perf probe: Fix to probe an inline function which has no entry pc

BugLink: https://bugs.launchpad.net/bugs/1859712
[ Upstream commit eb6933b29d20bf2c3053883d409a53f462c1a3ac ]

Fix perf probe to probe an inlne function which has no entry pc
or low pc but only has ranges attribute.

This seems very rare case, but I could find a few examples, as
same as probe_point_search_cb(), use die_entrypc() to get the
entry address in probe_point_inline_cb() too.

Without this patch:

  # perf probe -D __amd_put_nb_event_constraints
  Failed to get entry address of __amd_put_nb_event_constraints.
  Probe point '__amd_put_nb_event_constraints' not found.
    Error: Failed to add events.

With this patch:

  # perf probe -D __amd_put_nb_event_constraints
  p:probe/__amd_put_nb_event_constraints amd_put_event_constraints+43

Committer testing:

Before:

  [root@quaco ~]# perf probe -D __amd_put_nb_event_constraints
  Failed to get entry address of __amd_put_nb_event_constraints.
  Probe point '__amd_put_nb_event_constraints' not found.
    Error: Failed to add events.
  [root@quaco ~]#

After:

  [root@quaco ~]# perf probe -D __amd_put_nb_event_constraints
  p:probe/__amd_put_nb_event_constraints _text+33789
  [root@quaco ~]#

Fixes: 4ea42b181434 ("perf: Add perf probe subcommand, a kprobe-event setup helper")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199320336.8075.16189530425277588587.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 5fee71e960a61d3e72eb9f80c380f631bc40c027..b06b05bd488e2c4a402cf6997ab44d4e5cfa0caa 100644 (file)
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -953,7 +953,7 @@ static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
                ret = find_probe_point_lazy(in_die, pf);
        else {
                /* Get probe address */
-               if (dwarf_entrypc(in_die, &addr) != 0) {
+               if (die_entrypc(in_die, &addr) != 0) {
                        pr_warning("Failed to get entry address of %s.\n",
                                   dwarf_diename(in_die));
                        return -ENOENT;