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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2#include "../perf.h"
  3#include "util.h"
  4#include "debug.h"
  5#include <api/fs/fs.h>
  6#include <sys/mman.h>
  7#include <sys/stat.h>
  8#include <sys/utsname.h>
  9#include <dirent.h>
 10#include <fcntl.h>
 11#include <inttypes.h>
 12#include <signal.h>
 13#include <stdio.h>
 14#include <stdlib.h>
 15#include <string.h>
 16#include <errno.h>
 17#include <limits.h>
 
 18#include <linux/kernel.h>
 19#include <linux/log2.h>
 20#include <linux/time64.h>
 21#include <unistd.h>
 22#include "strlist.h"
 23
 24/*
 25 * XXX We need to find a better place for these things...
 26 */
 27
 28bool perf_singlethreaded = true;
 29
 30void perf_set_singlethreaded(void)
 31{
 32	perf_singlethreaded = true;
 33}
 34
 35void perf_set_multithreaded(void)
 36{
 37	perf_singlethreaded = false;
 38}
 39
 40unsigned int page_size;
 41int cacheline_size;
 42
 43int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
 44int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
 45
 46bool test_attr__enabled;
 47
 48bool perf_host  = true;
 49bool perf_guest = false;
 50
 
 
 51void event_attr_init(struct perf_event_attr *attr)
 52{
 53	if (!perf_host)
 54		attr->exclude_host  = 1;
 55	if (!perf_guest)
 56		attr->exclude_guest = 1;
 57	/* to capture ABI version */
 58	attr->size = sizeof(*attr);
 59}
 60
 61int mkdir_p(char *path, mode_t mode)
 62{
 63	struct stat st;
 64	int err;
 65	char *d = path;
 66
 67	if (*d != '/')
 68		return -1;
 69
 70	if (stat(path, &st) == 0)
 71		return 0;
 72
 73	while (*++d == '/');
 74
 75	while ((d = strchr(d, '/'))) {
 76		*d = '\0';
 77		err = stat(path, &st) && mkdir(path, mode);
 78		*d++ = '/';
 79		if (err)
 80			return -1;
 81		while (*d == '/')
 82			++d;
 83	}
 84	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
 85}
 86
 87int rm_rf(const char *path)
 88{
 89	DIR *dir;
 90	int ret = 0;
 91	struct dirent *d;
 92	char namebuf[PATH_MAX];
 93
 94	dir = opendir(path);
 95	if (dir == NULL)
 96		return 0;
 97
 98	while ((d = readdir(dir)) != NULL && !ret) {
 99		struct stat statbuf;
100
101		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
102			continue;
103
104		scnprintf(namebuf, sizeof(namebuf), "%s/%s",
105			  path, d->d_name);
106
107		/* We have to check symbolic link itself */
108		ret = lstat(namebuf, &statbuf);
109		if (ret < 0) {
110			pr_debug("stat failed: %s\n", namebuf);
111			break;
112		}
113
114		if (S_ISDIR(statbuf.st_mode))
115			ret = rm_rf(namebuf);
116		else
117			ret = unlink(namebuf);
118	}
119	closedir(dir);
120
121	if (ret < 0)
122		return ret;
123
124	return rmdir(path);
125}
126
127/* A filter which removes dot files */
128bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
129{
130	return d->d_name[0] != '.';
131}
132
133/* lsdir reads a directory and store it in strlist */
134struct strlist *lsdir(const char *name,
135		      bool (*filter)(const char *, struct dirent *))
136{
137	struct strlist *list = NULL;
138	DIR *dir;
139	struct dirent *d;
140
141	dir = opendir(name);
142	if (!dir)
143		return NULL;
144
145	list = strlist__new(NULL, NULL);
146	if (!list) {
147		errno = ENOMEM;
148		goto out;
149	}
150
151	while ((d = readdir(dir)) != NULL) {
152		if (!filter || filter(name, d))
153			strlist__add(list, d->d_name);
154	}
155
156out:
157	closedir(dir);
158	return list;
159}
160
161static int slow_copyfile(const char *from, const char *to, struct nsinfo *nsi)
162{
163	int err = -1;
164	char *line = NULL;
165	size_t n;
166	FILE *from_fp, *to_fp;
167	struct nscookie nsc;
168
169	nsinfo__mountns_enter(nsi, &nsc);
170	from_fp = fopen(from, "r");
171	nsinfo__mountns_exit(&nsc);
172	if (from_fp == NULL)
173		goto out;
174
 
