offset = _w((void *)mlocp - (void *)mloc0 + t);
 238         mcsec.sh_size   = _w((void *)mrelp - (void *)mrel0);
 239         mcsec.sh_link = w(symsec_sh_link);
 240         mcsec.sh_info = w(old_shnum);
 241         mcsec.sh_addralign = _w(_size);
 242         mcsec.sh_entsize = _w(rel_entsize);
 243         uwrite(fd_map, &mcsec, sizeof(mcsec));
 244
 245         uwrite(fd_map, mloc0, (void *)mlocp - (void *)mloc0);
 246         uwrite(fd_map, mrel0, (void *)mrelp - (void *)mrel0);
 247
 248         ehdr->e_shoff = _w(new_e_shoff);
 249         ehdr->e_shnum = w2(2 + w2(ehdr->e_shnum));  /* {.rel,}__mcount_loc */
 250         ulseek(fd_map, 0, SEEK_SET);
 251         uwrite(fd_map, ehdr, sizeof(*ehdr));
 252 }
 253
 254 static unsigned get_mcountsym(Elf_Sym const *const sym0,
 255                               Elf_Rel const *relp,
 256                               char const *const str0)
 257 {
 258         unsigned mcountsym = 0;
 259
 260         Elf_Sym const *const symp =
 261                 &sym0[Elf_r_sym(relp)];
 262         char const *symname = &str0[w(symp->st_name)];
 263         char const *mcount = gpfx == '_' ? "_mcount" : "mcount";
 264
 265         if (symname[0] == '.')
 266                 ++symname;  /* ppc64 hack */
 267         if (strcmp(mcount, symname) == 0 ||
 268             (altmcount && strcmp(altmcount, symname) == 0))
 269                 mcountsym = Elf_r_sym(relp);
 270
 271         return mcountsym;
 272 }
 273
 274 static void get_sym_str_and_relp(Elf_Shdr const *const relhdr,
 275                                  Elf_Ehdr const *const ehdr,
 276                                  Elf_Sym const **sym0,
 277                                  char const **str0,
 278                                  Elf_Rel const **relp)
 279 {
 280         Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff)
 281                 + (void *)ehdr);
 282         unsigned const symsec_sh_link = w(relhdr->sh_link);
 283         Elf_Shdr const *const symsec = &shdr0[symsec_sh_link];
 284         Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)];
 285         Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset)
 286                 + (void *)ehdr);
 287
 288         *sym0 = (Elf_Sym const *)(_w(symsec->sh_offset)
 289                                   + (void *)ehdr);
 290
 291         *str0 = (char const *)(_w(strsec->sh_offset)
 292                                + (void *)ehdr);
 293
 294         *relp = rel0;
 295 }
 296
 297 /*
 298  * Look at the relocations in order to find the calls to mcount.
 299  * Accumulate the section offsets that are found, and their relocation info,
 300  * onto the end of the existing arrays.
 301  */
 302 static uint_t *sift_rel_mcount(uint_t *mlocp,
 303                                unsigned const offbase,
 304                                Elf_Rel **const mrelpp,
 305                                Elf_Shdr const *const relhdr,
 306                                Elf_Ehdr const *const ehdr,
 307                                unsigned const recsym,
 308                                uint_t const recval,
 309                                unsigned const reltype)
 310 {
 311         uint_t *const mloc0 = mlocp;
 312         Elf_Rel *mrelp = *mrelpp;
 313         Elf_Sym const *sym0;
 314         char const *str0;
 315         Elf_Rel const *relp;
 316         unsigned rel_entsize = _w(relhdr->sh_entsize);
 317         unsigned const nrel = _w(relhdr->sh_size) / rel_entsize;
 318         unsigned mcountsym = 0;
 319         unsigned t;
 320
 321         get_sym_str_and_relp(relhdr, ehdr, &sym0, &str0, &relp);
 322
 323         for (t = nrel; t; --t) {
 324                 if (!mcountsym)
 325                         mcountsym = get_mcountsym(sym0, relp, str0);
 326
 327                 if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) {
 328                         uint_t const addend =
 329                                 _w(_w(relp->r_offset) - recval + mcount_adjust);
 330                         mrelp->r_offset = _w(offbase
 331                                 + ((void *)mlocp - (void *)mloc0));
 332                         Elf_r_info(mrelp, recsym, reltype);
 333                         if (rel_entsize == sizeof(Elf_Rela)) {
 334                                 ((Elf_Rela *)mrelp)->r_addend = addend;
 335                                 *mlocp++ = 0;
 336                         } else
 337                                 *mlocp++ = addend;
 338
 339                         mrelp = (Elf_Rel *)(rel_entsize + (void *)mrelp);
 340                 }
 341                 relp = (Elf_Rel const *)(rel_entsize + (void *)relp);
 342         }
 343         *mrelpp = mrelp;
 344         return mlocp;
 345 }
 346
 347 /*
 348  * Read the relocation table again, but this time its called on sections
 349  * that are not going to be traced. The mcount calls here will be converted
 350  * into nops.
