tools/perf/util/util.c - arm/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 #include "../perf.h"
 #include "util.h"
 #include "debug.h"
 #include <api/fs/fs.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/utsname.h>
 #include <dirent.h>
 #include <inttypes.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 #include <limits.h>
 #include <linux/kernel.h>
 #include <linux/log2.h>
 #include <linux/time64.h>
 #include <unistd.h>
 #include "strlist.h"

 /*
  * XXX We need to find a better place for these things...
  */
 unsigned int page_size;
 int cacheline_size;

 int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
 int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;

 bool test_attr__enabled;

 bool perf_host  = true;
 bool perf_guest = false;

 void event_attr_init(struct perf_event_attr *attr)
 {
 	if (!perf_host)
 		attr->exclude_host  = 1;
 	if (!perf_guest)
 		attr->exclude_guest = 1;
 	/* to capture ABI version */
 	attr->size = sizeof(*attr);
 }

 int mkdir_p(char *path, mode_t mode)
 {
 	struct stat st;
 	int err;
 	char *d = path;

 	if (*d != '/')
 		return -1;

 	if (stat(path, &st) == 0)
 		return 0;

 	while (*++d == '/');

 	while ((d = strchr(d, '/'))) {
 		*d = '\0';
 		err = stat(path, &st) && mkdir(path, mode);
 		*d++ = '/';
 		if (err)
 			return -1;
 		while (*d == '/')
 			++d;
 	}
 	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
 }

 int rm_rf(const char *path)
 {
 	DIR *dir;
 	int ret = 0;
 	struct dirent *d;
 	char namebuf[PATH_MAX];

 	dir = opendir(path);
 	if (dir == NULL)
 		return 0;

 	while ((d = readdir(dir)) != NULL && !ret) {
 		struct stat statbuf;

 		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
 			continue;

 		scnprintf(namebuf, sizeof(namebuf), "%s/%s",
 			  path, d->d_name);

 		/* We have to check symbolic link itself */
 		ret = lstat(namebuf, &statbuf);
 		if (ret < 0) {
 			pr_debug("stat failed: %s\n", namebuf);
 			break;
 		}

 		if (S_ISDIR(statbuf.st_mode))
 			ret = rm_rf(namebuf);
 		else
 			ret = unlink(namebuf);
 	}
 	closedir(dir);

 	if (ret < 0)
 		return ret;

 	return rmdir(path);
 }

 /* A filter which removes dot files */
 bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
 {
 	return d->d_name[0] != '.';
 }

 /* lsdir reads a directory and store it in strlist */
 struct strlist *lsdir(const char *name,
 		      bool (*filter)(const char *, struct dirent *))
 {
 	struct strlist *list = NULL;
 	DIR *dir;
 	struct dirent *d;

 	dir = opendir(name);
 	if (!dir)
 		return NULL;

 	list = strlist__new(NULL, NULL);
 	if (!list) {
 		errno = ENOMEM;
 		goto out;
 	}

 	while ((d = readdir(dir)) != NULL) {
 		if (!filter || filter(name, d))
 			strlist__add(list, d->d_name);
 	}

 out:
 	closedir(dir);
 	return list;
 }

 static int slow_copyfile(const char *from, const char *to, struct nsinfo *nsi)
 {
 	int err = -1;
 	char *line = NULL;
 	size_t n;
 	FILE *from_fp, *to_fp;
 	struct nscookie nsc;

 	nsinfo__mountns_enter(nsi, &nsc);
 	from_fp = fopen(from, "r");
 	nsinfo__mountns_exit(&nsc);
 	if (from_fp == NULL)
 		goto out;

 	to_fp = fopen(to, "w");
 	if (to_fp == NULL)
 		goto out_fclose_from;

 	while (getline(&line, &n, from_fp) > 0)
 		if (fputs(line, to_fp) == EOF)
 			goto out_fclose_to;
 	err = 0;
 out_fclose_to:
 	fclose(to_fp);
 	free(line);
 out_fclose_from:
 	fclose(from_fp);
 out:
 	return err;
 }

 int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
 {
 	void *ptr;
 	loff_t pgoff;

 	pgoff = off_in & ~(page_size - 1);
 	off_in -= pgoff;

