1 // SPDX-License-Identifier: GPL-2.0
10 #include <linux/kernel.h>
17 #include "linux/string.h"
21 * Include definition of find_vdso_map() also used in perf-read-vdso.c for
22 * building perf-read-vdso32 and perf-read-vdsox32.
24 #include "find-vdso-map.c"
26 #define VDSO__TEMP_FILE_NAME "/tmp/perf-vdso.so-XXXXXX"
31 char temp_file_name[sizeof(VDSO__TEMP_FILE_NAME)];
33 const char *read_prog;
37 struct vdso_file vdso;
38 #if BITS_PER_LONG == 64
39 struct vdso_file vdso32;
40 struct vdso_file vdsox32;
44 static struct vdso_info *vdso_info__new(void)
46 static const struct vdso_info vdso_info_init = {
48 .temp_file_name = VDSO__TEMP_FILE_NAME,
49 .dso_name = DSO__NAME_VDSO,
51 #if BITS_PER_LONG == 64
53 .temp_file_name = VDSO__TEMP_FILE_NAME,
54 .dso_name = DSO__NAME_VDSO32,
55 .read_prog = "perf-read-vdso32",
58 .temp_file_name = VDSO__TEMP_FILE_NAME,
59 .dso_name = DSO__NAME_VDSOX32,
60 .read_prog = "perf-read-vdsox32",
65 return memdup(&vdso_info_init, sizeof(vdso_info_init));
68 static char *get_file(struct vdso_file *vdso_file)
77 return vdso_file->temp_file_name;
79 if (vdso_file->error || find_vdso_map(&start, &end))
84 buf = memdup(start, size);
88 fd = mkstemp(vdso_file->temp_file_name);
92 if (size == (size_t) write(fd, buf, size))
93 vdso = vdso_file->temp_file_name;
100 vdso_file->found = (vdso != NULL);
101 vdso_file->error = !vdso_file->found;
105 void machine__exit_vdso(struct machine *machine)
107 struct vdso_info *vdso_info = machine->vdso_info;
112 if (vdso_info->vdso.found)
113 unlink(vdso_info->vdso.temp_file_name);
114 #if BITS_PER_LONG == 64
115 if (vdso_info->vdso32.found)
116 unlink(vdso_info->vdso32.temp_file_name);
117 if (vdso_info->vdsox32.found)
118 unlink(vdso_info->vdsox32.temp_file_name);
121 zfree(&machine->vdso_info);
124 static struct dso *__machine__addnew_vdso(struct machine *machine, const char *short_name,
125 const char *long_name)
129 dso = dso__new(short_name);
131 __dsos__add(&machine->dsos, dso);
132 dso__set_long_name(dso, long_name, false);
138 static enum dso_type machine__thread_dso_type(struct machine *machine,
139 struct thread *thread)
141 enum dso_type dso_type = DSO__TYPE_UNKNOWN;
145 map = map_groups__first(thread->mg, MAP__FUNCTION);
146 for (; map ; map = map_groups__next(map)) {
148 if (!dso || dso->long_name[0] != '/')
150 dso_type = dso__type(dso, machine);
151 if (dso_type != DSO__TYPE_UNKNOWN)
158 #if BITS_PER_LONG == 64
160 static int vdso__do_copy_compat(FILE *f, int fd)
166 count = fread(buf, 1, sizeof(buf), f);
171 if (count && writen(fd, buf, count) != (ssize_t)count)
178 static int vdso__copy_compat(const char *prog, int fd)
183 f = popen(prog, "r");
187 err = vdso__do_copy_compat(f, fd);
195 static int vdso__create_compat_file(const char *prog, char *temp_name)
199 fd = mkstemp(temp_name);
203 err = vdso__copy_compat(prog, fd);
211 static const char *vdso__get_compat_file(struct vdso_file *vdso_file)
215 if (vdso_file->found)
216 return vdso_file->temp_file_name;
218 if (vdso_file->error)
221 err = vdso__create_compat_file(vdso_file->read_prog,
222 vdso_file->temp_file_name);
224 pr_err("%s failed, error %d\n", vdso_file->read_prog, err);
225 vdso_file->error = true;
229 vdso_file->found = true;
231 return vdso_file->temp_file_name;
234 static struct dso *__machine__findnew_compat(struct machine *machine,
235 struct vdso_file *vdso_file)
237 const char *file_name;
240 dso = __dsos__find(&machine->dsos, vdso_file->dso_name, true);
244 file_name = vdso__get_compat_file(vdso_file);
248 dso = __machine__addnew_vdso(machine, vdso_file->dso_name, file_name);
253 static int __machine__findnew_vdso_compat(struct machine *machine,
254 struct thread *thread,
255 struct vdso_info *vdso_info,
258 enum dso_type dso_type;
260 dso_type = machine__thread_dso_type(machine, thread);
262 #ifndef HAVE_PERF_READ_VDSO32
263 if (dso_type == DSO__TYPE_32BIT)
266 #ifndef HAVE_PERF_READ_VDSOX32
267 if (dso_type == DSO__TYPE_X32BIT)
272 case DSO__TYPE_32BIT:
273 *dso = __machine__findnew_compat(machine, &vdso_info->vdso32);
275 case DSO__TYPE_X32BIT:
276 *dso = __machine__findnew_compat(machine, &vdso_info->vdsox32);
278 case DSO__TYPE_UNKNOWN:
279 case DSO__TYPE_64BIT:
287 static struct dso *machine__find_vdso(struct machine *machine,
288 struct thread *thread)
290 struct dso *dso = NULL;
291 enum dso_type dso_type;
293 dso_type = machine__thread_dso_type(machine, thread);
295 case DSO__TYPE_32BIT:
296 dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO32, true);
298 dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO,
300 if (dso && dso_type != dso__type(dso, machine))
304 case DSO__TYPE_X32BIT:
305 dso = __dsos__find(&machine->dsos, DSO__NAME_VDSOX32, true);
307 case DSO__TYPE_64BIT:
308 case DSO__TYPE_UNKNOWN:
310 dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO, true);
317 struct dso *machine__findnew_vdso(struct machine *machine,
318 struct thread *thread)
320 struct vdso_info *vdso_info;
321 struct dso *dso = NULL;
323 pthread_rwlock_wrlock(&machine->dsos.lock);
324 if (!machine->vdso_info)
325 machine->vdso_info = vdso_info__new();
327 vdso_info = machine->vdso_info;
331 dso = machine__find_vdso(machine, thread);
335 #if BITS_PER_LONG == 64
336 if (__machine__findnew_vdso_compat(machine, thread, vdso_info, &dso))
340 dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO, true);
344 file = get_file(&vdso_info->vdso);
346 dso = __machine__addnew_vdso(machine, DSO__NAME_VDSO, file);
351 pthread_rwlock_unlock(&machine->dsos.lock);
355 bool dso__is_vdso(struct dso *dso)
357 return !strcmp(dso->short_name, DSO__NAME_VDSO) ||
358 !strcmp(dso->short_name, DSO__NAME_VDSO32) ||
359 !strcmp(dso->short_name, DSO__NAME_VDSOX32);