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v4.6
  1
  2#include <unistd.h>
  3#include <stdio.h>
  4#include <string.h>
  5#include <sys/types.h>
  6#include <sys/stat.h>
  7#include <fcntl.h>
  8#include <stdlib.h>
  9#include <linux/kernel.h>
 10
 11#include "vdso.h"
 12#include "util.h"
 13#include "symbol.h"
 14#include "machine.h"
 15#include "thread.h"
 16#include "linux/string.h"
 17#include "debug.h"
 18
 19/*
 20 * Include definition of find_vdso_map() also used in perf-read-vdso.c for
 21 * building perf-read-vdso32 and perf-read-vdsox32.
 22 */
 23#include "find-vdso-map.c"
 24
 25#define VDSO__TEMP_FILE_NAME "/tmp/perf-vdso.so-XXXXXX"
 26
 27struct vdso_file {
 28	bool found;
 29	bool error;
 30	char temp_file_name[sizeof(VDSO__TEMP_FILE_NAME)];
 31	const char *dso_name;
 32	const char *read_prog;
 33};
 34
 35struct vdso_info {
 36	struct vdso_file vdso;
 37#if BITS_PER_LONG == 64
 38	struct vdso_file vdso32;
 39	struct vdso_file vdsox32;
 40#endif
 41};
 42
 43static struct vdso_info *vdso_info__new(void)
 44{
 45	static const struct vdso_info vdso_info_init = {
 46		.vdso    = {
 47			.temp_file_name = VDSO__TEMP_FILE_NAME,
 48			.dso_name = DSO__NAME_VDSO,
 49		},
 50#if BITS_PER_LONG == 64
 51		.vdso32  = {
 52			.temp_file_name = VDSO__TEMP_FILE_NAME,
 53			.dso_name = DSO__NAME_VDSO32,
 54			.read_prog = "perf-read-vdso32",
 55		},
 56		.vdsox32  = {
 57			.temp_file_name = VDSO__TEMP_FILE_NAME,
 58			.dso_name = DSO__NAME_VDSOX32,
 59			.read_prog = "perf-read-vdsox32",
 60		},
 61#endif
 62	};
 63
 64	return memdup(&vdso_info_init, sizeof(vdso_info_init));
 65}
 66
 67static char *get_file(struct vdso_file *vdso_file)
 68{
 69	char *vdso = NULL;
 70	char *buf = NULL;
 71	void *start, *end;
 72	size_t size;
 73	int fd;
 74
 75	if (vdso_file->found)
 76		return vdso_file->temp_file_name;
 77
 78	if (vdso_file->error || find_vdso_map(&start, &end))
 79		return NULL;
 80
 81	size = end - start;
 82
 83	buf = memdup(start, size);
 84	if (!buf)
 85		return NULL;
 86
 87	fd = mkstemp(vdso_file->temp_file_name);
 88	if (fd < 0)
 89		goto out;
 90
 91	if (size == (size_t) write(fd, buf, size))
 92		vdso = vdso_file->temp_file_name;
 93
 94	close(fd);
 95
 96 out:
 97	free(buf);
 98
 99	vdso_file->found = (vdso != NULL);
100	vdso_file->error = !vdso_file->found;
101	return vdso;
102}
103
104void machine__exit_vdso(struct machine *machine)
105{
106	struct vdso_info *vdso_info = machine->vdso_info;
107
108	if (!vdso_info)
109		return;
110
111	if (vdso_info->vdso.found)
112		unlink(vdso_info->vdso.temp_file_name);
113#if BITS_PER_LONG == 64
114	if (vdso_info->vdso32.found)
115		unlink(vdso_info->vdso32.temp_file_name);
116	if (vdso_info->vdsox32.found)
117		unlink(vdso_info->vdsox32.temp_file_name);
118#endif
119
120	zfree(&machine->vdso_info);
121}
122
123static struct dso *__machine__addnew_vdso(struct machine *machine, const char *short_name,
124					  const char *long_name)
125{
126	struct dso *dso;
127
128	dso = dso__new(short_name);
129	if (dso != NULL) {
130		__dsos__add(&machine->dsos, dso);
131		dso__set_long_name(dso, long_name, false);
132	}
133
134	return dso;
135}
136
137#if BITS_PER_LONG == 64
138