 	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
 	if (ptr == MAP_FAILED)
 		return -1;

 	while (size) {
 		ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
 		if (ret < 0 && errno == EINTR)
 			continue;
 		if (ret <= 0)
 			break;

 		size -= ret;
 		off_in += ret;
 		off_out -= ret;
 	}
 	munmap(ptr, off_in + size);

 	return size ? -1 : 0;
 }

 static int copyfile_mode_ns(const char *from, const char *to, mode_t mode,
 			    struct nsinfo *nsi)
 {
 	int fromfd, tofd;
 	struct stat st;
 	int err;
 	char *tmp = NULL, *ptr = NULL;
 	struct nscookie nsc;

 	nsinfo__mountns_enter(nsi, &nsc);
 	err = stat(from, &st);
 	nsinfo__mountns_exit(&nsc);
 	if (err)
 		goto out;
 	err = -1;

 	/* extra 'x' at the end is to reserve space for '.' */
 	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
 		tmp = NULL;
 		goto out;
 	}
 	ptr = strrchr(tmp, '/');
 	if (!ptr)
 		goto out;
 	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
 	*ptr = '.';

 	tofd = mkstemp(tmp);
 	if (tofd < 0)
 		goto out;

 	if (fchmod(tofd, mode))
 		goto out_close_to;

 	if (st.st_size == 0) { /* /proc? do it slowly... */
 		err = slow_copyfile(from, tmp, nsi);
 		goto out_close_to;
 	}

 	nsinfo__mountns_enter(nsi, &nsc);
 	fromfd = open(from, O_RDONLY);
 	nsinfo__mountns_exit(&nsc);
 	if (fromfd < 0)
 		goto out_close_to;

 	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);

 	close(fromfd);
 out_close_to:
 	close(tofd);
 	if (!err)
 		err = link(tmp, to);
 	unlink(tmp);
 out:
 	free(tmp);
 	return err;
 }

 int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi)
 {
 	return copyfile_mode_ns(from, to, 0755, nsi);
 }

 int copyfile_mode(const char *from, const char *to, mode_t mode)
 {
 	return copyfile_mode_ns(from, to, mode, NULL);
 }

 int copyfile(const char *from, const char *to)
 {
 	return copyfile_mode(from, to, 0755);
 }

 static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
 {
 	void *buf_start = buf;
 	size_t left = n;

 	while (left) {
 		/* buf must be treated as const if !is_read. */
 		ssize_t ret = is_read ? read(fd, buf, left) :
 					write(fd, buf, left);

 		if (ret < 0 && errno == EINTR)
 			continue;
 		if (ret <= 0)
 			return ret;

 		left -= ret;
 		buf  += ret;
 	}

 	BUG_ON((size_t)(buf - buf_start) != n);
 	return n;
 }

 /*
  * Read exactly 'n' bytes or return an error.
  */
 ssize_t readn(int fd, void *buf, size_t n)
 {
 	return ion(true, fd, buf, n);
 }

 /*
  * Write exactly 'n' bytes or return an error.
  */
 ssize_t writen(int fd, const void *buf, size_t n)
 {
 	/* ion does not modify buf. */
 	return ion(false, fd, (void *)buf, n);
 }

 size_t hex_width(u64 v)
 {
 	size_t n = 1;

 	while ((v >>= 4))
 		++n;

 	return n;
 }

 static int hex(char ch)
 {
 	if ((ch >= '0') && (ch <= '9'))
 		return ch - '0';
 	if ((ch >= 'a') && (ch <= 'f'))
 		return ch - 'a' + 10;
 	if ((ch >= 'A') && (ch <= 'F'))
 		return ch - 'A' + 10;
 	return -1;
 }

 /*
  * While we find nice hex chars, build a long_val.
  * Return number of chars processed.
  */
 int hex2u64(const char *ptr, u64 *long_val)
 {
 	const char *p = ptr;
 	*long_val = 0;

 	while (*p) {
 		const int hex_val = hex(*p);

 		if (hex_val < 0)
 			break;

 		*long_val = (*long_val << 4) | hex_val;
 		p++;
 	}

 	return p - ptr;
 }

 int perf_event_paranoid(void)
 {
 	int value;

 	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
 		return INT_MAX;

 	return value;
 }
 static int
 fetch_ubuntu_kernel_version(unsigned int *puint)
 {
 	ssize_t len;
 	size_t line_len = 0;
 	char *ptr, *line = NULL;
 	int version, patchlevel, sublevel, err;
 	FILE *vsig;

 	if (!puint)
 		return 0;

 	vsig = fopen("/proc/version_signature", "r");
 	if (!vsig) {
 		pr_debug("Open /proc/version_signature failed: %s\n",
 			 strerror(errno));
 		return -1;
 	}

 	len = getline(&line, &line_len, vsig);
 	fclose(vsig);
 	err = -1;
 	if (len <= 0) {
 		pr_debug("Reading from /proc/version_signature failed: %s\n",
 			 strerror(errno));
 		goto errout;
 	}

 	ptr = strrchr(line, ' ');
 	if (!ptr) {
 		pr_debug("Parsing /proc/version_signature failed: %s\n", line);
 		goto errout;
 	}

 	err = sscanf(ptr + 1, "%d.%d.%d",
 		     &version, &patchlevel, &sublevel);
 	if (err != 3) {
 		pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
 			 line);
 		goto errout;
 	}

