[RFC/PATCH 3/3] perf tools: Defaults to 'caller' callchain order only if --children is enabled

[Namhyung Kim <namhyung@kernel.org>]

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 caller order.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-report.c | 2 ++
 tools/perf/builtin-top.c    | 3 +++
 tools/perf/util/callchain.c | 2 ++
 tools/perf/util/callchain.h | 1 +
 tools/perf/util/util.c      | 2 +-
 5 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 18a8c52d921e..545c51cef7f7 100644
--- a/tools/perf/builtin-report.c
+++ b/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)
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1de381d3f29f..af849b1d7389 100644
--- a/tools/perf/builtin-top.c
+++ b/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);
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 842be32899ee..735ad48e1858 100644
--- a/tools/perf/util/callchain.c
+++ b/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;
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 836d59a001bc..aaf467c9ef2b 100644
--- a/tools/perf/util/callchain.h
+++ b/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;
 };
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index c1bf9ff210b0..cd12c25e4ea4 100644
--- a/tools/perf/util/util.c
+++ b/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
 };
 
-- 
2.6.0