175	to_fp = fopen(to, "w");
 
176	if (to_fp == NULL)
177		goto out_fclose_from;
178
179	while (getline(&line, &n, from_fp) > 0)
180		if (fputs(line, to_fp) == EOF)
181			goto out_fclose_to;
182	err = 0;
183out_fclose_to:
184	fclose(to_fp);
185	free(line);
186out_fclose_from:
187	fclose(from_fp);
188out:
189	return err;
190}
191
192static int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
193{
194	void *ptr;
195	loff_t pgoff;
196
197	pgoff = off_in & ~(page_size - 1);
198	off_in -= pgoff;
199
200	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
201	if (ptr == MAP_FAILED)
202		return -1;
203
204	while (size) {
205		ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
206		if (ret < 0 && errno == EINTR)
207			continue;
208		if (ret <= 0)
209			break;
210
211		size -= ret;
212		off_in += ret;
213		off_out += ret;
214	}
215	munmap(ptr, off_in + size);
216
217	return size ? -1 : 0;
218}
219
220static int copyfile_mode_ns(const char *from, const char *to, mode_t mode,
221			    struct nsinfo *nsi)
222{
223	int fromfd, tofd;
224	struct stat st;
225	int err;
226	char *tmp = NULL, *ptr = NULL;
227	struct nscookie nsc;
228
229	nsinfo__mountns_enter(nsi, &nsc);
230	err = stat(from, &st);
231	nsinfo__mountns_exit(&nsc);
232	if (err)
233		goto out;
234	err = -1;
235
236	/* extra 'x' at the end is to reserve space for '.' */
237	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
238		tmp = NULL;
239		goto out;
240	}
241	ptr = strrchr(tmp, '/');
242	if (!ptr)
243		goto out;
244	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
245	*ptr = '.';
246
247	tofd = mkstemp(tmp);
248	if (tofd < 0)
249		goto out;
250
251	if (fchmod(tofd, mode))
252		goto out_close_to;
253
254	if (st.st_size == 0) { /* /proc? do it slowly... */
255		err = slow_copyfile(from, tmp, nsi);
256		goto out_close_to;
257	}
258
259	nsinfo__mountns_enter(nsi, &nsc);
260	fromfd = open(from, O_RDONLY);
261	nsinfo__mountns_exit(&nsc);
262	if (fromfd < 0)
263		goto out_close_to;
264
265	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
 
266
267	close(fromfd);
268out_close_to:
269	close(tofd);
270	if (!err)
271		err = link(tmp, to);
272	unlink(tmp);
 
273out:
274	free(tmp);
275	return err;
276}
277
278int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi)
279{
280	return copyfile_mode_ns(from, to, 0755, nsi);
281}
282
283int copyfile_mode(const char *from, const char *to, mode_t mode)
284{
285	return copyfile_mode_ns(from, to, mode, NULL);
286}
287
288int copyfile(const char *from, const char *to)
289{
290	return copyfile_mode(from, to, 0755);
 
 
 
 
 
 
 
 
 
 
 
 
 
291}
292
293static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
294{
295	void *buf_start = buf;
296	size_t left = n;
297
298	while (left) {
299		/* buf must be treated as const if !is_read. */
300		ssize_t ret = is_read ? read(fd, buf, left) :
301					write(fd, buf, left);
302
303		if (ret < 0 && errno == EINTR)
304			continue;
305		if (ret <= 0)
306			return ret;
307
308		left -= ret;
309		buf  += ret;
310	}
311
312	BUG_ON((size_t)(buf - buf_start) != n);
313	return n;
314}
315
316/*
317 * Read exactly 'n' bytes or return an error.
318 */
319ssize_t readn(int fd, void *buf, size_t n)
320{
321	return ion(true, fd, buf, n);
322}
323
324/*
325 * Write exactly 'n' bytes or return an error.
326 */
327ssize_t writen(int fd, const void *buf, size_t n)
328{
329	/* ion does not modify buf. */
330	return ion(false, fd, (void *)buf, n);
331}
332
333size_t hex_width(u64 v)
334{
335	size_t n = 1;
336
337	while ((v >>= 4))
338		++n;
339
340	return n;
341}
342
 