 	*puint = (version << 16) + (patchlevel << 8) + sublevel;
 	err = 0;
 errout:
 	free(line);
 	return err;
 }

 int
 fetch_kernel_version(unsigned int *puint, char *str,
 		     size_t str_size)
 {
 	struct utsname utsname;
 	int version, patchlevel, sublevel, err;
 	bool int_ver_ready = false;

 	if (access("/proc/version_signature", R_OK) == 0)
 		if (!fetch_ubuntu_kernel_version(puint))
 			int_ver_ready = true;

 	if (uname(&utsname))
 		return -1;

 	if (str && str_size) {
 		strncpy(str, utsname.release, str_size);
 		str[str_size - 1] = '\0';
 	}

 	if (!puint || int_ver_ready)
 		return 0;

 	err = sscanf(utsname.release, "%d.%d.%d",
 		     &version, &patchlevel, &sublevel);

 	if (err != 3) {
 		pr_debug("Unable to get kernel version from uname '%s'\n",
 			 utsname.release);
 		return -1;
 	}

 	*puint = (version << 16) + (patchlevel << 8) + sublevel;
 	return 0;
 }

 const char *perf_tip(const char *dirpath)
 {
 	struct strlist *tips;
 	struct str_node *node;
 	char *tip = NULL;
 	struct strlist_config conf = {
 		.dirname = dirpath,
 		.file_only = true,
 	};

 	tips = strlist__new("tips.txt", &conf);
 	if (tips == NULL)
 		return errno == ENOENT ? NULL :
 			"Tip: check path of tips.txt or get more memory! ;-p";

 	if (strlist__nr_entries(tips) == 0)
 		goto out;

 	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
 	if (asprintf(&tip, "Tip: %s", node->s) < 0)
 		tip = (char *)"Tip: get more memory! ;-)";

 out:
 	strlist__delete(tips);

 	return tip;
 }
	// SPDX-License-Identifier: GPL-2.0
	#include "../perf.h"
	#include "util.h"
	#include "debug.h"
	#include <api/fs/fs.h>
	#include <sys/mman.h>
	#include <sys/stat.h>
	#include <sys/utsname.h>
	#include <dirent.h>
	#include <inttypes.h>
	#include <signal.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <errno.h>
	#include <limits.h>
	#include <linux/kernel.h>
	#include <linux/log2.h>
	#include <linux/time64.h>
	#include <unistd.h>
	#include "strlist.h"

	/*
	* XXX We need to find a better place for these things...
	*/
	unsigned int page_size;
	int cacheline_size;

	int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
	int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;

	bool test_attr__enabled;

	bool perf_host = true;
	bool perf_guest = false;

	void event_attr_init(struct perf_event_attr *attr)
	{
	if (!perf_host)
	attr->exclude_host = 1;
	if (!perf_guest)
	attr->exclude_guest = 1;
	/* to capture ABI version */
	attr->size = sizeof(*attr);
	}

	int mkdir_p(char *path, mode_t mode)
	{
	struct stat st;
	int err;
	char *d = path;

	if (*d != '/')
	return -1;

	if (stat(path, &st) == 0)
	return 0;

	while (*++d == '/');

	while ((d = strchr(d, '/'))) {
	*d = '\0';
	err = stat(path, &st) && mkdir(path, mode);
	*d++ = '/';
	if (err)
	return -1;
	while (*d == '/')
	++d;
	}
	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
	}

	int rm_rf(const char *path)
	{
	DIR *dir;
	int ret = 0;
	struct dirent *d;
	char namebuf[PATH_MAX];

	dir = opendir(path);
	if (dir == NULL)
	return 0;

	while ((d = readdir(dir)) != NULL && !ret) {
	struct stat statbuf;

	if (!strcmp(d->d_name, ".") \|\| !strcmp(d->d_name, ".."))
	continue;

	scnprintf(namebuf, sizeof(namebuf), "%s/%s",
	path, d->d_name);

