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perf probe: Fix to show lines of sys_ functions correctly

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"perf probe --lines sys_poll" shows only the first line of sys_poll,
because the SYSCALL_DEFINE macro:

  ----
  SYSCALL_DEFINE*(foo,...)
  {
    body;
  }
  ----

  is expanded as below (on debuginfo)

  ----

  static inline int SYSC_foo(...)
  {
    body;
  }
  int SyS_foo(...) <- is an alias of sys_foo.
  {
    return SYSC_foo(...);
  }
  ----

So, "perf probe --lines sys_foo" decodes SyS_foo function and it also skips
inlined functions(SYSC_foo) inside the target function because those functions
are usually defined somewhere else.

To fix this issue, this fix checks whether the inlined function is defined at
the same point of the target function, and if so, it doesn't skip the inline
function.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150812012406.11811.94691.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Masami Hiramatsu 2015-08-12 10:24:07 +09:00 committed by Arnaldo Carvalho de Melo
parent 63ab1749f3
commit 75186a9b09
1 changed files with 13 additions and 5 deletions
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18
tools/perf/util/dwarf-aux.c
View file

@ -734,15 +734,18 @@ int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data)
Dwarf_Lines *lines;
Dwarf_Line *line;
Dwarf_Addr addr;
const char *fname;
const char *fname, *decf = NULL;
int lineno, ret = 0;
int decl = 0, inl;
Dwarf_Die die_mem, *cu_die;
size_t nlines, i;
/* Get the CU die */
if (dwarf_tag(rt_die) != DW_TAG_compile_unit)
if (dwarf_tag(rt_die) != DW_TAG_compile_unit) {
cu_die = dwarf_diecu(rt_die, &die_mem, NULL, NULL);
else
dwarf_decl_line(rt_die, &decl);
decf = dwarf_decl_file(rt_die);
} else
cu_die = rt_die;
if (!cu_die) {
pr_debug2("Failed to get CU from given DIE.\n");
@ -773,9 +776,14 @@ int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data)
* The line is included in given function, and
* no inline block includes it.
*/
if (!dwarf_haspc(rt_die, addr) ||
die_find_inlinefunc(rt_die, addr, &die_mem))
if (!dwarf_haspc(rt_die, addr))
continue;
if (die_find_inlinefunc(rt_die, addr, &die_mem)) {
dwarf_decl_line(&die_mem, &inl);
if (inl != decl ||
decf != dwarf_decl_file(&die_mem))
continue;
}
/* Get source line */
fname = dwarf_linesrc(line, NULL, NULL);