perf buildid-cache: Use strerror_r instead of strerror

Use strerror_r instead of strerror in error messages for thread-safety.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022249.3545.53211.stgit@kbuild-fedora.novalocalSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-buildid-cache.c

@@ -291,6 +291,7 @@ int cmd_buildid_cache(int argc, const char **argv,
 		   *missing_filename = NULL,
 		   *update_name_list_str = NULL,
 		   *kcore_filename;
+	char sbuf[STRERR_BUFSIZE];
 
 	struct perf_data_file file = {
 		.mode  = PERF_DATA_MODE_READ,
@@ -347,7 +348,7 @@ int cmd_buildid_cache(int argc, const char **argv,
 						continue;
 					}
 					pr_warning("Couldn't add %s: %s\n",
-						   pos->s, strerror(errno));
+						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
 				}
 
 			strlist__delete(list);
@@ -365,7 +366,7 @@ int cmd_buildid_cache(int argc, const char **argv,
 						continue;
 					}
 					pr_warning("Couldn't remove %s: %s\n",
-						   pos->s, strerror(errno));
+						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
 				}
 
 			strlist__delete(list);
@@ -386,7 +387,7 @@ int cmd_buildid_cache(int argc, const char **argv,
 						continue;
 					}
 					pr_warning("Couldn't update %s: %s\n",
-						   pos->s, strerror(errno));
+						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
 				}
 
 			strlist__delete(list);