Commit | Line | Data |
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4ea42b18 MH |
1 | /* |
2 | * probe-finder.c : C expression to kprobe event converter | |
3 | * | |
4 | * Written by Masami Hiramatsu <mhiramat@redhat.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
19 | * | |
20 | */ | |
21 | ||
22 | #include <sys/utsname.h> | |
23 | #include <sys/types.h> | |
24 | #include <sys/stat.h> | |
25 | #include <fcntl.h> | |
26 | #include <errno.h> | |
27 | #include <stdio.h> | |
28 | #include <unistd.h> | |
29 | #include <getopt.h> | |
30 | #include <stdlib.h> | |
31 | #include <string.h> | |
32 | #include <stdarg.h> | |
33 | #include <ctype.h> | |
074fc0e4 | 34 | |
89c69c0e MH |
35 | #include "event.h" |
36 | #include "debug.h" | |
074fc0e4 | 37 | #include "util.h" |
4ea42b18 MH |
38 | #include "probe-finder.h" |
39 | ||
40 | ||
41 | /* Dwarf_Die Linkage to parent Die */ | |
42 | struct die_link { | |
43 | struct die_link *parent; /* Parent die */ | |
44 | Dwarf_Die die; /* Current die */ | |
45 | }; | |
46 | ||
47 | static Dwarf_Debug __dw_debug; | |
48 | static Dwarf_Error __dw_error; | |
49 | ||
4ea42b18 MH |
50 | /* |
51 | * Generic dwarf analysis helpers | |
52 | */ | |
53 | ||
54 | #define X86_32_MAX_REGS 8 | |
55 | const char *x86_32_regs_table[X86_32_MAX_REGS] = { | |
56 | "%ax", | |
57 | "%cx", | |
58 | "%dx", | |
59 | "%bx", | |
60 | "$stack", /* Stack address instead of %sp */ | |
61 | "%bp", | |
62 | "%si", | |
63 | "%di", | |
64 | }; | |
65 | ||
66 | #define X86_64_MAX_REGS 16 | |
67 | const char *x86_64_regs_table[X86_64_MAX_REGS] = { | |
68 | "%ax", | |
69 | "%dx", | |
70 | "%cx", | |
71 | "%bx", | |
72 | "%si", | |
73 | "%di", | |
74 | "%bp", | |
75 | "%sp", | |
76 | "%r8", | |
77 | "%r9", | |
78 | "%r10", | |
79 | "%r11", | |
80 | "%r12", | |
81 | "%r13", | |
82 | "%r14", | |
83 | "%r15", | |
84 | }; | |
85 | ||
86 | /* TODO: switching by dwarf address size */ | |
87 | #ifdef __x86_64__ | |
88 | #define ARCH_MAX_REGS X86_64_MAX_REGS | |
89 | #define arch_regs_table x86_64_regs_table | |
90 | #else | |
91 | #define ARCH_MAX_REGS X86_32_MAX_REGS | |
92 | #define arch_regs_table x86_32_regs_table | |
93 | #endif | |
94 | ||
95 | /* Return architecture dependent register string (for kprobe-tracer) */ | |
96 | static const char *get_arch_regstr(unsigned int n) | |
97 | { | |
98 | return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL; | |
99 | } | |
100 | ||
101 | /* | |
102 | * Compare the tail of two strings. | |
103 | * Return 0 if whole of either string is same as another's tail part. | |
104 | */ | |
105 | static int strtailcmp(const char *s1, const char *s2) | |
106 | { | |
107 | int i1 = strlen(s1); | |
108 | int i2 = strlen(s2); | |
109 | while (--i1 > 0 && --i2 > 0) { | |
110 | if (s1[i1] != s2[i2]) | |
111 | return s1[i1] - s2[i2]; | |
112 | } | |
113 | return 0; | |
114 | } | |
115 | ||
116 | /* Find the fileno of the target file. */ | |
b0ef0732 | 117 | static Dwarf_Unsigned cu_find_fileno(Dwarf_Die cu_die, const char *fname) |
4ea42b18 MH |
118 | { |
119 | Dwarf_Signed cnt, i; | |
120 | Dwarf_Unsigned found = 0; | |
121 | char **srcs; | |
122 | int ret; | |
123 | ||
124 | if (!fname) | |
125 | return 0; | |
126 | ||
127 | ret = dwarf_srcfiles(cu_die, &srcs, &cnt, &__dw_error); | |
