From: James Clark <james.clark@linaro.org>
Date: Tue, 9 Jun 2026 14:40:11 +0000 (+0100)
Subject: perf test cs-etm: Replace unroll loop thread with deterministic decode test
X-Git-Url: http://git.ipfire.org/index.cgi?a=commitdiff_plain;h=ccf62a267a660cbc2c5ca0208a94fee4ef256926;p=thirdparty%2Fkernel%2Flinux.git

perf test cs-etm: Replace unroll loop thread with deterministic decode test

Testing a long sequence without branches seems like it would be better
as a decoder unit test, and this test doesn't test decoding either, so
it's not clear what bugs this is trying to catch.

The new deterministic workload has somewhat long sequences when built
unoptimized, and we can always increase them later if we want to. But
now we test that decoding always gives the same result for the same
sequence of code which we've never had before.

Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Leo Yan <leo.yan@arm.com>
Cc: Amir Ayupov <aaupov@meta.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paschalis Mpeis <Paschalis.Mpeis@arm.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/tests/shell/coresight/deterministic.sh b/tools/perf/tests/shell/coresight/deterministic.sh
new file mode 100755
index 0000000000000..75d4973056f0d
--- /dev/null
+++ b/tools/perf/tests/shell/coresight/deterministic.sh
@@ -0,0 +1,72 @@
+#!/bin/bash -e
+# CoreSight deterministic workload decode (exclusive)
+
+# SPDX-License-Identifier: GPL-2.0
+
+# If CoreSight is not available, skip the test
+perf list pmu | grep -q cs_etm || exit 2
+
+tmpdir=$(mktemp -d /tmp/__perf_test.coresight_deterministic.XXXXX)
+
+cleanup() {
+	rm -rf "${tmpdir}"
+	trap - EXIT TERM INT
+}
+
+trap_cleanup() {
+	cleanup
+	exit 1
+}
+trap trap_cleanup EXIT TERM INT
+
+cf="$tmpdir/ctl"
+af="$tmpdir/ack"
+mkfifo "$cf" "$af"
+
+# Start disabled and use the control FIFO to only record the workload and not
+# startup.
+perf record -o "$tmpdir/data" -e cs_etm//u -D -1 --control fifo:"$cf","$af" -- \
+	perf test --record-ctl fifo:"$cf","$af" -w deterministic > /dev/null 2>&1
+
+perf script -i "$tmpdir/data" --itrace=i1i -F ip,srcline | \
+	grep "deterministic.c" | uniq > "$tmpdir/script" 2>/dev/null
+
+
+# Remove brace lines and call sites as they may not be hit or may have
+# extra hits after returning, depending on the compiler.
+sed -i \
+  -e '/deterministic.c:8$/d' \
+  -e '/deterministic.c:12$/d' \
+  -e '/deterministic.c:15$/d' \
+  -e '/deterministic.c:19$/d' \
+  -e '/deterministic.c:23$/d' \
+  -e '/deterministic.c:28$/d' \
+  -e '/deterministic.c:34$/d' \
+  -e '/deterministic.c:36$/d' \
+  -e '/deterministic.c:37$/d' \
+  "$tmpdir/script"
+
+cat > "$tmpdir/expected" << EOF
+  deterministic.c:24
+  deterministic.c:25
+  deterministic.c:26
+  deterministic.c:9
+  deterministic.c:10
+  deterministic.c:11
+  deterministic.c:30
+  deterministic.c:31
+  deterministic.c:32
+  deterministic.c:16
+  deterministic.c:17
+  deterministic.c:18
+EOF
+
+if ! diff -q "$tmpdir/script" "$tmpdir/expected"; then
+	echo "FAIL: line numbers don't match expected: "
+	head -n 100 "$tmpdir/script"
+	cleanup
+	exit 1
+fi
+
+cleanup
+exit 0
diff --git a/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh b/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh
deleted file mode 100755
index cb3e97a0a89f3..0000000000000
--- a/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/bin/bash -e
-# CoreSight / Unroll Loop Thread 10 (exclusive)
-
-# SPDX-License-Identifier: GPL-2.0
-# Carsten Haitzler <carsten.haitzler@arm.com>, 2021
-
-TEST="unroll_loop_thread"
-
-# shellcheck source=../lib/coresight.sh
-. "$(dirname $0)"/../lib/coresight.sh
-
-ARGS="10"
-DATV="10"
-# shellcheck disable=SC2153
-DATA="$DATD/perf-$TEST-$DATV.data"
-
-perf record $PERFRECOPT -o "$DATA" "$BIN" $ARGS
-
-perf_dump_aux_verify "$DATA" 10 10 10
-
-err=$?
-exit $err