1 // SPDX-License-Identifier: GPL-2.0 <<
2 #include <linux/compiler.h> 1 #include <linux/compiler.h>
3 #include <elfutils/libdw.h> 2 #include <elfutils/libdw.h>
4 #include <elfutils/libdwfl.h> 3 #include <elfutils/libdwfl.h>
5 #include <inttypes.h> 4 #include <inttypes.h>
6 #include <errno.h> 5 #include <errno.h>
7 #include "debug.h" 6 #include "debug.h"
8 #include "dso.h" <<
9 #include "unwind.h" 7 #include "unwind.h"
10 #include "unwind-libdw.h" 8 #include "unwind-libdw.h"
11 #include "machine.h" 9 #include "machine.h"
12 #include "map.h" <<
13 #include "symbol.h" <<
14 #include "thread.h" 10 #include "thread.h"
15 #include <linux/types.h> 11 #include <linux/types.h>
16 #include <linux/zalloc.h> <<
17 #include "event.h" 12 #include "event.h"
18 #include "perf_regs.h" 13 #include "perf_regs.h"
19 #include "callchain.h" 14 #include "callchain.h"
20 #include "util/env.h" <<
21 15
22 static char *debuginfo_path; 16 static char *debuginfo_path;
23 17
24 static int __find_debuginfo(Dwfl_Module *mod _ <<
25 const char *modnam <<
26 const char *file_n <<
27 GElf_Word debuglin <<
28 { <<
29 const struct dso *dso = *userdata; <<
30 <<
31 assert(dso); <<
32 if (dso__symsrc_filename(dso) && strcm <<
33 *debuginfo_file_name = strdup( <<
34 return -1; <<
35 } <<
36 <<
37 static const Dwfl_Callbacks offline_callbacks 18 static const Dwfl_Callbacks offline_callbacks = {
38 .find_debuginfo = __find_debug !! 19 .find_debuginfo = dwfl_standard_find_debuginfo,
39 .debuginfo_path = &debuginfo_p 20 .debuginfo_path = &debuginfo_path,
40 .section_address = dwfl_offline 21 .section_address = dwfl_offline_section_address,
41 // .find_elf is not set as we use dwfl <<
42 }; 22 };
43 23
44 static int __report_module(struct addr_locatio 24 static int __report_module(struct addr_location *al, u64 ip,
45 struct unwind_info 25 struct unwind_info *ui)
46 { 26 {
47 Dwfl_Module *mod; 27 Dwfl_Module *mod;
48 struct dso *dso = NULL; 28 struct dso *dso = NULL;
49 Dwarf_Addr base; !! 29
50 /* !! 30 thread__find_addr_location(ui->thread,
51 * Some callers will use al->sym, so w !! 31 PERF_RECORD_MISC_USER,
52 * cheaper thread__find_map() here. !! 32 MAP__FUNCTION, ip, al);
53 */ <<
54 thread__find_symbol(ui->thread, PERF_R <<
55 33
56 if (al->map) 34 if (al->map)
57 dso = map__dso(al->map); !! 35 dso = al->map->dso;
58 36
59 if (!dso) 37 if (!dso)
60 return 0; 38 return 0;
61 39
62 /* <<
63 * The generated JIT DSO files only ma <<
64 * ELF headers. Since JIT codes used <<
65 * segment, calculating the base addre <<
66 * a different code in another DSO. S <<
67 * directly to pick the correct one. <<
68 */ <<
69 if (!strncmp(dso__long_name(dso), "/tm <<
70 base = map__start(al->map); <<
71 else <<
72 base = map__start(al->map) - m <<
73 <<
74 mod = dwfl_addrmodule(ui->dwfl, ip); 40 mod = dwfl_addrmodule(ui->dwfl, ip);
75 if (mod) { 41 if (mod) {
76 Dwarf_Addr s; 42 Dwarf_Addr s;
77 43
78 dwfl_module_info(mod, NULL, &s 44 dwfl_module_info(mod, NULL, &s, NULL, NULL, NULL, NULL, NULL);
79 if (s != base) !! 45 if (s != al->map->start - al->map->pgoff)
80 mod = NULL; !! 46 mod = 0;
81 } 47 }
82 48
83 if (!mod) { !! 49 if (!mod)
84 char filename[PATH_MAX]; !! 50 mod = dwfl_report_elf(ui->dwfl, dso->short_name,