128 | if (ret == DW_DLV_OK) { | |
129 | for (i = 0; i < cnt && !found; i++) { | |
130 | if (strtailcmp(srcs[i], fname) == 0) | |
131 | found = i + 1; | |
132 | dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING); | |
133 | } | |
134 | for (; i < cnt; i++) | |
135 | dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING); | |
136 | dwarf_dealloc(__dw_debug, srcs, DW_DLA_LIST); | |
137 | } | |
138 | if (found) | |
b7cb10e7 | 139 | pr_debug("found fno: %d\n", (int)found); |
4ea42b18 MH |
140 | return found; |
141 | } | |
142 | ||
143 | /* Compare diename and tname */ | |
074fc0e4 | 144 | static int die_compare_name(Dwarf_Die dw_die, const char *tname) |
4ea42b18 MH |
145 | { |
146 | char *name; | |
147 | int ret; | |
074fc0e4 | 148 | ret = dwarf_diename(dw_die, &name, &__dw_error); |
9769833b | 149 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
150 | if (ret == DW_DLV_OK) { |
151 | ret = strcmp(tname, name); | |
152 | dwarf_dealloc(__dw_debug, name, DW_DLA_STRING); | |
153 | } else | |
154 | ret = -1; | |
155 | return ret; | |
156 | } | |
157 | ||
158 | /* Check the address is in the subprogram(function). */ | |
159 | static int die_within_subprogram(Dwarf_Die sp_die, Dwarf_Addr addr, | |
160 | Dwarf_Signed *offs) | |
161 | { | |
162 | Dwarf_Addr lopc, hipc; | |
163 | int ret; | |
164 | ||
165 | /* TODO: check ranges */ | |
166 | ret = dwarf_lowpc(sp_die, &lopc, &__dw_error); | |
9769833b | 167 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
168 | if (ret == DW_DLV_NO_ENTRY) |
169 | return 0; | |
170 | ret = dwarf_highpc(sp_die, &hipc, &__dw_error); | |
9769833b | 171 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
172 | if (lopc <= addr && addr < hipc) { |
173 | *offs = addr - lopc; | |
174 | return 1; | |
175 | } else | |
176 | return 0; | |
177 | } | |
178 | ||
179 | /* Check the die is inlined function */ | |
074fc0e4 | 180 | static Dwarf_Bool die_inlined_subprogram(Dwarf_Die dw_die) |
4ea42b18 MH |
181 | { |
182 | /* TODO: check strictly */ | |
183 | Dwarf_Bool inl; | |
184 | int ret; | |
185 | ||
074fc0e4 | 186 | ret = dwarf_hasattr(dw_die, DW_AT_inline, &inl, &__dw_error); |
9769833b | 187 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
188 | return inl; |
189 | } | |
190 | ||
191 | /* Get the offset of abstruct_origin */ | |
074fc0e4 | 192 | static Dwarf_Off die_get_abstract_origin(Dwarf_Die dw_die) |
4ea42b18 MH |
193 | { |
194 | Dwarf_Attribute attr; | |
195 | Dwarf_Off cu_offs; | |
196 | int ret; | |
197 | ||
074fc0e4 | 198 | ret = dwarf_attr(dw_die, DW_AT_abstract_origin, &attr, &__dw_error); |
9769833b | 199 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 | 200 | ret = dwarf_formref(attr, &cu_offs, &__dw_error); |
9769833b | 201 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
202 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); |
203 | return cu_offs; | |
204 | } | |
205 | ||
206 | /* Get entry pc(or low pc, 1st entry of ranges) of the die */ | |
074fc0e4 | 207 | static Dwarf_Addr die_get_entrypc(Dwarf_Die dw_die) |
4ea42b18 MH |
208 | { |
209 | Dwarf_Attribute attr; | |
210 | Dwarf_Addr addr; | |
211 | Dwarf_Off offs; | |
212 | Dwarf_Ranges *ranges; | |
213 | Dwarf_Signed cnt; | |
214 | int ret; | |
215 | ||
216 | /* Try to get entry pc */ | |
