From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B75F3344DB7; Sat, 19 Sep 2026 14:38:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789828723; cv=none; b=rYjc4OR/BlzC952CCuoShru45zk235ta3U1DVbZUavEGbVa83UuyRQReGUkFfcKf86lGYwTq4kzCwTFA4OKxRVte9cJfemRyHDmvGTvlH+E3SCQ8GyCocfX0Nw22W/gjrDBjR2QW02PDeCpt3xUJwErwmEjWeaZV1KIW6U2M2Dg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789828723; c=relaxed/simple; bh=0sTUHdTBguf9D+ODJqdIL5b6eL2ZzSqEDwWf8Ns29CY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=QzXqhW5tS2qTsJ8VDrHKgs8JuFc4zkALSiHXnjwPaO345rd6xCDGVl3+CouNtXoe1Zvojjg0rUSKQyq9GUDQB6Ts5HpkcszTUVGhtyspFNDemO+n4FPfwGk4b7ZaaVJgd4g0H71a9tffF48+0fkOFEUMD+gVxgUqV3G2q+QnjUk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eiVEdh/z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eiVEdh/z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 327E11F000FF; Sat, 19 Sep 2026 14:38:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789828721; bh=b7dMkdKwVdOPUbRXbSR/ZpGWRKdnGU2o7/s4+tCrt7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eiVEdh/z+DIpaYbhrF/Sf96pO066THwbfh3exO7y6wf9CvboZaTpuRsJcQoAsZje+ EwscWzfRg0/jrBO4Ey2G8SmLpEaaFw/MKP04Tjeoo8M5+nSAZhYffTv5LgKktvr1WH wLQb0fF+BLMCQAcI+7b0b7gdk4QE6hxoLxcoZbEFrWuU5YFrphzrQBfm8nYfHUvumv eqXneLzfMmbOBz25nd/9Gt18iHULw7xN2tj3rHFK2gz6oInmBWfo4iasoQSbsmKNXx ukyjSuie9mpbrVxXHdquQ2h0ZiHisy4wtr1+gihTMidmTxGyNowjs9JYlZSfVaJBkU XMrp3lwlD/o9Q== From: "Masami Hiramatsu (Google)" To: Jonathan Corbet , Steven Rostedt , Masami Hiramatsu , Shuah Khan Cc: Shuah Khan , Mathieu Desnoyers , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH 2/2] selftests/ftrace: Add test case for overriding trace_instance parameter Date: Sat, 19 Sep 2026 23:38:36 +0900 Message-ID: <178982871684.289221.11881705926508561494.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <178982869661.289221.2143320719673148321.stgit@devnote2> References: <178982869661.289221.2143320719673148321.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit From: Masami Hiramatsu (Google) Add a boot-time tracing test case to verify that specifying multiple trace_instance= parameters with the same instance name overrides earlier definitions: - Verifies that a kernel command-line trace_instance= parameter overrides an earlier trace instance defined via bootconfig (kernel.trace_instance). - Verifies that a latter kernel command-line trace_instance= parameter overrides an earlier trace_instance= on the same command line. - Confirms that the overridden instance has its previous events disabled, new events enabled, and flags (such as traceoff) properly applied. Assisted-by: Antigravity:gemini-3.8-flash Signed-off-by: Masami Hiramatsu (Google) --- .../cmdline-07-trace-instance-override.bconf | 2 + .../cmdline-07-trace-instance-override.cmdline | 1 .../tests/cmdline-07-trace-instance-override.sh | 56 ++++++++++++++++++++ 3 files changed, 59 insertions(+) create mode 100644 tools/testing/selftests/ftrace/boottime/bootconfigs/cmdline-07-trace-instance-override.bconf create mode 100644 tools/testing/selftests/ftrace/boottime/cmdlines/cmdline-07-trace-instance-override.cmdline create mode 100644 tools/testing/selftests/ftrace/boottime/tests/cmdline-07-trace-instance-override.sh diff --git a/tools/testing/selftests/ftrace/boottime/bootconfigs/cmdline-07-trace-instance-override.bconf b/tools/testing/selftests/ftrace/boottime/bootconfigs/cmdline-07-trace-instance-override.bconf new file mode 100644 index 000000000000..2551da39f722 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/bootconfigs/cmdline-07-trace-instance-override.bconf @@ -0,0 +1,2 @@ +kernel.trace_instance = "foo,sched:sched_switch" + diff --git a/tools/testing/selftests/ftrace/boottime/cmdlines/cmdline-07-trace-instance-override.cmdline b/tools/testing/selftests/ftrace/boottime/cmdlines/cmdline-07-trace-instance-override.cmdline new file mode 100644 index 000000000000..1953eb5d6f80 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/cmdlines/cmdline-07-trace-instance-override.cmdline @@ -0,0 +1 @@ +trace_instance=foo^traceoff,sched:sched_waking trace_instance=bar,sched:sched_switch trace_instance=bar^traceoff,irq:irq_handler_entry diff --git a/tools/testing/selftests/ftrace/boottime/tests/cmdline-07-trace-instance-override.sh b/tools/testing/selftests/ftrace/boottime/tests/cmdline-07-trace-instance-override.sh new file mode 100644 index 000000000000..a13b7deb6735 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/tests/cmdline-07-trace-instance-override.sh @@ -0,0 +1,56 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2026, Google LLC. +# Check trace_instance= override with bootconfig and kernel command-line +TRACEDIR="/sys/kernel/tracing" + +if [ -f /proc/bootconfig ] && grep -q "dump_bconf" /proc/cmdline 2>/dev/null; then + echo "=== /proc/bootconfig ===" + cat /proc/bootconfig + echo "========================" +fi + +check_instance() { + instance="$1" + old_event="$2" + new_event="$3" + + if [ ! -d "$TRACEDIR/instances/$instance" ]; then + echo "FAIL: trace instance $instance does not exist" + exit 1 + fi + + if [ -f "$TRACEDIR/instances/$instance/events/$old_event/enable" ]; then + ENABLE=$(cat "$TRACEDIR/instances/$instance/events/$old_event/enable") + if [ "$ENABLE" = "1" ]; then + echo "FAIL: overridden event $old_event is still enabled in instance $instance" + exit 1 + fi + fi + + if [ ! -d "$TRACEDIR/instances/$instance/events/$new_event" ]; then + echo "FAIL: event $new_event does not exist in instance $instance" + exit 1 + fi + + ENABLE=$(cat "$TRACEDIR/instances/$instance/events/$new_event/enable") + if [ "$ENABLE" != "1" ]; then + echo "FAIL: event $new_event is not enabled in instance $instance ($ENABLE)" + exit 1 + fi + + TRACING_ON=$(cat "$TRACEDIR/instances/$instance/tracing_on") + if [ "$TRACING_ON" != "0" ]; then + echo "FAIL: tracing_on is not 0 in instance $instance ($TRACING_ON)" + exit 1 + fi +} + +# Test 1: bootconfig trace_instance overridden by cmdline parameter +check_instance "foo" "sched/sched_switch" "sched/sched_waking" + +# Test 2: cmdline trace_instance overridden by subsequent cmdline parameter +check_instance "bar" "sched/sched_switch" "irq/irq_handler_entry" + +echo "PASS: cmdline-07-trace-instance-override" +exit 0