[PATCH -tip 4/4] perf/probe: Improve error messages with --line option

[Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>]

Improve error messages of perf probe --line mode. Current
perf probe shows "Debuginfo analysis failed" error with an
error code when the given symbol is not found as below.

  -----
  # perf probe -L page_cgroup_init_flatmem
  Debuginfo analysis failed. (-2)
    Error: Failed to show lines.
  -----

But -2 (-ENOMEM) means that the given source line or function
is not found. With this patch, perf probe shows correct error
message as below.

  -----
  # perf probe -L page_cgroup_init_flatmem
  Specified source line is not found.
    Error: Failed to show lines.
  -----

There is also another debug error code is shown in the same
function after get_real_path(). This removes that too.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
---
 tools/perf/util/probe-event.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 44c7141..9a0a183 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -628,11 +628,11 @@ static int __show_line_range(struct line_range *lr, const char *module)
 
 	ret = debuginfo__find_line_range(dinfo, lr);
 	debuginfo__delete(dinfo);
-	if (ret == 0) {
+	if (ret == 0 || ret == -ENOENT) {
 		pr_warning("Specified source line is not found.\n");
 		return -ENOENT;
 	} else if (ret < 0) {
-		pr_warning("Debuginfo analysis failed. (%d)\n", ret);
+		pr_warning("Debuginfo analysis failed.\n");
 		return ret;
 	}
 
@@ -641,7 +641,7 @@ static int __show_line_range(struct line_range *lr, const char *module)
 	ret = get_real_path(tmp, lr->comp_dir, &lr->path);
 	free(tmp);	/* Free old path */
 	if (ret < 0) {
-		pr_warning("Failed to find source file. (%d)\n", ret);
+		pr_warning("Failed to find source file path.\n");
 		return ret;
 	}