074fc0e4 | 217 | ret = dwarf_attr(dw_die, DW_AT_entry_pc, &attr, &__dw_error); |
9769833b | 218 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
219 | if (ret == DW_DLV_OK) { |
220 | ret = dwarf_formaddr(attr, &addr, &__dw_error); | |
9769833b | 221 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
222 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); |
223 | return addr; | |
224 | } | |
225 | ||
226 | /* Try to get low pc */ | |
074fc0e4 | 227 | ret = dwarf_lowpc(dw_die, &addr, &__dw_error); |
9769833b | 228 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
229 | if (ret == DW_DLV_OK) |
230 | return addr; | |
231 | ||
232 | /* Try to get ranges */ | |
074fc0e4 | 233 | ret = dwarf_attr(dw_die, DW_AT_ranges, &attr, &__dw_error); |
9769833b | 234 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 | 235 | ret = dwarf_formref(attr, &offs, &__dw_error); |
9769833b | 236 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
237 | ret = dwarf_get_ranges(__dw_debug, offs, &ranges, &cnt, NULL, |
238 | &__dw_error); | |
9769833b | 239 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
240 | addr = ranges[0].dwr_addr1; |
241 | dwarf_ranges_dealloc(__dw_debug, ranges, cnt); | |
242 | return addr; | |
243 | } | |
244 | ||
245 | /* | |
246 | * Search a Die from Die tree. | |
247 | * Note: cur_link->die should be deallocated in this function. | |
248 | */ | |
249 | static int __search_die_tree(struct die_link *cur_link, | |
250 | int (*die_cb)(struct die_link *, void *), | |
251 | void *data) | |
252 | { | |
253 | Dwarf_Die new_die; | |
254 | struct die_link new_link; | |
255 | int ret; | |
256 | ||
257 | if (!die_cb) | |
258 | return 0; | |
259 | ||
260 | /* Check current die */ | |
261 | while (!(ret = die_cb(cur_link, data))) { | |
262 | /* Check child die */ | |
263 | ret = dwarf_child(cur_link->die, &new_die, &__dw_error); | |
9769833b | 264 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
265 | if (ret == DW_DLV_OK) { |
266 | new_link.parent = cur_link; | |
267 | new_link.die = new_die; | |
268 | ret = __search_die_tree(&new_link, die_cb, data); | |
269 | if (ret) | |
270 | break; | |
271 | } | |
272 | ||
273 | /* Move to next sibling */ | |
274 | ret = dwarf_siblingof(__dw_debug, cur_link->die, &new_die, | |
275 | &__dw_error); | |
9769833b | 276 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
277 | dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE); |
278 | cur_link->die = new_die; | |
279 | if (ret == DW_DLV_NO_ENTRY) | |
280 | return 0; | |
281 | } | |
282 | dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE); | |
283 | return ret; | |
284 | } | |
285 | ||
286 | /* Search a die in its children's die tree */ | |
287 | static int search_die_from_children(Dwarf_Die parent_die, | |
288 | int (*die_cb)(struct die_link *, void *), | |
289 | void *data) | |
290 | { | |
291 | struct die_link new_link; | |
292 | int ret; | |
293 | ||
294 | new_link.parent = NULL; | |
295 | ret = dwarf_child(parent_die, &new_link.die, &__dw_error); | |
9769833b | 296 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
297 | if (ret == DW_DLV_OK) |
298 | return __search_die_tree(&new_link, die_cb, data); | |
299 | else | |
300 | return 0; | |
301 | } | |
302 | ||
303 | /* Find a locdesc corresponding to the address */ | |