	/* We have to check symbolic link itself */
	ret = lstat(namebuf, &statbuf);
	if (ret < 0) {
	pr_debug("stat failed: %s\n", namebuf);
	break;
	}

	if (S_ISDIR(statbuf.st_mode))
	ret = rm_rf(namebuf);
	else
	ret = unlink(namebuf);
	}
	closedir(dir);

	if (ret < 0)
	return ret;

	return rmdir(path);
	}

	/* A filter which removes dot files */
	bool lsdir_no_dot_filter(const char name __maybe_unused, struct dirent d)
	{
	return d->d_name[0] != '.';
	}

	/* lsdir reads a directory and store it in strlist */
	struct strlist lsdir(const char name,
	bool (filter)(const char , struct dirent *))
	{
	struct strlist *list = NULL;
	DIR *dir;
	struct dirent *d;

	dir = opendir(name);
	if (!dir)
	return NULL;

	list = strlist__new(NULL, NULL);
	if (!list) {
	errno = ENOMEM;
	goto out;
	}

	while ((d = readdir(dir)) != NULL) {
	if (!filter \|\| filter(name, d))
	strlist__add(list, d->d_name);
	}

	out:
	closedir(dir);
	return list;
	}

	static int slow_copyfile(const char from, const char to, struct nsinfo *nsi)
	{
	int err = -1;
	char *line = NULL;
	size_t n;
	FILE from_fp, to_fp;
	struct nscookie nsc;

	nsinfo__mountns_enter(nsi, &nsc);
	from_fp = fopen(from, "r");
	nsinfo__mountns_exit(&nsc);
	if (from_fp == NULL)
	goto out;

	to_fp = fopen(to, "w");
	if (to_fp == NULL)
	goto out_fclose_from;

	while (getline(&line, &n, from_fp) > 0)
	if (fputs(line, to_fp) == EOF)
	goto out_fclose_to;
	err = 0;
	out_fclose_to:
	fclose(to_fp);
	free(line);
	out_fclose_from:
	fclose(from_fp);
	out:
	return err;
	}

	int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
	{
	void *ptr;
	loff_t pgoff;

	pgoff = off_in & ~(page_size - 1);
	off_in -= pgoff;

	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
	if (ptr == MAP_FAILED)
	return -1;

	while (size) {
	ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
	if (ret < 0 && errno == EINTR)
	continue;
	if (ret <= 0)
	break;

	size -= ret;
	off_in += ret;
	off_out -= ret;
	}
	munmap(ptr, off_in + size);

	return size ? -1 : 0;
	}

	static int copyfile_mode_ns(const char from, const char to, mode_t mode,
	struct nsinfo *nsi)
	{
	int fromfd, tofd;
	struct stat st;
	int err;
	char tmp = NULL, ptr = NULL;
	struct nscookie nsc;

	nsinfo__mountns_enter(nsi, &nsc);
	err = stat(from, &st);
	nsinfo__mountns_exit(&nsc);
	if (err)
	goto out;
	err = -1;

	/* extra 'x' at the end is to reserve space for '.' */
	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
	tmp = NULL;
	goto out;
	}
	ptr = strrchr(tmp, '/');
	if (!ptr)
	goto out;
	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
	*ptr = '.';

	tofd = mkstemp(tmp);
	if (tofd < 0)
	goto out;

	if (fchmod(tofd, mode))
	goto out_close_to;

	if (st.st_size == 0) { /* /proc? do it slowly... */
	err = slow_copyfile(from, tmp, nsi);
	goto out_close_to;
	}

	nsinfo__mountns_enter(nsi, &nsc);
	fromfd = open(from, O_RDONLY);
	nsinfo__mountns_exit(&nsc);
	if (fromfd < 0)
	goto out_close_to;

	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);

	close(fromfd);
	out_close_to:
	close(tofd);
	if (!err)
	err = link(tmp, to);
	unlink(tmp);
	out:
	free(tmp);
	return err;
	}

	int copyfile_ns(const char from, const char to, struct nsinfo *nsi)
	{
	return copyfile_mode_ns(from, to, 0755, nsi);
	}

	int copyfile_mode(const char from, const char to, mode_t mode)
	{
	return copyfile_mode_ns(from, to, mode, NULL);
	}

	int copyfile(const char from, const char to)
	{
	return copyfile_mode(from, to, 0755);
	}

	static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
	{
	void *buf_start = buf;
	size_t left = n;

	while (left) {
	/* buf must be treated as const if !is_read. */
	ssize_t ret = is_read ? read(fd, buf, left) :
	write(fd, buf, left);

	if (ret < 0 && errno == EINTR)
	continue;
	if (ret <= 0)
	return ret;

	left -= ret;
	buf += ret;
	}

	BUG_ON((size_t)(buf - buf_start) != n);
	return n;
	}

	/*
	* Read exactly 'n' bytes or return an error.
	*/
	ssize_t readn(int fd, void *buf, size_t n)
	{
	return ion(true, fd, buf, n);
	}

