diff options
author | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
---|---|---|
committer | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
commit | c71c03bda1e86c9d5198c5d83f712e695c4f2a1e (patch) | |
tree | ecb166cb3e2b7e2adb3b5e292245fefd23381ac8 /scripts/recordmcount.h | |
parent | ea53c912f8a86a8567697115b6a0d8152beee5c8 (diff) | |
parent | 6a00f206debf8a5c8899055726ad127dbeeed098 (diff) |
Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp
Conflicts:
litmus/sched_cedf.c
Diffstat (limited to 'scripts/recordmcount.h')
-rw-r--r-- | scripts/recordmcount.h | 553 |
1 files changed, 553 insertions, 0 deletions
diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h new file mode 100644 index 000000000000..f40a6af6bf40 --- /dev/null +++ b/scripts/recordmcount.h | |||
@@ -0,0 +1,553 @@ | |||
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 | } | ||