304 | static int attr_get_locdesc(Dwarf_Attribute attr, Dwarf_Locdesc *desc, | |
305 | Dwarf_Addr addr) | |
306 | { | |
307 | Dwarf_Signed lcnt; | |
308 | Dwarf_Locdesc **llbuf; | |
309 | int ret, i; | |
310 | ||
311 | ret = dwarf_loclist_n(attr, &llbuf, &lcnt, &__dw_error); | |
9769833b | 312 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
313 | ret = DW_DLV_NO_ENTRY; |
314 | for (i = 0; i < lcnt; ++i) { | |
315 | if (llbuf[i]->ld_lopc <= addr && | |
316 | llbuf[i]->ld_hipc > addr) { | |
317 | memcpy(desc, llbuf[i], sizeof(Dwarf_Locdesc)); | |
318 | desc->ld_s = | |
319 | malloc(sizeof(Dwarf_Loc) * llbuf[i]->ld_cents); | |
9769833b | 320 | DIE_IF(desc->ld_s == NULL); |
4ea42b18 MH |
321 | memcpy(desc->ld_s, llbuf[i]->ld_s, |
322 | sizeof(Dwarf_Loc) * llbuf[i]->ld_cents); | |
323 | ret = DW_DLV_OK; | |
324 | break; | |
325 | } | |
326 | dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK); | |
327 | dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC); | |
328 | } | |
329 | /* Releasing loop */ | |
330 | for (; i < lcnt; ++i) { | |
331 | dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK); | |
332 | dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC); | |
333 | } | |
334 | dwarf_dealloc(__dw_debug, llbuf, DW_DLA_LIST); | |
335 | return ret; | |
336 | } | |
337 | ||
b0ef0732 MH |
338 | /* Get decl_file attribute value (file number) */ |
339 | static Dwarf_Unsigned die_get_decl_file(Dwarf_Die sp_die) | |
340 | { | |
341 | Dwarf_Attribute attr; | |
342 | Dwarf_Unsigned fno; | |
343 | int ret; | |
344 | ||
345 | ret = dwarf_attr(sp_die, DW_AT_decl_file, &attr, &__dw_error); | |
346 | DIE_IF(ret != DW_DLV_OK); | |
347 | dwarf_formudata(attr, &fno, &__dw_error); | |
348 | DIE_IF(ret != DW_DLV_OK); | |
349 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
350 | return fno; | |
351 | } | |
352 | ||
353 | /* Get decl_line attribute value (line number) */ | |
354 | static Dwarf_Unsigned die_get_decl_line(Dwarf_Die sp_die) | |
355 | { | |
356 | Dwarf_Attribute attr; | |
357 | Dwarf_Unsigned lno; | |
358 | int ret; | |
359 | ||
360 | ret = dwarf_attr(sp_die, DW_AT_decl_line, &attr, &__dw_error); | |
361 | DIE_IF(ret != DW_DLV_OK); | |
362 | dwarf_formudata(attr, &lno, &__dw_error); | |
363 | DIE_IF(ret != DW_DLV_OK); | |
364 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
365 | return lno; | |
366 | } | |
367 | ||
4ea42b18 MH |
368 | /* |
369 | * Probe finder related functions | |
370 | */ | |
371 | ||
372 | /* Show a location */ | |
373 | static void show_location(Dwarf_Loc *loc, struct probe_finder *pf) | |
374 | { | |
375 | Dwarf_Small op; | |
376 | Dwarf_Unsigned regn; | |
377 | Dwarf_Signed offs; | |
378 | int deref = 0, ret; | |
379 | const char *regs; | |
380 | ||
381 | op = loc->lr_atom; | |
382 | ||
383 | /* If this is based on frame buffer, set the offset */ | |
384 | if (op == DW_OP_fbreg) { | |
385 | deref = 1; | |
386 | offs = (Dwarf_Signed)loc->lr_number; | |
387 | op = pf->fbloc.ld_s[0].lr_atom; | |
388 | loc = &pf->fbloc.ld_s[0]; | |
389 | } else | |
390 | offs = 0; | |
391 | ||
392 | if (op >= DW_OP_breg0 && op <= DW_OP_breg31) { | |
393 | regn = op - DW_OP_breg0; | |
394 | offs += (Dwarf_Signed)loc->lr_number; | |
395 | deref = 1; | |
396 | } else if (op >= DW_OP_reg0 && op <= DW_OP_reg31) { | |