 351  */
 352 static void nop_mcount(Elf_Shdr const *const relhdr,
 353                        Elf_Ehdr const *const ehdr,
 354                        const char *const txtname)
 355 {
 356         Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff)
 357                 + (void *)ehdr);
 358         Elf_Sym const *sym0;
 359         char const *str0;
 360         Elf_Rel const *relp;
 361         Elf_Shdr const *const shdr = &shdr0[w(relhdr->sh_info)];
 362         unsigned rel_entsize = _w(relhdr->sh_entsize);
 363         unsigned const nrel = _w(relhdr->sh_size) / rel_entsize;
 364         unsigned mcountsym = 0;
 365         unsigned t;
 366         int once = 0;
 367
 368         get_sym_str_and_relp(relhdr, ehdr, &sym0, &str0, &relp);
 369
 370         for (t = nrel; t; --t) {
 371                 int ret = -1;
 372
 373                 if (!mcountsym)
 374                         mcountsym = get_mcountsym(sym0, relp, str0);
 375
 376                 if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) {
 377                         if (make_nop)
 378                                 ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset);
 379                         if (warn_on_notrace_sect && !once) {
 380                                 printf("Section %s has mcount callers being ignored\n",
 381                                        txtname);
 382                                 once = 1;
 383                                 /* just warn? */
 384                                 if (!make_nop)
 385                                         return;
 386                         }
 387                 }
 388
 389                 /*
 390                  * If we successfully removed the mcount, mark the relocation
 391                  * as a nop (don't do anything with it).
 392                  */
 393                 if (!ret) {
 394                         Elf_Rel rel;
 395                         rel = *(Elf_Rel *)relp;
 396                         Elf_r_info(&rel, Elf_r_sym(relp), rel_type_nop);
 397                         ulseek(fd_map, (void *)relp - (void *)ehdr, SEEK_SET);
 398                         uwrite(fd_map, &rel, sizeof(rel));
 399                 }
 400                 relp = (Elf_Rel const *)(rel_entsize + (void *)relp);
 401         }
 402 }
 403
 404
 405 /*
 406  * Find a symbol in the given section, to be used as the base for relocating
 407  * the table of offsets of calls to mcount.  A local or global symbol suffices,
 408  * but avoid a Weak symbol because it may be overridden; the change in value
 409  * would invalidate the relocations of the offsets of the calls to mcount.
 410  * Often the found symbol will be the unnamed local symbol generated by
 411  * GNU 'as' for the start of each section.  For example:
 412  *    Num:    Value  Size Type    Bind   Vis      Ndx Name
 413  *      2: 00000000     0 SECTION LOCAL  DEFAULT    1
 414  */
 415 static unsigned find_secsym_ndx(unsigned const txtndx,
 416                                 char const *const txtname,
 417                                 uint_t *const recvalp,
 418                                 Elf_Shdr const *const symhdr,
 419                                 Elf_Ehdr const *const ehdr)
 420 {
 421         Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symhdr->sh_offset)
 422                 + (void *)ehdr);
 423         unsigned const nsym = _w(symhdr->sh_size) / _w(symhdr->sh_entsize);
 424         Elf_Sym const *symp;
 425         unsigned t;
 426
 427         for (symp = sym0, t = nsym; t; --t, ++symp) {
 428                 unsigned int const st_bind = ELF_ST_BIND(symp->st_info);
 429
 430                 if (txtndx == w2(symp->st_shndx)
 431                         /* avoid STB_WEAK */
 432                     && (STB_LOCAL == st_bind || STB_GLOBAL == st_bind)) {
 433                         /* function symbols on ARM have quirks, avoid them */
 434                         if (w2(ehdr->e_machine) == EM_ARM
 435                             && ELF_ST_TYPE(symp->st_info) == STT_FUNC)
 436                                 continue;
 437
 438                         *recvalp = _w(symp->st_value);
 439                         return symp - sym0;
 440                 }
 441         }
 442         fprintf(stderr, "Cannot find symbol for section %d: %s.\n",
 443                 txtndx, txtname);
 444         fail_file();
 445 }
 446
 447
 448 /* Evade ISO C restriction: no declaration after statement in has_rel_mcount. */
 449 static char const *
