[PATCH v2 1/3] perf annotate: Get correct line numbers matched with addr

From: Taeung Song
Date: Tue Feb 28 2017 - 15:00:59 EST


Currently perf-annotate show wrong line numbers.

For example,
Actual source code is as below

...
21 };
22
23 unsigned int limited_wgt;
24
25 unsigned int get_cond_maxprice(int wgt)
26 {
...

However, the output of perf-annotate is as below.

4 Disassembly of section .text:

6 0000000000400966 <get_cond_maxprice>:
7 get_cond_maxprice():
26 };

28 unsigned int limited_wgt;

30 unsigned int get_cond_maxprice(int wgt)
31 {

The cause is the wrong way counting line numbers
in symbol__parse_objdump_line().
So remove wrong current code counting line number and
use other method for it using functions related to addr2line
instead of the output of '-l' of objdump.

However, despite the correct line numbers,
we can't show proper source code view
because of limitations from output of 'objdump -S'.

So, next commit will resolve the limitations from 'objdump -S'
with the new source code view.

Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
---
tools/perf/util/annotate.c | 59 +++++++++++++++++++++++++++-------------------
1 file changed, 35 insertions(+), 24 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 273f21f..42b752e 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -19,14 +19,12 @@
#include "evsel.h"
#include "block-range.h"
#include "arch/common.h"
-#include <regex.h>
#include <pthread.h>
#include <linux/bitops.h>
#include <sys/utsname.h>

const char *disassembler_style;
const char *objdump_path;
-static regex_t file_lineno;

static struct ins_ops *ins__find(struct arch *arch, const char *name);
static void ins__sort(struct arch *arch);
@@ -814,7 +812,7 @@ static int disasm_line__parse(char *line, const char **namep, char **rawp)
}

static struct disasm_line *disasm_line__new(s64 offset, char *line,
- size_t privsize, int line_nr,
+ size_t privsize,
struct arch *arch,
struct map *map)
{
@@ -823,7 +821,6 @@ static struct disasm_line *disasm_line__new(s64 offset, char *line,
if (dl != NULL) {
dl->offset = offset;
dl->line = strdup(line);
- dl->line_nr = line_nr;
if (dl->line == NULL)
goto out_delete;

@@ -1121,6 +1118,29 @@ static int disasm_line__print(struct disasm_line *dl, struct symbol *sym, u64 st
return 0;
}

+static int parse_srcline(char *srcline, char **path, int *line_nr)
+{
+ char *sep;
+
+ if (path != NULL)
+ *path = NULL;
+
+ if (!strcmp(srcline, SRCLINE_UNKNOWN))
+ return -1;
+
+ sep = strchr(srcline, ':');
+ if (sep) {
+ *sep = '\0';
+ if (path != NULL)
+ *path = srcline;
+ if (line_nr != NULL)
+ *line_nr = strtoul(++sep, NULL, 0);
+ } else
+ return -1;
+
+ return 0;
+}
+
/*
* symbol__parse_objdump_line() parses objdump output (with -d --no-show-raw)
* which looks like following
@@ -1143,15 +1163,14 @@ static int disasm_line__print(struct disasm_line *dl, struct symbol *sym, u64 st
*/
static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
struct arch *arch,
- FILE *file, size_t privsize,
- int *line_nr)
+ FILE *file, size_t privsize)
{
struct annotation *notes = symbol__annotation(sym);
struct disasm_line *dl;
char *line = NULL, *parsed_line, *tmp, *tmp2, *c;
size_t line_len;
s64 line_ip, offset = -1;
- regmatch_t match[2];
+ bool has_src_code = true;

if (getline(&line, &line_len, file) < 0)
return -1;
@@ -1169,12 +1188,6 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
line_ip = -1;
parsed_line = line;

- /* /filename:linenr ? Save line number and ignore. */
- if (regexec(&file_lineno, line, 2, match, 0) == 0) {
- *line_nr = atoi(line + match[1].rm_so);
- return 0;
- }
-
/*
* Strip leading spaces:
*/
@@ -1205,13 +1218,18 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
parsed_line = tmp2 + 1;
}

- dl = disasm_line__new(offset, parsed_line, privsize, *line_nr, arch, map);
+ dl = disasm_line__new(offset, parsed_line, privsize, arch, map);
free(line);
- (*line_nr)++;

if (dl == NULL)
return -1;

+ if (has_src_code && dl->offset != -1 && map->dso->symsrc_filename) {
+ if (parse_srcline(get_srcline(map->dso, line_ip, NULL, false),
+ NULL, &dl->line_nr) < 0)
+ has_src_code = false;
+ }
+
if (!disasm_line__has_offset(dl)) {
dl->ops.target.offset = dl->ops.target.addr -
map__rip_2objdump(map, sym->start);
@@ -1235,11 +1253,6 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
return 0;
}

-static __attribute__((constructor)) void symbol__init_regexpr(void)
-{
- regcomp(&file_lineno, "^/[^:]+:([0-9]+)", REG_EXTENDED);
-}
-
static void delete_last_nop(struct symbol *sym)
{
struct annotation *notes = symbol__annotation(sym);
@@ -1360,7 +1373,6 @@ int symbol__disassemble(struct symbol *sym, struct map *map, const char *arch_na
struct kcore_extract kce;
bool delete_extract = false;
int stdout_fd[2];
- int lineno = 0;
int nline;
pid_t pid;
int err = dso__disassemble_filename(dso, symfs_filename, sizeof(symfs_filename));
@@ -1435,7 +1447,7 @@ int symbol__disassemble(struct symbol *sym, struct map *map, const char *arch_na
snprintf(command, sizeof(command),
"%s %s%s --start-address=0x%016" PRIx64
" --stop-address=0x%016" PRIx64
- " -l -d %s %s -C %s 2>/dev/null|grep -v %s|expand",
+ " -d %s %s -C %s 2>/dev/null|grep -v %s|expand",
objdump_path ? objdump_path : "objdump",
disassembler_style ? "-M " : "",
disassembler_style ? disassembler_style : "",
@@ -1482,8 +1494,7 @@ int symbol__disassemble(struct symbol *sym, struct map *map, const char *arch_na

nline = 0;
while (!feof(file)) {
- if (symbol__parse_objdump_line(sym, map, arch, file, privsize,
- &lineno) < 0)
+ if (symbol__parse_objdump_line(sym, map, arch, file, privsize) < 0)
break;
nline++;
}
--
2.7.4