397 | regn = op - DW_OP_reg0; | |
398 | } else if (op == DW_OP_bregx) { | |
399 | regn = loc->lr_number; | |
400 | offs += (Dwarf_Signed)loc->lr_number2; | |
401 | deref = 1; | |
402 | } else if (op == DW_OP_regx) { | |
403 | regn = loc->lr_number; | |
404 | } else | |
074fc0e4 | 405 | die("Dwarf_OP %d is not supported.\n", op); |
4ea42b18 MH |
406 | |
407 | regs = get_arch_regstr(regn); | |
408 | if (!regs) | |
074fc0e4 | 409 | die("%lld exceeds max register number.\n", regn); |
4ea42b18 MH |
410 | |
411 | if (deref) | |
412 | ret = snprintf(pf->buf, pf->len, | |
413 | " %s=%+lld(%s)", pf->var, offs, regs); | |
414 | else | |
415 | ret = snprintf(pf->buf, pf->len, " %s=%s", pf->var, regs); | |
9769833b MH |
416 | DIE_IF(ret < 0); |
417 | DIE_IF(ret >= pf->len); | |
4ea42b18 MH |
418 | } |
419 | ||
420 | /* Show a variables in kprobe event format */ | |
421 | static void show_variable(Dwarf_Die vr_die, struct probe_finder *pf) | |
422 | { | |
423 | Dwarf_Attribute attr; | |
424 | Dwarf_Locdesc ld; | |
425 | int ret; | |
426 | ||
427 | ret = dwarf_attr(vr_die, DW_AT_location, &attr, &__dw_error); | |
428 | if (ret != DW_DLV_OK) | |
429 | goto error; | |
430 | ret = attr_get_locdesc(attr, &ld, (pf->addr - pf->cu_base)); | |
431 | if (ret != DW_DLV_OK) | |
432 | goto error; | |
433 | /* TODO? */ | |
9769833b | 434 | DIE_IF(ld.ld_cents != 1); |
4ea42b18 MH |
435 | show_location(&ld.ld_s[0], pf); |
436 | free(ld.ld_s); | |
437 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
438 | return ; | |
439 | error: | |
074fc0e4 MH |
440 | die("Failed to find the location of %s at this address.\n" |
441 | " Perhaps, it has been optimized out.\n", pf->var); | |
4ea42b18 MH |
442 | } |
443 | ||
444 | static int variable_callback(struct die_link *dlink, void *data) | |
445 | { | |
446 | struct probe_finder *pf = (struct probe_finder *)data; | |
447 | Dwarf_Half tag; | |
448 | int ret; | |
449 | ||
450 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
9769833b | 451 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
452 | if ((tag == DW_TAG_formal_parameter || |
453 | tag == DW_TAG_variable) && | |
454 | (die_compare_name(dlink->die, pf->var) == 0)) { | |
455 | show_variable(dlink->die, pf); | |
456 | return 1; | |
457 | } | |
458 | /* TODO: Support struct members and arrays */ | |
459 | return 0; | |
460 | } | |
461 | ||
462 | /* Find a variable in a subprogram die */ | |
463 | static void find_variable(Dwarf_Die sp_die, struct probe_finder *pf) | |
464 | { | |
465 | int ret; | |
466 | ||
467 | if (!is_c_varname(pf->var)) { | |
468 | /* Output raw parameters */ | |
469 | ret = snprintf(pf->buf, pf->len, " %s", pf->var); | |
9769833b MH |
470 | DIE_IF(ret < 0); |
471 | DIE_IF(ret >= pf->len); | |
4ea42b18 MH |
472 | return ; |
473 | } | |
474 | ||
b7cb10e7 | 475 | pr_debug("Searching '%s' variable in context.\n", pf->var); |
4ea42b18 MH |
476 | /* Search child die for local variables and parameters. */ |
477 | ret = search_die_from_children(sp_die, variable_callback, pf); | |
478 | if (!ret) | |
074fc0e4 | 479 | die("Failed to find '%s' in this function.\n", pf->var); |
4ea42b18 MH |
480 | } |
481 | ||
482 | /* Get a frame base on the address */ | |
483 | static void get_current_frame_base(Dwarf_Die sp_die, struct probe_finder *pf) | |
