linux_dsm_epyc7002/tools/perf/util/srcline.c
David Ahern a949fffb84 perf tools: Fix old GCC build error in 'get_srcline'
trace-event-parse.c:parse_proc_kallsyms()

    Old GCC (4.4.2) does not see through the code flow of get_srcline() and
gets confused about the status of 'file' and 'line':

    CC       /tmp/build/perf/util/srcline.o
  cc1: warnings being treated as errors
  util/srcline.c: In function ¿get_srcline¿:
  util/srcline.c:226: error: ¿file¿ may be used uninitialized in this function
  util/srcline.c:227: error: ¿line¿ may be used uninitialized in this function
  make[1]: *** [/tmp/build/perf/util/srcline.o] Error 1
  make: *** [install] Error 2
  make: Leaving directory `/home/acme/git/linux/tools/perf'
  [acme@fedora12 linux]$

Help out GCC by initializing 'file' and 'line'.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/n/tip-h8k7h49z3cndqgjdftkmm9f8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-14 10:28:52 -03:00

266 lines
4.7 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <linux/kernel.h>
#include "util/dso.h"
#include "util/util.h"
#include "util/debug.h"
#ifdef HAVE_LIBBFD_SUPPORT
/*
* Implement addr2line using libbfd.
*/
#define PACKAGE "perf"
#include <bfd.h>
struct a2l_data {
const char *input;
unsigned long addr;
bool found;
const char *filename;
const char *funcname;
unsigned line;
bfd *abfd;
asymbol **syms;
};
static int bfd_error(const char *string)
{
const char *errmsg;
errmsg = bfd_errmsg(bfd_get_error());
fflush(stdout);
if (string)
pr_debug("%s: %s\n", string, errmsg);
else
pr_debug("%s\n", errmsg);
return -1;
}
static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
{
long storage;
long symcount;
asymbol **syms;
bfd_boolean dynamic = FALSE;
if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
return bfd_error(bfd_get_filename(abfd));
storage = bfd_get_symtab_upper_bound(abfd);
if (storage == 0L) {
storage = bfd_get_dynamic_symtab_upper_bound(abfd);
dynamic = TRUE;
}
if (storage < 0L)
return bfd_error(bfd_get_filename(abfd));
syms = malloc(storage);
if (dynamic)
symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
else
symcount = bfd_canonicalize_symtab(abfd, syms);
if (symcount < 0) {
free(syms);
return bfd_error(bfd_get_filename(abfd));
}
a2l->syms = syms;
return 0;
}
static void find_address_in_section(bfd *abfd, asection *section, void *data)
{
bfd_vma pc, vma;
bfd_size_type size;
struct a2l_data *a2l = data;
if (a2l->found)
return;
if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0)
return;
pc = a2l->addr;
vma = bfd_get_section_vma(abfd, section);
size = bfd_get_section_size(section);
if (pc < vma || pc >= vma + size)
return;
a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
&a2l->filename, &a2l->funcname,
&a2l->line);
}
static struct a2l_data *addr2line_init(const char *path)
{
bfd *abfd;
struct a2l_data *a2l = NULL;
abfd = bfd_openr(path, NULL);
if (abfd == NULL)
return NULL;
if (!bfd_check_format(abfd, bfd_object))
goto out;
a2l = zalloc(sizeof(*a2l));
if (a2l == NULL)
goto out;
a2l->abfd = abfd;
a2l->input = strdup(path);
if (a2l->input == NULL)
goto out;
if (slurp_symtab(abfd, a2l))
goto out;
return a2l;
out:
if (a2l) {
free((void *)a2l->input);
free(a2l);
}
bfd_close(abfd);
return NULL;
}
static void addr2line_cleanup(struct a2l_data *a2l)
{
if (a2l->abfd)
bfd_close(a2l->abfd);
free((void *)a2l->input);
free(a2l->syms);
free(a2l);
}
static int addr2line(const char *dso_name, unsigned long addr,
char **file, unsigned int *line)
{
int ret = 0;
struct a2l_data *a2l;
a2l = addr2line_init(dso_name);
if (a2l == NULL) {
pr_warning("addr2line_init failed for %s\n", dso_name);
return 0;
}
a2l->addr = addr;
bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
if (a2l->found && a2l->filename) {
*file = strdup(a2l->filename);
*line = a2l->line;
if (*file)
ret = 1;
}
addr2line_cleanup(a2l);
return ret;
}
#else /* HAVE_LIBBFD_SUPPORT */
static int addr2line(const char *dso_name, unsigned long addr,
char **file, unsigned int *line_nr)
{
FILE *fp;
char cmd[PATH_MAX];
char *filename = NULL;
size_t len;
char *sep;
int ret = 0;
scnprintf(cmd, sizeof(cmd), "addr2line -e %s %016"PRIx64,
dso_name, addr);
fp = popen(cmd, "r");
if (fp == NULL) {
pr_warning("popen failed for %s\n", dso_name);
return 0;
}
if (getline(&filename, &len, fp) < 0 || !len) {
pr_warning("addr2line has no output for %s\n", dso_name);
goto out;
}
sep = strchr(filename, '\n');
if (sep)
*sep = '\0';
if (!strcmp(filename, "??:0")) {
pr_debug("no debugging info in %s\n", dso_name);
free(filename);
goto out;
}
sep = strchr(filename, ':');
if (sep) {
*sep++ = '\0';
*file = filename;
*line_nr = strtoul(sep, NULL, 0);
ret = 1;
}
out:
pclose(fp);
return ret;
}
#endif /* HAVE_LIBBFD_SUPPORT */
char *get_srcline(struct dso *dso, unsigned long addr)
{
char *file = NULL;
unsigned line = 0;
char *srcline;
char *dso_name = dso->long_name;
size_t size;
if (!dso->has_srcline)
return SRCLINE_UNKNOWN;
if (dso_name[0] == '[')
goto out;
if (!strncmp(dso_name, "/tmp/perf-", 10))
goto out;
if (!addr2line(dso_name, addr, &file, &line))
goto out;
/* just calculate actual length */
size = snprintf(NULL, 0, "%s:%u", file, line) + 1;
srcline = malloc(size);
if (srcline)
snprintf(srcline, size, "%s:%u", file, line);
else
srcline = SRCLINE_UNKNOWN;
free(file);
return srcline;
out:
dso->has_srcline = 0;
return SRCLINE_UNKNOWN;
}
void free_srcline(char *srcline)
{
if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
free(srcline);
}