perf tests: Fix hist accumulation test

User's values from .perfconfig could overload the default callchain
setup and cause this test to fail.  Making sure the test is using
default callchain_param values.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1467634583-29147-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/hists_cumulate.c

@@ -216,6 +216,8 @@ static int do_test(struct hists *hists, struct result *expected, size_t nr_expec
 
 		/* check callchain entries */
 		root = &he->callchain->node.rb_root;
+
+		TEST_ASSERT_VAL("callchains expected", !RB_EMPTY_ROOT(root));
 		cnode = rb_entry(rb_first(root), struct callchain_node, rb_node);
 
 		c = 0;
@@ -666,6 +668,8 @@ static int test4(struct perf_evsel *evsel, struct machine *machine)
 	perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 
 	setup_sorting(NULL);
+
+	callchain_param = callchain_param_default;
 	callchain_register_param(&callchain_param);
 
 	err = add_hist_entries(hists, machine);

tools/perf/util/callchain.h

@@ -106,6 +106,7 @@ struct callchain_param {
 };
 
 extern struct callchain_param callchain_param;
+extern struct callchain_param callchain_param_default;
 
 struct callchain_list {
 	u64			ip;

tools/perf/util/util.c

@@ -19,12 +19,19 @@
 #include "callchain.h"
 #include "strlist.h"
 
-struct callchain_param	callchain_param = {
-	.mode	= CHAIN_GRAPH_ABS,
-	.min_percent = 0.5,
-	.order  = ORDER_CALLEE,
-	.key	= CCKEY_FUNCTION,
-	.value	= CCVAL_PERCENT,
+#define CALLCHAIN_PARAM_DEFAULT			\
+	.mode		= CHAIN_GRAPH_ABS,	\
+	.min_percent	= 0.5,			\
+	.order		= ORDER_CALLEE,		\
+	.key		= CCKEY_FUNCTION,	\
+	.value		= CCVAL_PERCENT,	\
+
+struct callchain_param callchain_param = {
+	CALLCHAIN_PARAM_DEFAULT
+};
+
+struct callchain_param callchain_param_default = {
+	CALLCHAIN_PARAM_DEFAULT
 };
 
 /*