 
 
 
 
 
 
 
 
 
 
343/*
344 * While we find nice hex chars, build a long_val.
345 * Return number of chars processed.
346 */
347int hex2u64(const char *ptr, u64 *long_val)
348{
349	char *p;
 
350
351	*long_val = strtoull(ptr, &p, 16);
 
 
 
 
 
 
 
 
352
353	return p - ptr;
354}
355
356int perf_event_paranoid(void)
 
 
357{
358	int value;
 
 
 
359
360	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
361		return INT_MAX;
362
363	return value;
 
 
 
364}
365static int
366fetch_ubuntu_kernel_version(unsigned int *puint)
367{
368	ssize_t len;
369	size_t line_len = 0;
370	char *ptr, *line = NULL;
371	int version, patchlevel, sublevel, err;
372	FILE *vsig;
373
374	if (!puint)
375		return 0;
 
376
377	vsig = fopen("/proc/version_signature", "r");
378	if (!vsig) {
379		pr_debug("Open /proc/version_signature failed: %s\n",
380			 strerror(errno));
381		return -1;
 
 
 
382	}
 
 
 
 
 
 
 
 
383
384	len = getline(&line, &line_len, vsig);
385	fclose(vsig);
386	err = -1;
387	if (len <= 0) {
388		pr_debug("Reading from /proc/version_signature failed: %s\n",
389			 strerror(errno));
390		goto errout;
391	}
392
393	ptr = strrchr(line, ' ');
394	if (!ptr) {
395		pr_debug("Parsing /proc/version_signature failed: %s\n", line);
396		goto errout;
397	}
398
399	err = sscanf(ptr + 1, "%d.%d.%d",
400		     &version, &patchlevel, &sublevel);
401	if (err != 3) {
402		pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
403			 line);
404		goto errout;
405	}
406
407	*puint = (version << 16) + (patchlevel << 8) + sublevel;
408	err = 0;
409errout:
410	free(line);
411	return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
412}
413
414int
415fetch_kernel_version(unsigned int *puint, char *str,
416		     size_t str_size)
417{
418	struct utsname utsname;
419	int version, patchlevel, sublevel, err;
420	bool int_ver_ready = false;
421
422	if (access("/proc/version_signature", R_OK) == 0)
423		if (!fetch_ubuntu_kernel_version(puint))
424			int_ver_ready = true;
425
426	if (uname(&utsname))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
427		return -1;
428
429	if (str && str_size) {
430		strncpy(str, utsname.release, str_size);
431		str[str_size - 1] = '\0';
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
432	}
433
434	if (!puint || int_ver_ready)
435		return 0;
436
437	err = sscanf(utsname.release, "%d.%d.%d",
438		     &version, &patchlevel, &sublevel);
 
 
439
440	if (err != 3) {
441		pr_debug("Unable to get kernel version from uname '%s'\n",
442			 utsname.release);
443		return -1;
 
 
 
 
444	}
445
446	*puint = (version << 16) + (patchlevel << 8) + sublevel;
447	return 0;
448}
449
450const char *perf_tip(const char *dirpath)
451{
452	struct strlist *tips;
453	struct str_node *node;
454	char *tip = NULL;
455	struct strlist_config conf = {
456		.dirname = dirpath,
457		.file_only = true,
458	};
459
460	tips = strlist__new("tips.txt", &conf);
461	if (tips == NULL)
462		return errno == ENOENT ? NULL :
463			"Tip: check path of tips.txt or get more memory! ;-p";
 
 
 
 
464
465	if (strlist__nr_entries(tips) == 0)
466		goto out;
467
468	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
469	if (asprintf(&tip, "Tip: %s", node->s) < 0)
470		tip = (char *)"Tip: get more memory! ;-)";
 
 
 
 
 
471
472out:
473	strlist__delete(tips);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
474
475	return tip;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
476}
v3.15
 
  1#include "../perf.h"
  2#include "util.h"
 
  3#include <api/fs/fs.h>
  4#include <sys/mman.h>
  5#ifdef HAVE_BACKTRACE_SUPPORT
  6#include <execinfo.h>
  7#endif
 
 
 
  8#include <stdio.h>
  9#include <stdlib.h>
 10#include <string.h>
 11#include <errno.h>
 12#include <limits.h>
 13#include <byteswap.h>
 14#include <linux/kernel.h>
 