85 !! 51 (dso->symsrc_filename ? dso->symsrc_filename : dso->long_name), -1, al->map->start - al->map->pgoff,
86 __symbol__join_symfs(filename, !! 52 false);
87 mod = dwfl_report_elf(ui->dwfl <<
88 base, fa <<
89 } <<
90 if (!mod) { <<
91 char filename[PATH_MAX]; <<
92 <<
93 if (dso__build_id_filename(dso <<
94 mod = dwfl_report_elf( <<
95 <<
96 } <<
97 <<
98 if (mod) { <<
99 void **userdatap; <<
100 <<
101 dwfl_module_info(mod, &userdat <<
102 *userdatap = dso; <<
103 } <<
104 53
105 return mod && dwfl_addrmodule(ui->dwfl 54 return mod && dwfl_addrmodule(ui->dwfl, ip) == mod ? 0 : -1;
106 } 55 }
107 56
108 static int report_module(u64 ip, struct unwind 57 static int report_module(u64 ip, struct unwind_info *ui)
109 { 58 {
110 struct addr_location al; 59 struct addr_location al;
111 int res; <<
112 60
113 addr_location__init(&al); !! 61 return __report_module(&al, ip, ui);
114 res = __report_module(&al, ip, ui); <<
115 addr_location__exit(&al); <<
116 return res; <<
117 } 62 }
118 63
119 /* 64 /*
120 * Store all entries within entries array, 65 * Store all entries within entries array,
121 * we will process it after we finish unwind. 66 * we will process it after we finish unwind.
122 */ 67 */
123 static int entry(u64 ip, struct unwind_info *u 68 static int entry(u64 ip, struct unwind_info *ui)
124 69
125 { 70 {
126 struct unwind_entry *e = &ui->entries[ 71 struct unwind_entry *e = &ui->entries[ui->idx++];
127 struct addr_location al; 72 struct addr_location al;
128 73
129 addr_location__init(&al); !! 74 if (__report_module(&al, ip, ui))
130 if (__report_module(&al, ip, ui)) { <<
131 addr_location__exit(&al); <<
132 return -1; 75 return -1;
133 } <<
134 76
135 e->ip = ip; !! 77 e->ip = al.addr;
136 e->ms.maps = al.maps; !! 78 e->map = al.map;
137 e->ms.map = al.map; !! 79 e->sym = al.sym;
138 e->ms.sym = al.sym; <<
139 80
140 pr_debug("unwind: %s:ip = 0x%" PRIx64 81 pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
141 al.sym ? al.sym->name : "''", 82 al.sym ? al.sym->name : "''",
142 ip, 83 ip,
143 al.map ? map__map_ip(al.map, !! 84 al.map ? al.map->map_ip(al.map, ip) : (u64) 0);
144 addr_location__exit(&al); <<
145 return 0; 85 return 0;
146 } 86 }
147 87
148 static pid_t next_thread(Dwfl *dwfl, void *arg 88 static pid_t next_thread(Dwfl *dwfl, void *arg, void **thread_argp)
149 { 89 {
150 /* We want only single thread to be pr 90 /* We want only single thread to be processed. */
151 if (*thread_argp != NULL) 91 if (*thread_argp != NULL)
152 return 0; 92 return 0;
153 93
154 *thread_argp = arg; 94 *thread_argp = arg;
155 return dwfl_pid(dwfl); 95 return dwfl_pid(dwfl);
156 } 96 }
157 97
158 static int access_dso_mem(struct unwind_info * 98 static int access_dso_mem(struct unwind_info *ui, Dwarf_Addr addr,
159 Dwarf_Word *data) 99 Dwarf_Word *data)
160 { 100 {
161 struct addr_location al; 101 struct addr_location al;
162 ssize_t size; 102 ssize_t size;
163 struct dso *dso; <<
164 103
165 addr_location__init(&al); !! 104 thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
166 if (!thread__find_map(ui->thread, PERF !! 105 MAP__FUNCTION, addr, &al);
>> 106 if (!al.map) {
>> 107 /*
>> 108 * We've seen cases (softice) where DWARF unwinder went
>> 109 * through non executable mmaps, which we need to lookup
>> 110 * in MAP__VARIABLE tree.
