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>

tools/perf/builtin-report.c

@@ -812,6 +812,8 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
 
 	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)

tools/perf/builtin-top.c

@@ -1304,6 +1304,9 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 		perf_hpp__cancel_cumulate();
 	}
 
+	if (symbol_conf.cumulate_callchain && !callchain_param.order_set)
+		callchain_param.order = ORDER_CALLER;
+
 	symbol_conf.priv_size = sizeof(struct annotation);
 
 	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);

tools/perf/util/callchain.c

@@ -51,10 +51,12 @@ static int parse_callchain_order(const char *value)
 {
 	if (!strncmp(value, "caller", strlen(value))) {
 		callchain_param.order = ORDER_CALLER;
+		callchain_param.order_set = true;
 		return 0;
 	}
 	if (!strncmp(value, "callee", strlen(value))) {
 		callchain_param.order = ORDER_CALLEE;
+		callchain_param.order_set = true;
 		return 0;
 	}
 	return -1;

tools/perf/util/callchain.h

@@ -75,6 +75,7 @@ struct callchain_param {
 	double			min_percent;
 	sort_chain_func_t	sort;
 	enum chain_order	order;
+	bool			order_set;
 	enum chain_key		key;
 	bool			branch_callstack;
 };

tools/perf/util/util.c

@@ -19,7 +19,7 @@
 struct callchain_param	callchain_param = {
 	.mode	= CHAIN_GRAPH_ABS,
 	.min_percent = 0.5,
-	.order  = ORDER_CALLER,
+	.order  = ORDER_CALLEE,
 	.key	= CCKEY_FUNCTION
 };