484 | { | |
485 | Dwarf_Attribute attr; | |
486 | int ret; | |
487 | ||
488 | ret = dwarf_attr(sp_die, DW_AT_frame_base, &attr, &__dw_error); | |
9769833b | 489 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 | 490 | ret = attr_get_locdesc(attr, &pf->fbloc, (pf->addr - pf->cu_base)); |
9769833b | 491 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
492 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); |
493 | } | |
494 | ||
495 | static void free_current_frame_base(struct probe_finder *pf) | |
496 | { | |
497 | free(pf->fbloc.ld_s); | |
498 | memset(&pf->fbloc, 0, sizeof(Dwarf_Locdesc)); | |
499 | } | |
500 | ||
501 | /* Show a probe point to output buffer */ | |
502 | static void show_probepoint(Dwarf_Die sp_die, Dwarf_Signed offs, | |
503 | struct probe_finder *pf) | |
504 | { | |
505 | struct probe_point *pp = pf->pp; | |
506 | char *name; | |
507 | char tmp[MAX_PROBE_BUFFER]; | |
508 | int ret, i, len; | |
509 | ||
510 | /* Output name of probe point */ | |
511 | ret = dwarf_diename(sp_die, &name, &__dw_error); | |
9769833b | 512 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
513 | if (ret == DW_DLV_OK) { |
514 | ret = snprintf(tmp, MAX_PROBE_BUFFER, "%s+%u", name, | |
515 | (unsigned int)offs); | |
253977b0 MH |
516 | /* Copy the function name if possible */ |
517 | if (!pp->function) { | |
518 | pp->function = strdup(name); | |
519 | pp->offset = offs; | |
520 | } | |
4ea42b18 MH |
521 | dwarf_dealloc(__dw_debug, name, DW_DLA_STRING); |
522 | } else { | |
523 | /* This function has no name. */ | |
524 | ret = snprintf(tmp, MAX_PROBE_BUFFER, "0x%llx", pf->addr); | |
253977b0 MH |
525 | if (!pp->function) { |
526 | /* TODO: Use _stext */ | |
527 | pp->function = strdup(""); | |
528 | pp->offset = (int)pf->addr; | |
529 | } | |
4ea42b18 | 530 | } |
9769833b MH |
531 | DIE_IF(ret < 0); |
532 | DIE_IF(ret >= MAX_PROBE_BUFFER); | |
4ea42b18 | 533 | len = ret; |
b0ef0732 | 534 | pr_debug("Probe point found: %s\n", tmp); |
4ea42b18 MH |
535 | |
536 | /* Find each argument */ | |
537 | get_current_frame_base(sp_die, pf); | |
538 | for (i = 0; i < pp->nr_args; i++) { | |
539 | pf->var = pp->args[i]; | |
540 | pf->buf = &tmp[len]; | |
541 | pf->len = MAX_PROBE_BUFFER - len; | |
542 | find_variable(sp_die, pf); | |
543 | len += strlen(pf->buf); | |
544 | } | |
545 | free_current_frame_base(pf); | |
546 | ||
547 | pp->probes[pp->found] = strdup(tmp); | |
548 | pp->found++; | |
549 | } | |
550 | ||
551 | static int probeaddr_callback(struct die_link *dlink, void *data) | |
552 | { | |
553 | struct probe_finder *pf = (struct probe_finder *)data; | |
554 | Dwarf_Half tag; | |
555 | Dwarf_Signed offs; | |
556 | int ret; | |
557 | ||
558 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
9769833b | 559 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
560 | /* Check the address is in this subprogram */ |
561 | if (tag == DW_TAG_subprogram && | |
562 | die_within_subprogram(dlink->die, pf->addr, &offs)) { | |
563 | show_probepoint(dlink->die, offs, pf); | |
564 | return 1; | |
565 | } | |
566 | return 0; | |
567 | } | |
568 | ||
569 | /* Find probe point from its line number */ | |
b0ef0732 | 570 | static void find_by_line(struct probe_finder *pf) |
4ea42b18 | 571 | { |