>> 111 */
>> 112 thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
>> 113 MAP__VARIABLE, addr, &al);
>> 114 }
>> 115
>> 116 if (!al.map) {
167 pr_debug("unwind: no map for % 117 pr_debug("unwind: no map for %lx\n", (unsigned long)addr);
168 goto out_fail; !! 118 return -1;
169 } 119 }
170 dso = map__dso(al.map); <<
171 if (!dso) <<
172 goto out_fail; <<
173 120
174 size = dso__data_read_addr(dso, al.map !! 121 if (!al.map->dso)
>> 122 return -1;
>> 123
>> 124 size = dso__data_read_addr(al.map->dso, al.map, ui->machine,
>> 125 addr, (u8 *) data, sizeof(*data));
175 126
176 addr_location__exit(&al); <<
177 return !(size == sizeof(*data)); 127 return !(size == sizeof(*data));
178 out_fail: <<
179 addr_location__exit(&al); <<
180 return -1; <<
181 } 128 }
182 129
183 static bool memory_read(Dwfl *dwfl __maybe_unu 130 static bool memory_read(Dwfl *dwfl __maybe_unused, Dwarf_Addr addr, Dwarf_Word *result,
184 void *arg) 131 void *arg)
185 { 132 {
186 struct unwind_info *ui = arg; 133 struct unwind_info *ui = arg;
187 const char *arch = perf_env__arch(ui-> <<
188 struct stack_dump *stack = &ui->sample 134 struct stack_dump *stack = &ui->sample->user_stack;
189 u64 start, end; 135 u64 start, end;
190 int offset; 136 int offset;
191 int ret; 137 int ret;
192 138
193 ret = perf_reg_value(&start, &ui->samp !! 139 ret = perf_reg_value(&start, &ui->sample->user_regs, PERF_REG_SP);
194 perf_arch_reg_sp( <<
195 if (ret) 140 if (ret)
196 return false; 141 return false;
197 142
198 end = start + stack->size; 143 end = start + stack->size;
199 144
200 /* Check overflow. */ 145 /* Check overflow. */
201 if (addr + sizeof(Dwarf_Word) < addr) 146 if (addr + sizeof(Dwarf_Word) < addr)
202 return false; 147 return false;
203 148
204 if (addr < start || addr + sizeof(Dwar 149 if (addr < start || addr + sizeof(Dwarf_Word) > end) {
205 ret = access_dso_mem(ui, addr, 150 ret = access_dso_mem(ui, addr, result);
206 if (ret) { 151 if (ret) {
207 pr_debug("unwind: acce 152 pr_debug("unwind: access_mem 0x%" PRIx64 " not inside range"
208 " 0x%" PRIx64 153 " 0x%" PRIx64 "-0x%" PRIx64 "\n",
209 addr, start, e 154 addr, start, end);
210 return false; 155 return false;
211 } 156 }
212 return true; 157 return true;
213 } 158 }
214 159
215 offset = addr - start; 160 offset = addr - start;
216 *result = *(Dwarf_Word *)&stack->data[ 161 *result = *(Dwarf_Word *)&stack->data[offset];
217 pr_debug("unwind: access_mem addr 0x%" 162 pr_debug("unwind: access_mem addr 0x%" PRIx64 ", val %lx, offset %d\n",
218 addr, (unsigned long)*result, 163 addr, (unsigned long)*result, offset);
219 return true; 164 return true;
220 } 165 }
221 166
222 static const Dwfl_Thread_Callbacks callbacks = 167 static const Dwfl_Thread_Callbacks callbacks = {
223 .next_thread = next_thread, 168 .next_thread = next_thread,
224 .memory_read = memory_read, 169 .memory_read = memory_read,
225 .set_initial_registers = libdw__arch_ 170 .set_initial_registers = libdw__arch_set_initial_registers,
226 }; 171 };
227 172
228 static int 173 static int
229 frame_callback(Dwfl_Frame *state, void *arg) 174 frame_callback(Dwfl_Frame *state, void *arg)
230 { 175 {
231 struct unwind_info *ui = arg; 176 struct unwind_info *ui = arg;
232 Dwarf_Addr pc; 177 Dwarf_Addr pc;
233 bool isactivation; 178 bool isactivation;
234 179
235 if (!dwfl_frame_pc(state, &pc, NULL)) <<
236 if (!ui->best_effort) <<
237 pr_err("%s", dwfl_errm <<
238 return DWARF_CB_ABORT; <<
239 } <<
240 <<
241 // report the module before we query f <<
242 report_module(pc, ui); <<
243 <<
244 if (!dwfl_frame_pc(state, &pc, &isacti 180 if (!dwfl_frame_pc(state, &pc, &isactivation)) {
245 if (!ui->best_effort) !! 181 pr_err("%s", dwfl_errmsg(-1));
246 pr_err("%s", dwfl_errm <<
247 return DWARF_CB_ABORT; 182 return DWARF_CB_ABORT;
248 } 183 }
249 184
250 if (!isactivation) 185 if (!isactivation)
251 --pc; 186 --pc;
252 187
253 return entry(pc, ui) || !(--ui->max_st 188 return entry(pc, ui) || !(--ui->max_stack) ?