 450 __has_rel_mcount(Elf_Shdr const *const relhdr,  /* is SHT_REL or SHT_RELA */
 451                  Elf_Shdr const *const shdr0,
 452                  char const *const shstrtab,
 453                  char const *const fname)
 454 {
 455         /* .sh_info depends on .sh_type == SHT_REL[,A] */
 456         Elf_Shdr const *const txthdr = &shdr0[w(relhdr->sh_info)];
 457         char const *const txtname = &shstrtab[w(txthdr->sh_name)];
 458
 459         if (strcmp("__mcount_loc", txtname) == 0) {
 460                 fprintf(stderr, "warning: __mcount_loc already exists: %s\n",
 461                         fname);
 462                 succeed_file();
 463         }
 464         if (w(txthdr->sh_type) != SHT_PROGBITS ||
 465             !(w(txthdr->sh_flags) & SHF_EXECINSTR))
 466                 return NULL;
 467         return txtname;
 468 }
 469
 470 static char const *has_rel_mcount(Elf_Shdr const *const relhdr,
 471                                   Elf_Shdr const *const shdr0,
 472                                   char const *const shstrtab,
 473                                   char const *const fname)
 474 {
 475         if (w(relhdr->sh_type) != SHT_REL && w(relhdr->sh_type) != SHT_RELA)
 476                 return NULL;
 477         return __has_rel_mcount(relhdr, shdr0, shstrtab, fname);
 478 }
 479
 480
 481 static unsigned tot_relsize(Elf_Shdr const *const shdr0,
 482                             unsigned nhdr,
 483                             const char *const shstrtab,
 484                             const char *const fname)
 485 {
 486         unsigned totrelsz = 0;
 487         Elf_Shdr const *shdrp = shdr0;
 488         char const *txtname;
 489
 490         for (; nhdr; --nhdr, ++shdrp) {
 491                 txtname = has_rel_mcount(shdrp, shdr0, shstrtab, fname);
 492                 if (txtname && is_mcounted_section_name(txtname))
 493                         totrelsz += _w(shdrp->sh_size);
 494         }
 495         return totrelsz;
 496 }
 497
 498
 499 /* Overall supervision for Elf32 ET_REL file. */
 500 static void
 501 do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype)
 502 {
 503         Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff)
 504                 + (void *)ehdr);
 505         unsigned const nhdr = w2(ehdr->e_shnum);
 506         Elf_Shdr *const shstr = &shdr0[w2(ehdr->e_shstrndx)];
 507         char const *const shstrtab = (char const *)(_w(shstr->sh_offset)
 508                 + (void *)ehdr);
 509
 510         Elf_Shdr const *relhdr;
 511         unsigned k;
 512
 513         /* Upper bound on space: assume all relevant relocs are for mcount. */
 514         unsigned const totrelsz = tot_relsize(shdr0, nhdr, shstrtab, fname);
 515         Elf_Rel *const mrel0 = umalloc(totrelsz);
 516         Elf_Rel *      mrelp = mrel0;
 517
 518         /* 2*sizeof(address) <= sizeof(Elf_Rel) */
 519         uint_t *const mloc0 = umalloc(totrelsz>>1);
 520         uint_t *      mlocp = mloc0;
 521
 522         unsigned rel_entsize = 0;
 523         unsigned symsec_sh_link = 0;
 524
 525         for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) {
 526                 char const *const txtname = has_rel_mcount(relhdr, shdr0,
 527                         shstrtab, fname);
 528                 if (txtname && is_mcounted_section_name(txtname)) {
 529                         uint_t recval = 0;
 530                         unsigned const recsym = find_secsym_ndx(
 531                                 w(relhdr->sh_info), txtname, &recval,
 532                                 &shdr0[symsec_sh_link = w(relhdr->sh_link)],
 533                                 ehdr);
 534
 535                         rel_entsize = _w(relhdr->sh_entsize);
 536                         mlocp = sift_rel_mcount(mlocp,
 537                                 (void *)mlocp - (void *)mloc0, &mrelp,
 538                                 relhdr, ehdr, recsym, recval, reltype);
 539                 } else if (txtname && (warn_on_notrace_sect || make_nop)) {
 540                         /*
 541                          * This section is ignored by ftrace, but still
 542                          * has mcount calls. Convert them to nops now.
 543                          */
 544                         nop_mcount(relhdr, ehdr, txtname);
 545                 }
 546         }
 547         if (mloc0 != mlocp) {
 548                 append_func(ehdr, shstr, mloc0, mlocp, mrel0, mrelp,
 549                             rel_entsize, symsec_sh_link);
 550         }
 551         free(mrel0);
 552         free(mloc0);
 553 }