[PATCH 4.9 57/84] perf probe: Fix --funcs to show correct symbols for offline module

Greg Kroah-Hartman
2017-08-28T08:13:42Z

From: Masami Hiramatsu <mhiramat@kernel.org>

commit eebc509b20881b92d62e317b2c073e57c5f200f0 upstream.

Fix --funcs (-F) option to show correct symbols for offline module.
Since previous perf-probe uses machine__findnew_module_map() for offline
module, even if user passes a module file (with full path) which is for
other architecture, perf-probe always tries to load symbol map for
current kernel module.

This fix uses dso__new_map() to load the map from given binary as same
as a map for user applications.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148350053478.19001.15435255244512631545.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
tools/perf/util/probe-event.c | 25 ++++++-------------------
1 file changed, 6 insertions(+), 19 deletions(-)

--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -163,7 +163,7 @@ static struct map *kernel_get_module_map

/* A file path -- this is an offline module */
if (module && strchr(module, '/'))
- return machine__findnew_module_map(host_machine, 0, module);
+ return dso__new_map(module);

if (!module)
module = "kernel";
@@ -173,6 +173,7 @@ static struct map *kernel_get_module_map
if (strncmp(pos->dso->short_name + 1, module,
pos->dso->short_name_len - 2) == 0 &&
module[pos->dso->short_name_len - 2] == '\0') {
+ map__get(pos);
return pos;
}
}
@@ -188,15 +189,6 @@ struct map *get_target_map(const char *t
return kernel_get_module_map(target);
}

-static void put_target_map(struct map *map, bool user)
-{
- if (map && user) {
- /* Only the user map needs to be released */
- map__put(map);
- }
-}
-
-
static int convert_exec_to_group(const char *exec, char **result)
{
char *ptr1, *ptr2, *exec_copy;
@@ -412,7 +404,7 @@ static int find_alternative_probe_point(
}

out:
- put_target_map(map, uprobes);
+ map__put(map);
return ret;

}
@@ -2944,7 +2936,7 @@ static int find_probe_trace_events_from_
}

out:
- put_target_map(map, pev->uprobes);
+ map__put(map);
free(syms);
return ret;

@@ -3437,10 +3429,7 @@ int show_available_funcs(const char *tar
return ret;

/* Get a symbol map */
- if (user)
- map = dso__new_map(target);
- else
- map = kernel_get_module_map(target);
+ map = get_target_map(target, user);
if (!map) {
pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
return -EINVAL;
@@ -3472,9 +3461,7 @@ int show_available_funcs(const char *tar
}

end:
- if (user) {
- map__put(map);
- }
+ map__put(map);
exit_probe_symbol_maps();

return ret;