b0ef0732 | 572 | Dwarf_Signed cnt, i, clm; |
4ea42b18 MH |
573 | Dwarf_Line *lines; |
574 | Dwarf_Unsigned lineno = 0; | |
575 | Dwarf_Addr addr; | |
576 | Dwarf_Unsigned fno; | |
577 | int ret; | |
578 | ||
b0ef0732 | 579 | ret = dwarf_srclines(pf->cu_die, &lines, &cnt, &__dw_error); |
9769833b | 580 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
581 | |
582 | for (i = 0; i < cnt; i++) { | |
583 | ret = dwarf_line_srcfileno(lines[i], &fno, &__dw_error); | |
9769833b | 584 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
585 | if (fno != pf->fno) |
586 | continue; | |
587 | ||
588 | ret = dwarf_lineno(lines[i], &lineno, &__dw_error); | |
9769833b | 589 | DIE_IF(ret != DW_DLV_OK); |
b0ef0732 | 590 | if (lineno != pf->lno) |
4ea42b18 MH |
591 | continue; |
592 | ||
b0ef0732 MH |
593 | ret = dwarf_lineoff(lines[i], &clm, &__dw_error); |
594 | DIE_IF(ret != DW_DLV_OK); | |
595 | ||
4ea42b18 | 596 | ret = dwarf_lineaddr(lines[i], &addr, &__dw_error); |
9769833b | 597 | DIE_IF(ret != DW_DLV_OK); |
b0ef0732 MH |
598 | pr_debug("Probe line found: line[%d]:%u,%d addr:0x%llx\n", |
599 | (int)i, (unsigned)lineno, (int)clm, addr); | |
4ea42b18 MH |
600 | pf->addr = addr; |
601 | /* Search a real subprogram including this line, */ | |
b0ef0732 MH |
602 | ret = search_die_from_children(pf->cu_die, |
603 | probeaddr_callback, pf); | |
4ea42b18 | 604 | if (ret == 0) |
074fc0e4 | 605 | die("Probe point is not found in subprograms.\n"); |
4ea42b18 MH |
606 | /* Continuing, because target line might be inlined. */ |
607 | } | |
608 | dwarf_srclines_dealloc(__dw_debug, lines, cnt); | |
609 | } | |
610 | ||
611 | /* Search function from function name */ | |
612 | static int probefunc_callback(struct die_link *dlink, void *data) | |
613 | { | |
614 | struct probe_finder *pf = (struct probe_finder *)data; | |
615 | struct probe_point *pp = pf->pp; | |
616 | struct die_link *lk; | |
617 | Dwarf_Signed offs; | |
618 | Dwarf_Half tag; | |
619 | int ret; | |
620 | ||
621 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
9769833b | 622 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
623 | if (tag == DW_TAG_subprogram) { |
624 | if (die_compare_name(dlink->die, pp->function) == 0) { | |
b0ef0732 MH |
625 | if (pp->line) { /* Function relative line */ |
626 | pf->fno = die_get_decl_file(dlink->die); | |
627 | pf->lno = die_get_decl_line(dlink->die) | |
628 | + pp->line; | |
629 | find_by_line(pf); | |
630 | return 1; | |
631 | } | |
4ea42b18 MH |
632 | if (die_inlined_subprogram(dlink->die)) { |
633 | /* Inlined function, save it. */ | |
634 | ret = dwarf_die_CU_offset(dlink->die, | |
635 | &pf->inl_offs, | |
636 | &__dw_error); | |
9769833b | 637 | DIE_IF(ret != DW_DLV_OK); |
b7cb10e7 ACM |
638 | pr_debug("inline definition offset %lld\n", |
639 | pf->inl_offs); | |
8030c5f5 | 640 | return 0; /* Continue to search */ |
4ea42b18 MH |
641 | } |
642 | /* Get probe address */ | |
643 | pf->addr = die_get_entrypc(dlink->die); | |
644 | pf->addr += pp->offset; | |
645 | /* TODO: Check the address in this function */ | |
646 | show_probepoint(dlink->die, pp->offset, pf); | |
8030c5f5 | 647 | return 1; /* Exit; no same symbol in this CU. */ |
4ea42b18 MH |
648 | } |
649 | } else if (tag == DW_TAG_inlined_subroutine && pf->inl_offs) { | |
