From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 401AD397E90 for ; Fri, 13 Mar 2026 15:19:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773415154; cv=none; b=JfVUflSubG2GnEe+X62SHh+nTSR0+94O+wh+TG31fSqJ75Hik3wvzxu09iiic/6K6BW6slGTJGwG8thbdBuQKKOvJyYj3I41gbEIZZs5MxREgaBaZWFILix7dQ/XiUdhDk3oQdTzp2W+KClsKvf0kkvIERRbdGcA6wamHR3NOs0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773415154; c=relaxed/simple; bh=Eh3gjA2sctTF1oNwcOYglGKzXLhEx21cV9/Jjd2sn2w=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Iivm0Z2i8cnFzhDYBW1HK1VGftpSDMfzrRITNVerQtTGmoqeDb87HxL0xIGiY/xGAlma06+xxXagb6BrjIl9GkjQ9S1SScA7ufg19SAR2705FOY5X4Hjj7KAOVwjZiy4kxDvLaiDi7PH0bl5V/bEfbmQo1u7v3jsVI+1WTrvB18= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rEGMi9ls; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rEGMi9ls" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72CE8C19425; Fri, 13 Mar 2026 15:19:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773415153; bh=Eh3gjA2sctTF1oNwcOYglGKzXLhEx21cV9/Jjd2sn2w=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rEGMi9lsYiLQv/vLwjFRgGGjmDMK8E3IXpWOVG+C3Kwze3mTNl8Ic7Bfm04HS0kV5 5QR/MXEe+xEhJBSN48ps492Vm0oc0Hw4evEeiAbghN1DhxcGlwg9fgv+6sdGq8kQAC oNNULQhBQbfbTozChqq1UWyhldF3THh1fi4oTEvJvwHCNslaVxK9zAi80HIT6dcbCm ESZIGQNt6IbyhWvemNaToHT5TKjDlVoTDBjojOAQZWzlpPFtz4KAkkPg5gX6nlFPbD Ud6rHBZicYaa0jbkoROvsf8/9XjK+0c/qrke+Icot0/SiNxE30Ig7v5piXVeqRTRuI 5eRRvZ98UqcHg== Date: Fri, 13 Mar 2026 12:19:11 -0300 From: Arnaldo Carvalho de Melo To: Thomas Richter Cc: Ian Rogers , "linux-perf-use." , Jan Polensky Subject: Re: perf stat issue with 7.0.0rc3 Message-ID: References: <66d0366b-8690-4bde-aba4-1d51f278dfa1@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <66d0366b-8690-4bde-aba4-1d51f278dfa1@linux.ibm.com> On Fri, Mar 13, 2026 at 02:13:18PM +0100, Thomas Richter wrote: > Ian, > > I just discovered a strange behavior on linux 7.0.0rc3. > > I run these commands on my x86 virtual machine: > > bash-5.3# uname -m > x86_64 > bash-5.3# perf -v > perf version 6.18.13-200.fc43.x86_64 > bash-5.3# perf stat -- true > > Performance counter stats for 'true': > > 1.108.929 task-clock # 0,437 CPUs utilized > 0 context-switches # 0,000 /sec > 0 cpu-migrations # 0,000 /sec > 55 page-faults # 49,597 K/sec > cycles > > 0,002536439 seconds time elapsed > > 0,001363000 seconds user > 0,001393000 seconds sys > > bash-5.3# > > This is the epected output, however when I use the perf version 7.0.0rc3: > > bash-5.3# ./perf -v > perf version 7.0.rc3.g1f318b96cc84 > bash-5.3# ./perf stat -- true > Error: > No supported events found. > trace.args_alignment And this last line is even stranger, in my case I get something else, also on x86_64: root@number:~# perf stat -- true Error: No supported events found. addr2line.style root@number:~# On an ARM machine: acme@raspberrypi:~/git/perf-tools $ perf stat -- true Error: No supported events found. acme@raspberrypi:~/git/perf-tools $ uname -a Linux raspberrypi 6.12.62+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.62-1+rpt1 (2025-12-18) aarch64 GNU/Linux acme@raspberrypi:~/git/perf-tools $ I'll try to bisect this later, thanks for the report! - Arnaldo > bash-5.3# > > Same happens on my s390 systems (LPAR and z/VM). > Is this a known already? > I guess this is a perf tool issue, same result when you execute this on a 7.0.0rc3 > kernel. > > Any ideas where to start debugging > -- > Thomas Richter, Dept 3303, IBM s390 Linux Development, Boeblingen, Germany > -- > IBM Deutschland Research & Development GmbH > > Vorsitzender des Aufsichtsrats: Wolfgang Wendt > > Geschäftsführung: David Faller > > Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht Stuttgart, HRB 243294 >