linux/tools/perf/util/util.c
David Carrillo-Cisneros 7c72440506 perf util: Add const modifier to buf in "writen" function
Make buf in helper function "writen" constant to simplify the life of
its callers.

This requires to hack a cast of buf prior to passing it to "ion" which
is simpler than the alternative of reworking the "ion" function to
provide a read and a write paths, the latter with constant buf argument.

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170718042549.145161-5-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18 23:14:29 -03:00

482 lines
8.8 KiB
C

#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;
}