perf bench mem: The -o and -n options are mutually exclusive

 -o, --only-prefault   Show only the result with page faults before mem*
 -n, --no-prefault     Show only the result without page faults before mem*

Makes no sense to call together. Applies to both memset and memcpy.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1402942467-10671-8-git-send-email-davidlohr@hp.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/bench/mem-memcpy.c

@@ -189,6 +189,11 @@ int bench_mem_memcpy(int argc, const char **argv,
 	argc = parse_options(argc, argv, options,
 			     bench_mem_memcpy_usage, 0);
 
+	if (no_prefault && only_prefault) {
+		fprintf(stderr, "Invalid options: -o and -n are mutually exclusive\n");
+		return 1;
+	}
+
 	if (use_cycle)
 		init_cycle();
 

tools/perf/bench/mem-memset.c

@@ -181,6 +181,11 @@ int bench_mem_memset(int argc, const char **argv,
 	argc = parse_options(argc, argv, options,
 			     bench_mem_memset_usage, 0);
 
+	if (no_prefault && only_prefault) {
+		fprintf(stderr, "Invalid options: -o and -n are mutually exclusive\n");
+		return 1;
+	}
+
 	if (use_cycle)
 		init_cycle();