 
 
 
 15
 16/*
 17 * XXX We need to find a better place for these things...
 18 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 19unsigned int page_size;
 
 
 
 
 20
 21bool test_attr__enabled;
 22
 23bool perf_host  = true;
 24bool perf_guest = false;
 25
 26char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
 27
 28void event_attr_init(struct perf_event_attr *attr)
 29{
 30	if (!perf_host)
 31		attr->exclude_host  = 1;
 32	if (!perf_guest)
 33		attr->exclude_guest = 1;
 34	/* to capture ABI version */
 35	attr->size = sizeof(*attr);
 36}
 37
 38int mkdir_p(char *path, mode_t mode)
 39{
 40	struct stat st;
 41	int err;
 42	char *d = path;
 43
 44	if (*d != '/')
 45		return -1;
 46
 47	if (stat(path, &st) == 0)
 48		return 0;
 49
 50	while (*++d == '/');
 51
 52	while ((d = strchr(d, '/'))) {
 53		*d = '\0';
 54		err = stat(path, &st) && mkdir(path, mode);
 55		*d++ = '/';
 56		if (err)
 57			return -1;
 58		while (*d == '/')
 59			++d;
 60	}
 61	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
 62}
 63
 64static int slow_copyfile(const char *from, const char *to, mode_t mode)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 65{
 66	int err = -1;
 67	char *line = NULL;
 68	size_t n;
 69	FILE *from_fp = fopen(from, "r"), *to_fp;
 70	mode_t old_umask;
 71
 
 
 
 72	if (from_fp == NULL)
 73		goto out;
 74
 75	old_umask = umask(mode ^ 0777);
 76	to_fp = fopen(to, "w");
 77	umask(old_umask);
 78	if (to_fp == NULL)
 79		goto out_fclose_from;
 80
 81	while (getline(&line, &n, from_fp) > 0)
 82		if (fputs(line, to_fp) == EOF)
 83			goto out_fclose_to;
 84	err = 0;
 85out_fclose_to:
 86	fclose(to_fp);
 87	free(line);
 88out_fclose_from:
 89	fclose(from_fp);
 90out:
 91	return err;
 92}
 93
 94int copyfile_mode(const char *from, const char *to, mode_t mode)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 95{
 96	int fromfd, tofd;
 97	struct stat st;
 98	void *addr;
 99	int err = -1;
 
100
101	if (stat(from, &st))
 
 
 
102		goto out;
 
103
104	if (st.st_size == 0) /* /proc? do it slowly... */
105		return slow_copyfile(from, to, mode);
 
 
 
 
 
 
 
 
106
107	fromfd = open(from, O_RDONLY);
108	if (fromfd < 0)
109		goto out;
110
111	tofd = creat(to, mode);
112	if (tofd < 0)
113		goto out_close_from;
 
 
 
 
114
115	addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fromfd, 0);
116	if (addr == MAP_FAILED)
 
 
117		goto out_close_to;
118
119	if (write(tofd, addr, st.st_size) == st.st_size)
120		err = 0;
121
122	munmap(addr, st.st_size);
123out_close_to:
124	close(tofd);
125	if (err)
126		unlink(to);
127out_close_from:
128	close(fromfd);
129out:
 
130	return err;
131}
132
133int copyfile(const char *from, const char *to)
134{
135	return copyfile_mode(from, to, 0755);
136}
137
138unsigned long convert_unit(unsigned long value, char *unit)
139{
140	*unit = ' ';
 
141
142	if (value > 1000) {
143		value /= 1000;
144		*unit = 'K';
145	}
146
147	if (value > 1000) {
148		value /= 1000;
149		*unit = 'M';
150	}
151
152	if (value > 1000) {
153		value /= 1000;
154		*unit = 'G';
155	}
156
157	return value;
158}
159
160static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
161{
162	void *buf_start = buf;
163	size_t left = n;
164
165	while (left) {
 
166		ssize_t ret = is_read ? read(fd, buf, left) :
167					write(fd, buf, left);
168
 
 
169		if (ret <= 0)
170			return ret;
171
172		left -= ret;
173		buf  += ret;
174	}
175
176	BUG_ON((size_t)(buf - buf_start) != n);
177	return n;
178}
179
180/*
181 * Read exactly 'n' bytes or return an error.
182 */
183ssize_t readn(int fd, void *buf, size_t n)
184{
185	return ion(true, fd, buf, n);
186}
187
188/*
189 * Write exactly 'n' bytes or return an error.
190 */
191ssize_t writen(int fd, void *buf, size_t n)
192{
193	return ion(false, fd, buf, n);
 