650 | if (die_get_abstract_origin(dlink->die) == pf->inl_offs) { | |
651 | /* Get probe address */ | |
652 | pf->addr = die_get_entrypc(dlink->die); | |
653 | pf->addr += pp->offset; | |
b7cb10e7 | 654 | pr_debug("found inline addr: 0x%llx\n", pf->addr); |
4ea42b18 MH |
655 | /* Inlined function. Get a real subprogram */ |
656 | for (lk = dlink->parent; lk != NULL; lk = lk->parent) { | |
657 | tag = 0; | |
658 | dwarf_tag(lk->die, &tag, &__dw_error); | |
9769833b | 659 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
660 | if (tag == DW_TAG_subprogram && |
661 | !die_inlined_subprogram(lk->die)) | |
662 | goto found; | |
663 | } | |
074fc0e4 | 664 | die("Failed to find real subprogram.\n"); |
4ea42b18 MH |
665 | found: |
666 | /* Get offset from subprogram */ | |
667 | ret = die_within_subprogram(lk->die, pf->addr, &offs); | |
9769833b | 668 | DIE_IF(!ret); |
4ea42b18 MH |
669 | show_probepoint(lk->die, offs, pf); |
670 | /* Continue to search */ | |
671 | } | |
672 | } | |
673 | return 0; | |
674 | } | |
675 | ||
b0ef0732 | 676 | static void find_by_func(struct probe_finder *pf) |
4ea42b18 | 677 | { |
b0ef0732 | 678 | search_die_from_children(pf->cu_die, probefunc_callback, pf); |
4ea42b18 MH |
679 | } |
680 | ||
681 | /* Find a probe point */ | |
682 | int find_probepoint(int fd, struct probe_point *pp) | |
683 | { | |
684 | Dwarf_Half addr_size = 0; | |
685 | Dwarf_Unsigned next_cuh = 0; | |
4ea42b18 MH |
686 | int cu_number = 0, ret; |
687 | struct probe_finder pf = {.pp = pp}; | |
688 | ||
689 | ret = dwarf_init(fd, DW_DLC_READ, 0, 0, &__dw_debug, &__dw_error); | |
a225a1d9 MH |
690 | if (ret != DW_DLV_OK) { |
691 | pr_warning("No dwarf info found in the vmlinux - please rebuild with CONFIG_DEBUG_INFO.\n"); | |
692 | return -ENOENT; | |
693 | } | |
4ea42b18 MH |
694 | |
695 | pp->found = 0; | |
696 | while (++cu_number) { | |
697 | /* Search CU (Compilation Unit) */ | |
698 | ret = dwarf_next_cu_header(__dw_debug, NULL, NULL, NULL, | |
699 | &addr_size, &next_cuh, &__dw_error); | |
9769833b | 700 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
701 | if (ret == DW_DLV_NO_ENTRY) |
702 | break; | |
703 | ||
704 | /* Get the DIE(Debugging Information Entry) of this CU */ | |
b0ef0732 | 705 | ret = dwarf_siblingof(__dw_debug, 0, &pf.cu_die, &__dw_error); |
9769833b | 706 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
707 | |
708 | /* Check if target file is included. */ | |
709 | if (pp->file) | |
b0ef0732 | 710 | pf.fno = cu_find_fileno(pf.cu_die, pp->file); |
4ea42b18 MH |
711 | |
712 | if (!pp->file || pf.fno) { | |
713 | /* Save CU base address (for frame_base) */ | |
b0ef0732 | 714 | ret = dwarf_lowpc(pf.cu_die, &pf.cu_base, &__dw_error); |
9769833b | 715 | DIE_IF(ret == DW_DLV_ERROR); |
4ea42b18 MH |
716 | if (ret == DW_DLV_NO_ENTRY) |
717 | pf.cu_base = 0; | |
4ea42b18 | 718 | if (pp->function) |
b0ef0732 MH |
719 | find_by_func(&pf); |
720 | else { | |
721 | pf.lno = pp->line; | |
722 | find_by_line(&pf); | |
723 | } | |
4ea42b18 | 724 | } |
b0ef0732 | 725 | dwarf_dealloc(__dw_debug, pf.cu_die, DW_DLA_DIE); |
4ea42b18 MH |
726 | } |
727 | ret = dwarf_finish(__dw_debug, &__dw_error); | |
9769833b | 728 | DIE_IF(ret != DW_DLV_OK); |
4ea42b18 MH |
729 | |
730 | return pp->found; | |
731 | } | |
732 |