[PATCH] perf buildid-cache: Warn --purge-all failures

[Ravi Bangoria]

Warn perf buildid-cache --purge-all failures in non verbose mode.
Ex,

  $ sudo chown root:root /home/ravi/.debug -R
  $ ./perf buildid-cache -P
    Error: Permission denied.

Suggested-by: Masami Hiramatsu <mhira...@kernel.org>
Signed-off-by: Ravi Bangoria <ravi.bango...@linux.ibm.com>
---
 tools/perf/builtin-buildid-cache.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-buildid-cache.c 
b/tools/perf/builtin-buildid-cache.c
index 7a7403913b57..ef6b3cc8d57d 100644
--- a/tools/perf/builtin-buildid-cache.c
+++ b/tools/perf/builtin-buildid-cache.c
@@ -488,8 +488,12 @@ int cmd_buildid_cache(int argc, const char **argv)
                }
        }
 
-       if (purge_all)
-               ret = build_id_cache__purge_all();
+       if (purge_all) {
+               if (build_id_cache__purge_all()) {
+                       pr_warning("Error: %s.\n",
+                               str_error_r(errno, sbuf, sizeof(sbuf)));
+               }
+       }
 
        if (missing_filename)
                ret = build_id_cache__fprintf_missing(session, stdout);
-- 
2.14.3