194}
195
196size_t hex_width(u64 v)
197{
198	size_t n = 1;
199
200	while ((v >>= 4))
201		++n;
202
203	return n;
204}
205
206static int hex(char ch)
207{
208	if ((ch >= '0') && (ch <= '9'))
209		return ch - '0';
210	if ((ch >= 'a') && (ch <= 'f'))
211		return ch - 'a' + 10;
212	if ((ch >= 'A') && (ch <= 'F'))
213		return ch - 'A' + 10;
214	return -1;
215}
216
217/*
218 * While we find nice hex chars, build a long_val.
219 * Return number of chars processed.
220 */
221int hex2u64(const char *ptr, u64 *long_val)
222{
223	const char *p = ptr;
224	*long_val = 0;
225
226	while (*p) {
227		const int hex_val = hex(*p);
228
229		if (hex_val < 0)
230			break;
231
232		*long_val = (*long_val << 4) | hex_val;
233		p++;
234	}
235
236	return p - ptr;
237}
238
239/* Obtain a backtrace and print it to stdout. */
240#ifdef HAVE_BACKTRACE_SUPPORT
241void dump_stack(void)
242{
243	void *array[16];
244	size_t size = backtrace(array, ARRAY_SIZE(array));
245	char **strings = backtrace_symbols(array, size);
246	size_t i;
247
248	printf("Obtained %zd stack frames.\n", size);
 
249
250	for (i = 0; i < size; i++)
251		printf("%s\n", strings[i]);
252
253	free(strings);
254}
255#else
256void dump_stack(void) {}
257#endif
 
 
 
 
 
258
259void get_term_dimensions(struct winsize *ws)
260{
261	char *s = getenv("LINES");
262
263	if (s != NULL) {
264		ws->ws_row = atoi(s);
265		s = getenv("COLUMNS");
266		if (s != NULL) {
267			ws->ws_col = atoi(s);
268			if (ws->ws_row && ws->ws_col)
269				return;
270		}
271	}
272#ifdef TIOCGWINSZ
273	if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
274	    ws->ws_row && ws->ws_col)
275		return;
276#endif
277	ws->ws_row = 25;
278	ws->ws_col = 80;
279}
280
281static void set_tracing_events_path(const char *mountpoint)
282{
283	snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s",
284		 mountpoint, "tracing/events");
285}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
286
287const char *perf_debugfs_mount(const char *mountpoint)
288{
289	const char *mnt;
290
291	mnt = debugfs_mount(mountpoint);
292	if (!mnt)
293		return NULL;
294
295	set_tracing_events_path(mnt);
296
297	return mnt;
298}
299
300void perf_debugfs_set_path(const char *mntpt)
301{
302	snprintf(debugfs_mountpoint, strlen(debugfs_mountpoint), "%s", mntpt);
303	set_tracing_events_path(mntpt);
304}
305
306static const char *find_debugfs(void)
307{
308	const char *path = perf_debugfs_mount(NULL);
309
310	if (!path)
311		fprintf(stderr, "Your kernel does not support the debugfs filesystem");
312
313	return path;
314}
315
316/*
317 * Finds the path to the debugfs/tracing
318 * Allocates the string and stores it.
319 */
320const char *find_tracing_dir(void)
321{
322	static char *tracing;
323	static int tracing_found;
324	const char *debugfs;
325
326	if (tracing_found)
327		return tracing;
328
329	debugfs = find_debugfs();
330	if (!debugfs)
331		return NULL;
332
333	tracing = malloc(strlen(debugfs) + 9);
334	if (!tracing)
335		return NULL;
336
337	sprintf(tracing, "%s/tracing", debugfs);
338
339	tracing_found = 1;
340	return tracing;
341}
342
343char *get_tracing_file(const char *name)
344{
345	const char *tracing;
346	char *file;
347
348	tracing = find_tracing_dir();
349	if (!tracing)
350		return NULL;
 
 
 
