linux/tools/perf/util/util.c
Peter Senna Tschudin bf6445631c perf tools: Bool functions shouldn't return -1
Returning a negative value for a boolean function seem to have the
undesired effect of returning true. Replace -1 by false in a
bool-returning function.

The diff of the .s file before and after the change (for x86_64):

  3907c3907
  < 	movl	$1, %ebx
  ---
  > 	xorl	%ebx, %ebx

while if -1 is replaced by true, the diff is empty.

This issue was found by the following Coccinelle semantic patch:

  <smpl>
  @@
  identifier f;
  constant C;
  typedef bool;
  @@
  bool f (...){
  <+...
  * return -C;
  ...+>
  }
  </smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Milos Vyletel <milos@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1442484533-19742-1-git-send-email-peter.senna@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-17 15:31:52 -03:00

738 lines
13 KiB
C

#include "../perf.h"
#include "util.h"
#include "debug.h"
#include <api/fs/fs.h>
#include <sys/mman.h>
#ifdef HAVE_BACKTRACE_SUPPORT
#include <execinfo.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <byteswap.h>
#include <linux/kernel.h>
#include <unistd.h>
#include "callchain.h"
struct callchain_param callchain_param = {
.mode = CHAIN_GRAPH_REL,
.min_percent = 0.5,
.order = ORDER_CALLEE,
.key = CCKEY_FUNCTION
};
/*
* XXX We need to find a better place for these things...
*/
unsigned int page_size;
int cacheline_size;
bool test_attr__enabled;
bool perf_host = true;
bool perf_guest = false;
char tracing_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing";
char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
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(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);
ret = stat(namebuf, &statbuf);
if (ret < 0) {
pr_debug("stat failed: %s\n", namebuf);
break;
}
if (S_ISREG(statbuf.st_mode))
ret = unlink(namebuf);
else if (S_ISDIR(statbuf.st_mode))
ret = rm_rf(namebuf);
else {
pr_debug("unknown file: %s\n", namebuf);
ret = -1;
}
}
closedir(dir);
if (ret < 0)
return ret;
return rmdir(path);
}
static int slow_copyfile(const char *from, const char *to)
{
int err = -1;
char *line = NULL;
size_t n;
FILE *from_fp = fopen(from, "r"), *to_fp;
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;
}
int copyfile_mode(const char *from, const char *to, mode_t mode)
{
int fromfd, tofd;
struct stat st;
int err = -1;
char *tmp = NULL, *ptr = NULL;
if (stat(from, &st))
goto out;
/* 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);
goto out_close_to;
}
fromfd = open(from, O_RDONLY);
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(const char *from, const char *to)
{
return copyfile_mode(from, to, 0755);
}
unsigned long convert_unit(unsigned long value, char *unit)
{
*unit = ' ';
if (value > 1000) {
value /= 1000;
*unit = 'K';
}
if (value > 1000) {
value /= 1000;
*unit = 'M';
}
if (value > 1000) {
value /= 1000;
*unit = 'G';
}
return value;
}
static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
{
void *buf_start = buf;
size_t left = n;
while (left) {
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, void *buf, size_t n)
{
return ion(false, fd, 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;
}
/* Obtain a backtrace and print it to stdout. */
#ifdef HAVE_BACKTRACE_SUPPORT
void dump_stack(void)
{