139static enum dso_type machine__thread_dso_type(struct machine *machine,
140					      struct thread *thread)
141{
142	enum dso_type dso_type = DSO__TYPE_UNKNOWN;
143	struct map *map;
144	struct dso *dso;
145
146	map = map_groups__first(thread->mg, MAP__FUNCTION);
147	for (; map ; map = map_groups__next(map)) {
148		dso = map->dso;
149		if (!dso || dso->long_name[0] != '/')
150			continue;
151		dso_type = dso__type(dso, machine);
152		if (dso_type != DSO__TYPE_UNKNOWN)
153			break;
154	}
155
156	return dso_type;
157}
158
 
 
159static int vdso__do_copy_compat(FILE *f, int fd)
160{
161	char buf[4096];
162	size_t count;
163
164	while (1) {
165		count = fread(buf, 1, sizeof(buf), f);
166		if (ferror(f))
167			return -errno;
168		if (feof(f))
169			break;
170		if (count && writen(fd, buf, count) != (ssize_t)count)
171			return -errno;
172	}
173
174	return 0;
175}
176
177static int vdso__copy_compat(const char *prog, int fd)
178{
179	FILE *f;
180	int err;
181
182	f = popen(prog, "r");
183	if (!f)
184		return -errno;
185
186	err = vdso__do_copy_compat(f, fd);
187
188	if (pclose(f) == -1)
189		return -errno;
190
191	return err;
192}
193
194static int vdso__create_compat_file(const char *prog, char *temp_name)
195{
196	int fd, err;
197
198	fd = mkstemp(temp_name);
199	if (fd < 0)
200		return -errno;
201
202	err = vdso__copy_compat(prog, fd);
203
204	if (close(fd) == -1)
205		return -errno;
206
207	return err;
208}
209
210static const char *vdso__get_compat_file(struct vdso_file *vdso_file)
211{
212	int err;
213
214	if (vdso_file->found)
215		return vdso_file->temp_file_name;
216
217	if (vdso_file->error)
218		return NULL;
219
220	err = vdso__create_compat_file(vdso_file->read_prog,
221				       vdso_file->temp_file_name);
222	if (err) {
223		pr_err("%s failed, error %d\n", vdso_file->read_prog, err);
224		vdso_file->error = true;
225		return NULL;
226	}
227
228	vdso_file->found = true;
229
230	return vdso_file->temp_file_name;
231}
232
233static struct dso *__machine__findnew_compat(struct machine *machine,
234					     struct vdso_file *vdso_file)
235{
236	const char *file_name;
237	struct dso *dso;
238
239	dso = __dsos__find(&machine->dsos, vdso_file->dso_name, true);
240	if (dso)
241		goto out;
242
243	file_name = vdso__get_compat_file(vdso_file);
244	if (!file_name)
245		goto out;
246
247	dso = __machine__addnew_vdso(machine, vdso_file->dso_name, file_name);
248out:
249	return dso;
250}
251
252static int __machine__findnew_vdso_compat(struct machine *machine,
253					  struct thread *thread,
254					  struct vdso_info *vdso_info,
255					  struct dso **dso)
256{
257	enum dso_type dso_type;
258
259	dso_type = machine__thread_dso_type(machine, thread);
260
261#ifndef HAVE_PERF_READ_VDSO32
262	if (dso_type == DSO__TYPE_32BIT)
263		return 0;
264#endif
265#ifndef HAVE_PERF_READ_VDSOX32
266	if (dso_type == DSO__TYPE_X32BIT)
267		return 0;
268#endif
269
270	switch (dso_type) {
271	case DSO__TYPE_32BIT:
272		*dso = __machine__findnew_compat(machine, &vdso_info->vdso32);
273		return 1;
274	case DSO__TYPE_X32BIT:
275		*dso = __machine__findnew_compat(machine, &vdso_info->vdsox32);
276		return 1;
277	case DSO__TYPE_UNKNOWN:
278	case DSO__TYPE_64BIT:
279	default:
280		return 0;
281	}
282}
283
284#endif
285
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
286struct dso *machine__findnew_vdso(struct machine *machine,
287				  struct thread *thread __maybe_unused)
288{
289	struct vdso_info *vdso_info;
290	struct dso *dso = NULL;
291
292	pthread_rwlock_wrlock(&machine->dsos.lock);
293	if (!machine->vdso_info)
294		machine->vdso_info = vdso_info__new();
295
296	vdso_info = machine->vdso_info;
297	if (!vdso_info)
 
 
 
 
298		goto out_unlock;
299
300#if BITS_PER_LONG == 64
301	if (__machine__findnew_vdso_compat(machine, thread, vdso_info, &dso))
302		goto out_unlock;
303#endif
304
305	dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO, true);
306	if (!dso) {
307		char *file;
308
309		file = get_file(&vdso_info->vdso);
310		if (file)
311			dso = __machine__addnew_vdso(machine, DSO__NAME_VDSO, file);
312	}
313
314out_unlock:
315	dso__get(dso);
316	pthread_rwlock_unlock(&machine->dsos.lock);
317	return dso;
318}
319
320bool dso__is_vdso(struct dso *dso)
321{
322	return !strcmp(dso->short_name, DSO__NAME_VDSO) ||
323	       !strcmp(dso->short_name, DSO__NAME_VDSO32) ||
324	       !strcmp(dso->short_name, DSO__NAME_VDSOX32);
325}
v4.10.11
  1
  2#include <unistd.h>
  3#include <stdio.h>
  4#include <string.h>
  5#include <sys/types.h>
  6#include <sys/stat.h>
  7#include <fcntl.h>
  8#include <stdlib.h>
  9#include <linux/kernel.h>
 10
 11#include "vdso.h"
 12#include "util.h"
 13#include "symbol.h"
 14#include "machine.h"
 15#include "thread.h"
 16#include "linux/string.h"
 17#include "debug.h"
 18
 19/*
 20 * Include definition of find_vdso_map() also used in perf-read-vdso.c for
 21 * building perf-read-vdso32 and perf-read-vdsox32.
 22 */
 23#include "find-vdso-map.c"
 24
 25#define VDSO__TEMP_FILE_NAME "/tmp/perf-vdso.so-XXXXXX"
 26
 27struct vdso_file {
 28	bool found;
 29	bool error;
 30	char temp_file_name[sizeof(VDSO__TEMP_FILE_NAME)];
 31	const char *dso_name;
 32	const char *read_prog;
 33};
 34
 35struct vdso_info {
 36	struct vdso_file vdso;
 37#if BITS_PER_LONG == 64
 38	struct vdso_file vdso32;
 39	struct vdso_file vdsox32;
 40#endif
 41};
 42
 43static struct vdso_info *vdso_info__new(void)
 44{
 45	static const struct vdso_info vdso_info_init = {
 46		.vdso    = {
 47			.temp_file_name = VDSO__TEMP_FILE_NAME,
 48			.dso_name = DSO__NAME_VDSO,
 49		},
 50#if BITS_PER_LONG == 64
 51		.vdso32  = {
 52			.temp_file_name = VDSO__TEMP_FILE_NAME,
 53			.dso_name = DSO__NAME_VDSO32,
 54			.read_prog = "perf-read-vdso32",
 55		},
 56		.vdsox32  = {
 57			.temp_file_name = VDSO__TEMP_FILE_NAME,
 58			.dso_name = DSO__NAME_VDSOX32,
 59			.read_prog = "perf-read-vdsox32",
 60		},
 61#endif
 62	};
 63
 64	return memdup(&vdso_info_init, sizeof(vdso_info_init));
 65}
 66
 67static char *get_file(struct vdso_file *vdso_file)
 68{
 69	char *vdso = NULL;
 70	char *buf = NULL;
 71	void *start, *end;
 72	size_t size;
 73	int fd;
 74
 75	if (vdso_file->found)
 76		return vdso_file->temp_file_name;
 77
 78	if (vdso_file->error || find_vdso_map(&start, &end))
 79		return NULL;
 80
 81	size = end - start;
 82
 83	buf = memdup(start, size);
 84	if (!buf)
 85		return NULL;
 86