351
352	file = malloc(strlen(tracing) + strlen(name) + 2);
353	if (!file)
354		return NULL;
355
356	sprintf(file, "%s/%s", tracing, name);
357	return file;
358}
359
360void put_tracing_file(char *file)
361{
362	free(file);
363}
364
365int parse_nsec_time(const char *str, u64 *ptime)
366{
367	u64 time_sec, time_nsec;
368	char *end;
369
370	time_sec = strtoul(str, &end, 10);
371	if (*end != '.' && *end != '\0')
372		return -1;
373
374	if (*end == '.') {
375		int i;
376		char nsec_buf[10];
377
378		if (strlen(++end) > 9)
379			return -1;
380
381		strncpy(nsec_buf, end, 9);
382		nsec_buf[9] = '\0';
383
384		/* make it nsec precision */
385		for (i = strlen(nsec_buf); i < 9; i++)
386			nsec_buf[i] = '0';
387
388		time_nsec = strtoul(nsec_buf, &end, 10);
389		if (*end != '\0')
390			return -1;
391	} else
392		time_nsec = 0;
393
394	*ptime = time_sec * NSEC_PER_SEC + time_nsec;
395	return 0;
396}
397
398unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
399{
400	struct parse_tag *i = tags;
401
402	while (i->tag) {
403		char *s;
404
405		s = strchr(str, i->tag);
406		if (s) {
407			unsigned long int value;
408			char *endptr;
409
410			value = strtoul(str, &endptr, 10);
411			if (s != endptr)
412				break;
413
414			if (value > ULONG_MAX / i->mult)
415				break;
416			value *= i->mult;
417			return value;
418		}
419		i++;
420	}
421
422	return (unsigned long) -1;
423}
424
425int filename__read_int(const char *filename, int *value)
426{
427	char line[64];
428	int fd = open(filename, O_RDONLY), err = -1;
429
430	if (fd < 0)
 
 
431		return -1;
432
433	if (read(fd, line, sizeof(line)) > 0) {
434		*value = atoi(line);
435		err = 0;
436	}
437
438	close(fd);
439	return err;
440}
441
442int filename__read_str(const char *filename, char **buf, size_t *sizep)
443{
444	size_t size = 0, alloc_size = 0;
445	void *bf = NULL, *nbf;
446	int fd, n, err = 0;
447
448	fd = open(filename, O_RDONLY);
449	if (fd < 0)
450		return -errno;
451
452	do {
453		if (size == alloc_size) {
454			alloc_size += BUFSIZ;
455			nbf = realloc(bf, alloc_size);
456			if (!nbf) {
457				err = -ENOMEM;
458				break;
459			}
460
461			bf = nbf;
462		}
463
464		n = read(fd, bf + size, alloc_size - size);
465		if (n < 0) {
466			if (size) {
467				pr_warning("read failed %d: %s\n",
468					   errno, strerror(errno));
469				err = 0;
470			} else
471				err = -errno;
472
473			break;
474		}
475
476		size += n;
477	} while (n > 0);
478
479	if (!err) {
480		*sizep = size;
481		*buf   = bf;
482	} else
483		free(bf);
484
485	close(fd);
486	return err;
487}
488
489const char *get_filename_for_perf_kvm(void)
490{
491	const char *filename;
492
493	if (perf_host && !perf_guest)
494		filename = strdup("perf.data.host");
495	else if (!perf_host && perf_guest)
496		filename = strdup("perf.data.guest");
497	else
498		filename = strdup("perf.data.kvm");
499
500	return filename;
501}
502
503int perf_event_paranoid(void)
504{
505	char path[PATH_MAX];
506	const char *procfs = procfs__mountpoint();
507	int value;
508
509	if (!procfs)
510		return INT_MAX;
511
512	scnprintf(path, PATH_MAX, "%s/sys/kernel/perf_event_paranoid", procfs);
513
514	if (filename__read_int(path, &value))
515		return INT_MAX;
516
517	return value;
518}
519
520void mem_bswap_32(void *src, int byte_size)
521{
522	u32 *m = src;
523	while (byte_size > 0) {
524		*m = bswap_32(*m);
525		byte_size -= sizeof(u32);
526		++m;
527	}
528}
529
530void mem_bswap_64(void *src, int byte_size)
531{
532	u64 *m = src;
533
534	while (byte_size > 0) {
535		*m = bswap_64(*m);
536		byte_size -= sizeof(u64);
537		++m;
538	}
539}