perf tools: Defaults to 'caller' callchain order only if --children is enabled

The caller callchain order is useful with --children option since it can
show 'overview' style output, but other commands which don't use
--children feature like 'perf script' or even 'perf report/top' without
--children are better to keep callee order.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445499946-29817-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 18a8c52..545c51c 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -812,6 +812,8 @@
 
 	if (report.inverted_callchain)
 		callchain_param.order = ORDER_CALLER;
+	if (symbol_conf.cumulate_callchain && !callchain_param.order_set)
+		callchain_param.order = ORDER_CALLER;
 
 	if (itrace_synth_opts.callchain &&
 	    (int)itrace_synth_opts.callchain_sz > report.max_stack)