254 DWARF_CB_ABORT : DWARF_CB_OK; 189 DWARF_CB_ABORT : DWARF_CB_OK;
255 } 190 }
256 191
257 int unwind__get_entries(unwind_entry_cb_t cb, 192 int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
258 struct thread *thread, 193 struct thread *thread,
259 struct perf_sample *da 194 struct perf_sample *data,
260 int max_stack, !! 195 int max_stack)
261 bool best_effort) <<
262 { 196 {
263 struct unwind_info *ui, ui_buf = { 197 struct unwind_info *ui, ui_buf = {
264 .sample = data, 198 .sample = data,
265 .thread = thread, 199 .thread = thread,
266 .machine = maps__machin !! 200 .machine = thread->mg->machine,
267 .cb = cb, 201 .cb = cb,
268 .arg = arg, 202 .arg = arg,
269 .max_stack = max_stack, 203 .max_stack = max_stack,
270 .best_effort = best_effort <<
271 }; 204 };
272 const char *arch = perf_env__arch(ui_b <<
273 Dwarf_Word ip; 205 Dwarf_Word ip;
274 int err = -EINVAL, i; 206 int err = -EINVAL, i;
275 207
276 if (!data->user_regs.regs) 208 if (!data->user_regs.regs)
277 return -EINVAL; 209 return -EINVAL;
278 210
279 ui = zalloc(sizeof(ui_buf) + sizeof(ui 211 ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack);
280 if (!ui) 212 if (!ui)
281 return -ENOMEM; 213 return -ENOMEM;
282 214
283 *ui = ui_buf; 215 *ui = ui_buf;
284 216
285 ui->dwfl = dwfl_begin(&offline_callbac 217 ui->dwfl = dwfl_begin(&offline_callbacks);
286 if (!ui->dwfl) 218 if (!ui->dwfl)
287 goto out; 219 goto out;
288 220
289 err = perf_reg_value(&ip, &data->user_ !! 221 err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
290 if (err) 222 if (err)
291 goto out; 223 goto out;
292 224
293 err = report_module(ip, ui); 225 err = report_module(ip, ui);
294 if (err) 226 if (err)
295 goto out; 227 goto out;
296 228
297 err = !dwfl_attach_state(ui->dwfl, EM_ !! 229 if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui))
298 if (err) <<
299 goto out; 230 goto out;
300 231
301 err = dwfl_getthread_frames(ui->dwfl, !! 232 err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui);
302 233
303 if (err && ui->max_stack != max_stack) 234 if (err && ui->max_stack != max_stack)
304 err = 0; 235 err = 0;
305 236
306 /* 237 /*
307 * Display what we got based on the or 238 * Display what we got based on the order setup.
308 */ 239 */
309 for (i = 0; i < ui->idx && !err; i++) 240 for (i = 0; i < ui->idx && !err; i++) {
310 int j = i; 241 int j = i;
311 242
312 if (callchain_param.order == O 243 if (callchain_param.order == ORDER_CALLER)
313 j = ui->idx - i - 1; 244 j = ui->idx - i - 1;
314 245
315 err = ui->entries[j].ip ? ui-> 246 err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0;
316 } 247 }
317 248
318 out: 249 out:
319 if (err) 250 if (err)
320 pr_debug("unwind: failed with 251 pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1));
321 252
322 dwfl_end(ui->dwfl); 253 dwfl_end(ui->dwfl);
323 free(ui); 254 free(ui);
324 return 0; 255 return 0;
325 } 256 }
326 257
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