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 30649361DA6; Fri, 2 Oct 2026 05:44:32 +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=1790919874; cv=none; b=kbmcjxlOc5aI/CEefhR+VsYLmNxSzT4CZMqDxbOqisSzk6HwiAPpCeg7MDava0qG/7PCGGDZDxjRhRCQHfTyvabUX1ouEBO/i8QVIKfOpNSDYkocG7szqT1z6oTAEQvWBtKYpLFcmzOYRx8pCCmr1ZWPR9VFGiCm9r5fiI/hmk4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790919874; c=relaxed/simple; bh=0sTUHdTBguf9D+ODJqdIL5b6eL2ZzSqEDwWf8Ns29CY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=XAc2H15r1WWw8VHeWaTO+sR+1Pp4nQpnvu1ODnLR52wQfwoBLNLWwTbT4K5JD4RhA5gPXJWpFUMXoODcx7b24jLe4MAqSirf4BZDiC8SlOpB5bjUHl8tInf2o1bnZuJXU9c8d7t7ozVerZn9l3IO/WQEfGzD//DGB0pPG+mPE0Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P0vj/5D1; 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="P0vj/5D1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 992551F000FF; Fri, 2 Oct 2026 05:44:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790919872; bh=b7dMkdKwVdOPUbRXbSR/ZpGWRKdnGU2o7/s4+tCrt7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=P0vj/5D1RCIJuoflO9M9xLdRrYHN2zuQaGLnfcHbfjSpKWdYYaBSLA1Vn4m9FpJhD ZARP/MSoNzzOmoOgZHQS8Lsti0/NktOo8bTyRriBT+imeP0XCjBOIBYvICEqUpVcqn LUGmNWeTLBNc9o54aYOI1dvotckHEyi/GaSHeSCSN39HVU5DCvLHn/GerjqoIJxW1W ACzssEsVnijo7krljqe4wrbIp7bqAeuyeofH1TUf5lL6+VP3reCvlFFvcl9UWeFEdm 4GMdaW4bvjw/tvzI9gHcp7cPPTkRw8qHS7j0LmgUa1D4eHFTmUghSAc01/L0tyTmpc peMvXa1psKFjA== 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 v2 2/2] selftests/ftrace: Add test case for overriding trace_instance parameter Date: Fri, 2 Oct 2026 14:44:28 +0900 Message-ID: <179091986836.537422.14557907623051321426.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <179091984881.537422.15308457677039592540.stgit@devnote2> References: <179091984881.537422.15308457677039592540.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