	/*
	* Write exactly 'n' bytes or return an error.
	*/
	ssize_t writen(int fd, const void *buf, size_t n)
	{
	/* ion does not modify buf. */
	return ion(false, fd, (void *)buf, n);
	}

	size_t hex_width(u64 v)
	{
	size_t n = 1;

	while ((v >>= 4))
	++n;

	return n;
	}

	static int hex(char ch)
	{
	if ((ch >= '0') && (ch <= '9'))
	return ch - '0';
	if ((ch >= 'a') && (ch <= 'f'))
	return ch - 'a' + 10;
	if ((ch >= 'A') && (ch <= 'F'))
	return ch - 'A' + 10;
	return -1;
	}

	/*
	* While we find nice hex chars, build a long_val.
	* Return number of chars processed.
	*/
	int hex2u64(const char ptr, u64 long_val)
	{
	const char *p = ptr;
	*long_val = 0;

	while (*p) {
	const int hex_val = hex(*p);

	if (hex_val < 0)
	break;

	long_val = (long_val << 4) \| hex_val;
	p++;
	}

	return p - ptr;
	}

	int perf_event_paranoid(void)
	{
	int value;

	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
	return INT_MAX;

	return value;
	}
	static int
	fetch_ubuntu_kernel_version(unsigned int *puint)
	{
	ssize_t len;
	size_t line_len = 0;
	char ptr, line = NULL;
	int version, patchlevel, sublevel, err;
	FILE *vsig;

	if (!puint)
	return 0;

	vsig = fopen("/proc/version_signature", "r");
	if (!vsig) {
	pr_debug("Open /proc/version_signature failed: %s\n",
	strerror(errno));
	return -1;
	}

	len = getline(&line, &line_len, vsig);
	fclose(vsig);
	err = -1;
	if (len <= 0) {
	pr_debug("Reading from /proc/version_signature failed: %s\n",
	strerror(errno));
	goto errout;
	}

	ptr = strrchr(line, ' ');
	if (!ptr) {
	pr_debug("Parsing /proc/version_signature failed: %s\n", line);
	goto errout;
	}

	err = sscanf(ptr + 1, "%d.%d.%d",
	&version, &patchlevel, &sublevel);
	if (err != 3) {
	pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
	line);
	goto errout;
	}

	*puint = (version << 16) + (patchlevel << 8) + sublevel;
	err = 0;
	errout:
	free(line);
	return err;
	}

	int
	fetch_kernel_version(unsigned int puint, char str,
	size_t str_size)
	{
	struct utsname utsname;
	int version, patchlevel, sublevel, err;
	bool int_ver_ready = false;

	if (access("/proc/version_signature", R_OK) == 0)
	if (!fetch_ubuntu_kernel_version(puint))
	int_ver_ready = true;

	if (uname(&utsname))
	return -1;

	if (str && str_size) {
	strncpy(str, utsname.release, str_size);
	str[str_size - 1] = '\0';
	}

	if (!puint \|\| int_ver_ready)
	return 0;

	err = sscanf(utsname.release, "%d.%d.%d",
	&version, &patchlevel, &sublevel);

	if (err != 3) {
	pr_debug("Unable to get kernel version from uname '%s'\n",
	utsname.release);
	return -1;
	}

	*puint = (version << 16) + (patchlevel << 8) + sublevel;
	return 0;
	}

	const char perf_tip(const char dirpath)
	{
	struct strlist *tips;
	struct str_node *node;
	char *tip = NULL;
	struct strlist_config conf = {
	.dirname = dirpath,
	.file_only = true,
	};

	tips = strlist__new("tips.txt", &conf);
	if (tips == NULL)
	return errno == ENOENT ? NULL :
	"Tip: check path of tips.txt or get more memory! ;-p";

	if (strlist__nr_entries(tips) == 0)
	goto out;

	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
	if (asprintf(&tip, "Tip: %s", node->s) < 0)
	tip = (char *)"Tip: get more memory! ;-)";

	out:
	strlist__delete(tips);

	return tip;
	}