 87	fd = mkstemp(vdso_file->temp_file_name);
 88	if (fd < 0)
 89		goto out;
 90
 91	if (size == (size_t) write(fd, buf, size))
 92		vdso = vdso_file->temp_file_name;
 93
 94	close(fd);
 95
 96 out:
 97	free(buf);
 98
 99	vdso_file->found = (vdso != NULL);
100	vdso_file->error = !vdso_file->found;
101	return vdso;
102}
103
104void machine__exit_vdso(struct machine *machine)
105{
106	struct vdso_info *vdso_info = machine->vdso_info;
107
108	if (!vdso_info)
109		return;
110
111	if (vdso_info->vdso.found)
112		unlink(vdso_info->vdso.temp_file_name);
113#if BITS_PER_LONG == 64
114	if (vdso_info->vdso32.found)
115		unlink(vdso_info->vdso32.temp_file_name);
116	if (vdso_info->vdsox32.found)
117		unlink(vdso_info->vdsox32.temp_file_name);
118#endif
119
120	zfree(&machine->vdso_info);
121}
122
123static struct dso *__machine__addnew_vdso(struct machine *machine, const char *short_name,
124					  const char *long_name)
125{
126	struct dso *dso;
127
128	dso = dso__new(short_name);
129	if (dso != NULL) {
130		__dsos__add(&machine->dsos, dso);
131		dso__set_long_name(dso, long_name, false);
132	}
133
134	return dso;
135}
136
 
 
137static enum dso_type machine__thread_dso_type(struct machine *machine,
138					      struct thread *thread)
139{
140	enum dso_type dso_type = DSO__TYPE_UNKNOWN;
141	struct map *map;
142	struct dso *dso;
143
144	map = map_groups__first(thread->mg, MAP__FUNCTION);
145	for (; map ; map = map_groups__next(map)) {
146		dso = map->dso;
147		if (!dso || dso->long_name[0] != '/')
148			continue;
149		dso_type = dso__type(dso, machine);
150		if (dso_type != DSO__TYPE_UNKNOWN)
151			break;
152	}
153
154	return dso_type;
155}
156
157#if BITS_PER_LONG == 64
158
159static int vdso__do_copy_compat(FILE *f, int fd)
160{
161	char buf[4096];
162	size_t count;
163
164	while (1) {
165		count = fread(buf, 1, sizeof(buf), f);
166		if (ferror(f))
167			return -errno;
168		if (feof(f))
169			break;
170		if (count && writen(fd, buf, count) != (ssize_t)count)
171			return -errno;
172	}
173
174	return 0;
175}
176
177static int vdso__copy_compat(const char *prog, int fd)
178{
179	FILE *f;
180	int err;
181
182	f = popen(prog, "r");
183	if (!f)
184		return -errno;
185
186	err = vdso__do_copy_compat(f, fd);
187
188	if (pclose(f) == -1)
189		return -errno;
190
191	return err;
192}
193
194static int vdso__create_compat_file(const char *prog, char *temp_name)
195{
196	int fd, err;
197
198	fd = mkstemp(temp_name);
199	if (fd < 0)
200		return -errno;
201
202	err = vdso__copy_compat(prog, fd);
203
204	if (close(fd) == -1)
205		return -errno;
206
207	return err;
208}
209
210static const char *vdso__get_compat_file(struct vdso_file *vdso_file)
211{
212	int err;
213
214	if (vdso_file->found)
215		return vdso_file->temp_file_name;
216
217	if (vdso_file->error)
218		return NULL;
219
220	err = vdso__create_compat_file(vdso_file->read_prog,
221				       vdso_file->temp_file_name);
222	if (err) {
223		pr_err("%s failed, error %d\n", vdso_file->read_prog, err);
224		vdso_file->error = true;
225		return NULL;
226	}
227
228	vdso_file->found = true;
229
230	return vdso_file->temp_file_name;
231}
232
233static struct dso *__machine__findnew_compat(struct machine *machine,
