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 8D6DC1ACED2; Fri, 17 Jan 2025 21:02:48 +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=1737147768; cv=none; b=b0SE4M/Q/ZgcJAhvU5ppCtcYYOleo8LpbdPADGZP3+HCQTZgQeazu78xxtInQKF3oDiCR3QISLfsg4F0b9aC+K44VkoiVIo+87+iCHm2R7zZ+1YapTqjMCpoQ59Dy4kKEaW4WCmNluC9VMzqQxSPhegTRcNgpeSrHPrvJvVC9Sk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737147768; c=relaxed/simple; bh=s87ZaprngAbzkyDGjRFuOAMj/B4LIrGPHpa5+JFQka0=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hxRa40fBIa+HhfsbZkh+x65Kx2iaeXQrNYML6WPqut24e4UFt+KILFfFetjyuUV15uqEvXD10VQDfnurh9wrwIO8A+Hf4M2AH3v32beJEZS/UNdUEPtmjiGSffwFjT1JQ2N3qMF/fkJQCO+BoIlEAG6W6jXr8SANxGw3ao1bVVs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53252C4CEDF; Fri, 17 Jan 2025 21:02:47 +0000 (UTC) Date: Fri, 17 Jan 2025 16:02:54 -0500 From: Steven Rostedt To: Tomas Glozar Cc: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, John Kacur , Luis Goncalves , Chang Yin , Qiao Zhao Subject: Re: [PATCH] tools/rtla: Add basic test suite Message-ID: <20250117160254.4a366149@gandalf.local.home> In-Reply-To: References: <20250109133852.360122-1-tglozar@redhat.com> <20250116201808.3c8721c1@gandalf.local.home> 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 On Fri, 17 Jan 2025 11:53:48 +0100 Tomas Glozar wrote: > Maybe after enough time repeating the command I'm also going to hit > the bug you saw. Nevermind. The divide by zero fix went into my tools/urgent branch and I pushed it up to Linus, but I had already started the tools/core branch for the next merge window that I've been adding these patches to. It does not include the fix. The reason for that crash was because of the divide by zero bug. After cherry-picking it for testing, it works. Now, what I also noticed was. When it did crash and die. The osnoise tracer no longer creates any osnoise threads. Can you take a look. Remove the fix, and run that test: ~# echo osnoise > /sys/kernel/tracing/current_tracer ~# ps aux |grep osnois root 942 105 0.0 0 0 ? R 16:00 0:02 [osnoise/0] root 943 104 0.0 0 0 ? R 16:00 0:02 [osnoise/1] root 944 105 0.0 0 0 ? R 16:00 0:02 [osnoise/2] root 945 105 0.0 0 0 ? R 16:00 0:02 [osnoise/3] root 946 105 0.0 0 0 ? R 16:00 0:02 [osnoise/4] root 947 105 0.0 0 0 ? R 16:00 0:02 [osnoise/5] root 948 104 0.0 0 0 ? R 16:00 0:02 [osnoise/6] root 949 130 0.0 0 0 ? R 16:00 0:03 [osnoise/7] root 953 9.0 0.0 6468 2152 pts/0 S+ 16:00 0:00 grep osnois ~# echo nop > /sys/kernel/tracing/current_tracer ~# cd linux.git ~# git show cfff4d019b4c01 | patch -p1 -R ~# cd tools/tracing/rtla/ ~# make ~# ./rtla timerlat hist -i 2 -c 0 -n -d 30s # RTLA timerlat histogram # Time unit is nanoseconds (ns) # Duration: 0 00:00:02 Index IRQ-000 Thr-000 Usr-000 over: 1 0 0 count: 1 0 0 min: 1481365 - - avg: 1481365 - - max: 1481365 - - Floating point exception ~# rmdir /sys/kernel/tracing/instances/timerlat_aa/ ~# rmdir /sys/kernel/tracing/instances/timerlat_hist/ ~# echo osnoise > /sys/kernel/tracing/current_tracer ~# ps aux |grep osnois root 969 11.1 0.0 6468 2244 pts/0 S+ 15:54 0:00 grep osnois So that failure puts the system into a state that can no longer run osnoise. It takes a reboot to fix it. That should be fixed where a reboot is not needed. -- Steve