void *array[16];
size_t size = backtrace(array, ARRAY_SIZE(array));
char **strings = backtrace_symbols(array, size);
size_t i;
printf("Obtained %zd stack frames.\n", size);
for (i = 0; i < size; i++)
printf("%s\n", strings[i]);
free(strings);
}
#else
void dump_stack(void) {}
#endif
void sighandler_dump_stack(int sig)
{
psignal(sig, "perf");
dump_stack();
exit(sig);
}
void get_term_dimensions(struct winsize *ws)
{
char *s = getenv("LINES");
if (s != NULL) {
ws->ws_row = atoi(s);
s = getenv("COLUMNS");
if (s != NULL) {
ws->ws_col = atoi(s);
if (ws->ws_row && ws->ws_col)
return;
}
}
#ifdef TIOCGWINSZ
if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
ws->ws_row && ws->ws_col)
return;
#endif
ws->ws_row = 25;
ws->ws_col = 80;
}
void set_term_quiet_input(struct termios *old)
{
struct termios tc;
tcgetattr(0, old);
tc = *old;
tc.c_lflag &= ~(ICANON | ECHO);
tc.c_cc[VMIN] = 0;
tc.c_cc[VTIME] = 0;
tcsetattr(0, TCSANOW, &tc);
}
static void set_tracing_events_path(const char *tracing, const char *mountpoint)
{
snprintf(tracing_path, sizeof(tracing_path), "%s/%s",
mountpoint, tracing);
snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
mountpoint, tracing, "events");
}
static const char *__perf_tracefs_mount(const char *mountpoint)
{
const char *mnt;
mnt = tracefs_mount(mountpoint);
if (!mnt)
return NULL;
set_tracing_events_path("", mnt);
return mnt;
}
static const char *__perf_debugfs_mount(const char *mountpoint)
{
const char *mnt;
mnt = debugfs_mount(mountpoint);
if (!mnt)
return NULL;
set_tracing_events_path("tracing/", mnt);
return mnt;
}
const char *perf_debugfs_mount(const char *mountpoint)
{
const char *mnt;
mnt = __perf_tracefs_mount(mountpoint);
if (mnt)
return mnt;
mnt = __perf_debugfs_mount(mountpoint);
return mnt;
}
void perf_debugfs_set_path(const char *mntpt)
{
set_tracing_events_path("tracing/", mntpt);
}
char *get_tracing_file(const char *name)
{
char *file;
if (asprintf(&file, "%s/%s", tracing_path, name) < 0)
return NULL;
return file;
}
void put_tracing_file(char *file)
{
free(file);
}
int parse_nsec_time(const char *str, u64 *ptime)
{
u64 time_sec, time_nsec;
char *end;
time_sec = strtoul(str, &end, 10);
if (*end != '.' && *end != '\0')
return -1;
if (*end == '.') {
int i;
char nsec_buf[10];
if (strlen(++end) > 9)
return -1;
strncpy(nsec_buf, end, 9);
nsec_buf[9] = '\0';
/* make it nsec precision */
for (i = strlen(nsec_buf); i < 9; i++)
nsec_buf[i] = '0';
time_nsec = strtoul(nsec_buf, &end, 10);
if (*end != '\0')
return -1;
} else
time_nsec = 0;
*ptime = time_sec * NSEC_PER_SEC + time_nsec;
return 0;
}
unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
{
struct parse_tag *i = tags;
while (i->tag) {
char *s;
s = strchr(str, i->tag);
if (s) {
unsigned long int value;
char *endptr;
value = strtoul(str, &endptr, 10);
if (s != endptr)
break;
if (value > ULONG_MAX / i->mult)
break;
value *= i->mult;
return value;
}
i++;
}
return (unsigned long) -1;
}
int get_stack_size(const char *str, unsigned long *_size)
{
char *endptr;
unsigned long size;
unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
size = strtoul(str, &endptr, 0);
do {
if (*endptr)
break;
size = round_up(size, sizeof(u64));
if (!size || size > max_size)
break;
*_size = size;
return 0;
} while (0);
pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
max_size, str);
