[PATCH V16 6/8] perf: test: Speed up running brstack test on an Arm model

[Anshuman Khandual <anshuman.khandual@arm.com>]

From: James Clark <james.clark@arm.com>

The test runs quite slowly in the model, so replace "xargs -n1" with
"tr ' ' '\n'" which does the same thing but in single digit minutes
instead of double digit minutes.

Also reduce the number of loops in the test application. Unfortunately
this causes intermittent failures on x86, presumably because the
sampling interval is too big to pickup any loops, so keep it the same
there.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: linux-perf-users@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 tools/perf/tests/shell/test_brstack.sh | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/tools/perf/tests/shell/test_brstack.sh b/tools/perf/tests/shell/test_brstack.sh
index 5f14d0cb013f..5ea64d0c4a6f 100755
--- a/tools/perf/tests/shell/test_brstack.sh
+++ b/tools/perf/tests/shell/test_brstack.sh
@@ -18,7 +18,6 @@ fi
 skip_test_missing_symbol brstack_bench
 
 TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
-TESTPROG="perf test -w brstack"
 
 cleanup() {
 	rm -rf $TMPDIR
@@ -26,11 +25,21 @@ cleanup() {
 
 trap cleanup EXIT TERM INT
 
+is_arm64() {
+	uname -m | grep -q aarch64
+}
+
+if is_arm64; then
+	TESTPROG="perf test -w brstack 5000"
+else
+	TESTPROG="perf test -w brstack"
+fi
+
 test_user_branches() {
 	echo "Testing user branch stack sampling"
 
 	perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u -- ${TESTPROG} > /dev/null 2>&1
-	perf script -i $TMPDIR/perf.data --fields brstacksym | xargs -n1 > $TMPDIR/perf.script
+	perf script -i $TMPDIR/perf.data --fields brstacksym | tr ' ' '\n' > $TMPDIR/perf.script
 
 	# example of branch entries:
 	# 	brstack_foo+0x14/brstack_bar+0x40/P/-/-/0/CALL
@@ -59,7 +68,7 @@ test_filter() {
 	echo "Testing branch stack filtering permutation ($test_filter_filter,$test_filter_expect)"
 
 	perf record -o $TMPDIR/perf.data --branch-filter $test_filter_filter,save_type,u -- ${TESTPROG} > /dev/null 2>&1
-	perf script -i $TMPDIR/perf.data --fields brstack | xargs -n1 > $TMPDIR/perf.script
+	perf script -i $TMPDIR/perf.data --fields brstack | tr ' ' '\n' > $TMPDIR/perf.script
 
 	# fail if we find any branch type that doesn't match any of the expected ones
 	# also consider UNKNOWN branch types (-)
-- 
2.25.1