From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) (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 0A79C3168E8; Thu, 29 Jan 2026 17:05:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769706320; cv=none; b=hVm/PvLFJQ+mWTzuM8uUbVSW1acwC2HmUHZ5gN9gN7RAIcWTk8X8PZ36D6NLm7CFGoQnFUTsLFmGsBfduuhlprqtzVKfxW0K6ZAiVMMfxJBeEDR9e1vXlvR9HzYAopU2Ek4v6FZQUP9T13pqOuGoNUioojlgk6P+LlFfMAByDhE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769706320; c=relaxed/simple; bh=4ZVWEeoRYiyQeROefWmDzEV1Ldxeg+QgF2VlnxTOXPE=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ufu3yzqCVlWAHSCg5GTzecUUN8l9o8BFZWGaVyQ91a4qTeitPFhWrn40Rc5bkdDvXyoS/IHWCuxe1vssdaTuBALlwg/3CfabeBwnbsBLGsIpm7mQtadDkVx85cgemHvUJet7DlF2DKwpy2rAEp5+5d4tfeqK9rS9AKPd65/4v7Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 2F91C160201; Thu, 29 Jan 2026 17:05:15 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf03.hostedemail.com (Postfix) with ESMTPA id 3B01F60015; Thu, 29 Jan 2026 17:05:11 +0000 (UTC) Date: Thu, 29 Jan 2026 12:05:23 -0500 From: Steven Rostedt To: Vincent Donnefort Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, aneesh.kumar@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org, Shuah Khan , linux-kselftest@vger.kernel.org Subject: Re: [PATCH v10 15/30] tracing: selftests: Add trace remote tests Message-ID: <20260129120523.6f710ff2@gandalf.local.home> In-Reply-To: <20260126104419.1649811-16-vdonnefort@google.com> References: <20260126104419.1649811-1-vdonnefort@google.com> <20260126104419.1649811-16-vdonnefort@google.com> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: txaufewkoqfauzwkqo47d1diq43oa8q6 X-Rspamd-Server: rspamout04 X-Rspamd-Queue-Id: 3B01F60015 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18BLc+YPC0Jad8q2qNeGSamiSkist3+hCI= X-HE-Tag: 1769706311-773773 X-HE-Meta: U2FsdGVkX18Gk3kh6frTDRcDF0tQBXJ5dAmTOR263lq+mjgXcTAeLPXIei7FJ5BLztwLyBZ/hXl6282qf0MCx78WPvPe6Vd4hZ3PIYWs6aqPUk1zQHysAjLvy4PWfu9AeXLPj38m+I10sjlarN3a00PXUnFHJQX9Q5MOyImib//LQL1kI1ciw/GzqcOaBk2/HzpZTDnPxlrZDG7PqfRupWk7RJJOnqpfIpvAYNheYH44ACfHOpDFCvHEcSneqDvufOY14MT9W85629RcnJB2zXRvyjpWX8pd2/sGCkiPOBZ95Fpdlj71kk3Dw7E0oTWaWmKgQWyBEGEXGb1i0qEJModXvjth6QWh On Mon, 26 Jan 2026 10:44:04 +0000 Vincent Donnefort wrote: > --- /dev/null > +++ b/tools/testing/selftests/ftrace/test.d/remotes/trace.tc > @@ -0,0 +1,127 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > +# description: Test trace remote non-consuming read > +# requires: remotes/test > + > +. $TEST_DIR/remotes/functions > + > +test_trace() > +{ > + echo 0 > tracing_on > + assert_unloaded > + > + echo 7 > buffer_size_kb > + echo 1 > tracing_on > + assert_loaded > + > + # Simple test: Emit few events and try to read them > + for i in $(seq 1 8); do > + echo $i > write_event > + done > + > + check_trace 1 8 trace > + > + # > + # Test interaction with consuming read > + # > + > + cat trace_pipe > /dev/null & > + pid=$! > + > + sleep 1 > + kill $pid > + > + test $(wc -l < trace) -eq 0 > + > + for i in $(seq 16 32); do > + echo $i > write_event > + done > + > + check_trace 16 32 trace > + > + # > + # Test interaction with reset > + # > + > + echo 0 > trace > + > + test $(wc -l < trace) -eq 0 > + > + for i in $(seq 1 8); do > + echo $i > write_event > + done > + > + check_trace 1 8 trace > + > + # > + # Test interaction with lost events > + # > + > + # Ensure the writer is not on the reader page by reloading the buffer > + echo 0 > tracing_on > + echo 0 > trace > + assert_unloaded > + echo 1 > tracing_on > + assert_loaded > + > + # Ensure ring-buffer overflow by emitting events from the same CPU > + for cpu in $(get_cpu_ids); do > + break > + done > + > + events_per_page=$(($(get_page_size) / $(get_selftest_event_size))) # Approx: does not take TS into account > + nr_events=$(($events_per_page * 2)) > + for i in $(seq 1 $nr_events); do > + taskset -c $cpu echo $i > write_event > + done > + > + id=$(sed -n -e '1s/\[[0-9]*\]\s*[0-9]*.[0-9]*: [a-z]* id=\([0-9]*\)/\1/p' trace) > + test $id -ne 1 > + > + check_trace $id $nr_events trace > + > + # > + # Test per-CPU interface > + # > + echo 0 > trace > + > + for cpu in $(get_cpu_ids) ; do > + taskset -c $cpu echo $cpu > write_event > + done > + > + for cpu in $(get_cpu_ids); do > + cd per_cpu/cpu$cpu/ > + > + check_trace $cpu $cpu trace > + > + cd - > /dev/null > + done > + > + # > + # Test with hotplug > + # > + > + [ "$(get_cpu_ids | wc -l)" -ge 2 ] || return 0 > + > + echo 0 > trace > + > + for cpu in $(get_cpu_ids); do > + echo 0 > /sys/devices/system/cpu/cpu$cpu/online Note, my test VM doesn't have cpu0/online, so this needs to test for the existence of these files: ./ftracetest: 105: /work/git/linux.git/tools/testing/selftests/ftrace/test.d/remotes/trace_pipe.tc: cannot create /sys/devices/system/cpu/cpu0/online: Permission denied -- Steve > + break > + done > + > + for i in $(seq 1 8); do > + echo $i > write_event > + done > + > + check_trace 1 8 trace > + > + echo 1 > /sys/devices/system/cpu/cpu$cpu/online > +} > + > +if [ -z "$SOURCE_REMOTE_TEST" ]; then > + set -e > + > + setup_remote_test > + test_trace > +fi