return -1;
}
int parse_callchain_record(const char *arg, struct callchain_param *param)
{
char *tok, *name, *saveptr = NULL;
char *buf;
int ret = -1;
/* We need buffer that we know we can write to. */
buf = malloc(strlen(arg) + 1);
if (!buf)
return -ENOMEM;
strcpy(buf, arg);
tok = strtok_r((char *)buf, ",", &saveptr);
name = tok ? : (char *)buf;
do {
/* Framepointer style */
if (!strncmp(name, "fp", sizeof("fp"))) {
if (!strtok_r(NULL, ",", &saveptr)) {
param->record_mode = CALLCHAIN_FP;
ret = 0;
} else
pr_err("callchain: No more arguments "
"needed for --call-graph fp\n");
break;
#ifdef HAVE_DWARF_UNWIND_SUPPORT
/* Dwarf style */
} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
const unsigned long default_stack_dump_size = 8192;
ret = 0;
param->record_mode = CALLCHAIN_DWARF;
param->dump_size = default_stack_dump_size;
tok = strtok_r(NULL, ",", &saveptr);
if (tok) {
unsigned long size = 0;
ret = get_stack_size(tok, &size);
param->dump_size = size;
}
#endif /* HAVE_DWARF_UNWIND_SUPPORT */
} else if (!strncmp(name, "lbr", sizeof("lbr"))) {
if (!strtok_r(NULL, ",", &saveptr)) {
param->record_mode = CALLCHAIN_LBR;
ret = 0;
} else
pr_err("callchain: No more arguments "
"needed for --call-graph lbr\n");
break;
} else {
pr_err("callchain: Unknown --call-graph option "
"value: %s\n", arg);
break;
}
} while (0);
free(buf);
return ret;
}
int filename__read_str(const char *filename, char **buf, size_t *sizep)
{
size_t size = 0, alloc_size = 0;
void *bf = NULL, *nbf;
int fd, n, err = 0;
char sbuf[STRERR_BUFSIZE];
fd = open(filename, O_RDONLY);
if (fd < 0)
return -errno;
do {
if (size == alloc_size) {
alloc_size += BUFSIZ;
nbf = realloc(bf, alloc_size);
if (!nbf) {
err = -ENOMEM;
break;
}
bf = nbf;
}
n = read(fd, bf + size, alloc_size - size);
if (n < 0) {
if (size) {
pr_warning("read failed %d: %s\n", errno,
strerror_r(errno, sbuf, sizeof(sbuf)));
err = 0;
} else
err = -errno;
break;
}
size += n;
} while (n > 0);
if (!err) {
*sizep = size;
*buf = bf;
} else
free(bf);
close(fd);
return err;
}
const char *get_filename_for_perf_kvm(void)
{
const char *filename;
if (perf_host && !perf_guest)
filename = strdup("perf.data.host");
else if (!perf_host && perf_guest)
filename = strdup("perf.data.guest");
else
filename = strdup("perf.data.kvm");
return filename;
}
int perf_event_paranoid(void)
{
int value;
if (sysctl__read_int("kernel/perf_event_paranoid", &value))
return INT_MAX;
return value;
}
void mem_bswap_32(void *src, int byte_size)
{
u32 *m = src;
while (byte_size > 0) {
*m = bswap_32(*m);
byte_size -= sizeof(u32);
++m;
}
}
void mem_bswap_64(void *src, int byte_size)
{
u64 *m = src;
while (byte_size > 0) {
*m = bswap_64(*m);
byte_size -= sizeof(u64);
++m;
}
}
bool find_process(const char *name)
{
size_t len = strlen(name);
DIR *dir;
struct dirent *d;
int ret = -1;
dir = opendir(procfs__mountpoint());
if (!dir)
return false;
/* Walk through the directory. */
while (ret && (d = readdir(dir)) != NULL) {
char path[PATH_MAX];
char *data;
size_t size;
if ((d->d_type != DT_DIR) ||
!strcmp(".", d->d_name) ||
!strcmp("..", d->d_name))
continue;
scnprintf(path, sizeof(path), "%s/%s/comm",
procfs__mountpoint(), d->d_name);
if (filename__read_str(path, &data, &size))
continue;
ret = strncmp(name, data, len);
free(data);
}
closedir(dir);
return ret ? false : true;
}