perf util: Hint missing file when tool tips fail to load

Besides memory allocation failure, tips.txt may fail to load because the
file is not found (a more likely cause).

Communicate that to the user in tips failure warning.
Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170412064919.92449-5-davidcc@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/util.c

@@ -696,7 +696,8 @@ const char *perf_tip(const char *dirpath)
 
 	tips = strlist__new("tips.txt", &conf);
 	if (tips == NULL)
-		return errno == ENOENT ? NULL : "Tip: get more memory! ;-p";
+		return errno == ENOENT ? NULL :
+			"Tip: check path of tips.txt or get more memory! ;-p";
 
 	if (strlist__nr_entries(tips) == 0)
 		goto out;