234					     struct vdso_file *vdso_file)
235{
236	const char *file_name;
237	struct dso *dso;
238
239	dso = __dsos__find(&machine->dsos, vdso_file->dso_name, true);
240	if (dso)
241		goto out;
242
243	file_name = vdso__get_compat_file(vdso_file);
244	if (!file_name)
245		goto out;
246
247	dso = __machine__addnew_vdso(machine, vdso_file->dso_name, file_name);
248out:
249	return dso;
250}
251
252static int __machine__findnew_vdso_compat(struct machine *machine,
253					  struct thread *thread,
254					  struct vdso_info *vdso_info,
255					  struct dso **dso)
256{
257	enum dso_type dso_type;
258
259	dso_type = machine__thread_dso_type(machine, thread);
260
261#ifndef HAVE_PERF_READ_VDSO32
262	if (dso_type == DSO__TYPE_32BIT)
263		return 0;
264#endif
265#ifndef HAVE_PERF_READ_VDSOX32
266	if (dso_type == DSO__TYPE_X32BIT)
267		return 0;
268#endif
269
270	switch (dso_type) {
271	case DSO__TYPE_32BIT:
272		*dso = __machine__findnew_compat(machine, &vdso_info->vdso32);
273		return 1;
274	case DSO__TYPE_X32BIT:
275		*dso = __machine__findnew_compat(machine, &vdso_info->vdsox32);
276		return 1;
277	case DSO__TYPE_UNKNOWN:
278	case DSO__TYPE_64BIT:
279	default:
280		return 0;
281	}
282}
283
284#endif
285
286static struct dso *machine__find_vdso(struct machine *machine,
287				      struct thread *thread)
288{
289	struct dso *dso = NULL;
290	enum dso_type dso_type;
291
292	dso_type = machine__thread_dso_type(machine, thread);
293	switch (dso_type) {
294	case DSO__TYPE_32BIT:
295		dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO32, true);
296		if (!dso) {
297			dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO,
298					   true);
299			if (dso && dso_type != dso__type(dso, machine))
300				dso = NULL;
301		}
302		break;
303	case DSO__TYPE_X32BIT:
304		dso = __dsos__find(&machine->dsos, DSO__NAME_VDSOX32, true);
305		break;
306	case DSO__TYPE_64BIT:
307	case DSO__TYPE_UNKNOWN:
308	default:
309		dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO, true);
310		break;
311	}
312
313	return dso;
314}
315
316struct dso *machine__findnew_vdso(struct machine *machine,
317				  struct thread *thread)
318{
319	struct vdso_info *vdso_info;
320	struct dso *dso = NULL;
321
322	pthread_rwlock_wrlock(&machine->dsos.lock);
323	if (!machine->vdso_info)
324		machine->vdso_info = vdso_info__new();
325
326	vdso_info = machine->vdso_info;
327	if (!vdso_info)
328		goto out_unlock;
329
330	dso = machine__find_vdso(machine, thread);
331	if (dso)
332		goto out_unlock;
333
334#if BITS_PER_LONG == 64
335	if (__machine__findnew_vdso_compat(machine, thread, vdso_info, &dso))
336		goto out_unlock;
337#endif
338
339	dso = __dsos__find(&machine->dsos, DSO__NAME_VDSO, true);
340	if (!dso) {
341		char *file;
342
343		file = get_file(&vdso_info->vdso);
344		if (file)
345			dso = __machine__addnew_vdso(machine, DSO__NAME_VDSO, file);
346	}
347
348out_unlock:
349	dso__get(dso);
350	pthread_rwlock_unlock(&machine->dsos.lock);
351	return dso;
352}
353
354bool dso__is_vdso(struct dso *dso)
355{
356	return !strcmp(dso->short_name, DSO__NAME_VDSO) ||
357	       !strcmp(dso->short_name, DSO__NAME_VDSO32) ||
358	       !strcmp(dso->short_name, DSO__NAME_VDSOX32);
359}