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 C06EA1CB301; Thu, 10 Oct 2024 14:48:24 +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=1728571704; cv=none; b=oIXE9HiX0pWE1r7EVeGAUVTNn4tVg5aFDuCHqCNfPHgXODf5TSOzoo/kZABfZjUWkApXMy88xNiiYonI/zA2NfpNslmhfJrklmefyCLaJK2uKQKgkYCWHP3xcYVkRaDuwu8wrUNNFOS3rg/yRp1Zp01EyTPU8STV008AKiA9NpM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728571704; c=relaxed/simple; bh=zihjJSEgqk+803gp0qkrmkT2DT2099l3r+BnmjzK/z8=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=FYKUUvid1pvultWmZEg12HfSDW1SFrFLJh6i7AqPvVZY8uyYNAS8R0DeLTxdWSDJ0QchBaLU4OErYOiNTh/l9DD+q6JF+JavHJ3PlTg32/lY77KF9eqUCAsGSWWnc+aw5cwX/hj2qTFMPRzg+jhvH/KEyHYWdA3kNvrjXa3ang4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=p93GkPmB; 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="p93GkPmB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2FABC4CEC5; Thu, 10 Oct 2024 14:48:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728571704; bh=zihjJSEgqk+803gp0qkrmkT2DT2099l3r+BnmjzK/z8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=p93GkPmB0lxl8MtDh/ktV50083tvRB8hL0IcuFvZOQzmPpwQ4knf8aNcHAbP2+IFe YUAJje7LUFTOdti6ZOADgYj8ROrE+O3Qv4Vk91kRrz3yMHDnzT0iihP10OU6KDoygc Fb008JGYpZrlikPDqyD+c2qROY1mTv5OCtaiJu751xo5hZkMIQ6EB4Mx5hQ0+FaSnr kc79Daa6XFdW/93eSrtyXQpikrXgMtnqxKTD2M8o+BXWcLBwlx2Sc3rTHc7hDV2a+9 EOeuS1f8l+7cXOdtY2jpsviXGLf1T8Kdn2EkNDuA/JHvJXZWL2D30Hny6PRrHc3rkA CHi+/niiayyzg== Date: Thu, 10 Oct 2024 23:48:18 +0900 From: Masami Hiramatsu (Google) To: Namhyung Kim Cc: Leo Yan , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , Dima Kogan , james.clark@linaro.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 0/3] perf probe: Support long symbol Message-Id: <20241010234818.ab279974ef597f02b61ab850@kernel.org> In-Reply-To: References: <20241007141116.882450-1-leo.yan@arm.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 9 Oct 2024 18:12:52 -0700 Namhyung Kim wrote: > Hello Leo, > > On Mon, Oct 07, 2024 at 03:11:13PM +0100, Leo Yan wrote: > > Currently, a probe supports event name maximum to a 64-byte length. The > > event name comes from the probed symbol name, otherwise, user can > > specify an event name. > > > > In the case when user tries to inject a probe for a long symbol, e.g. > > mangled symbol name in a C++ program, the kernel buffer cannot > > accommodate it if the symbol name is longer than 64 bytes. > > > > On the other hand, this series relies on the perf tool to resolve the > > issue. When the tool detects user doesn't specify event name and the > > probed symbol is longer than 64 bytes, it will generate a hashed event > > name with 64-byte length to avoid failure. > > Please CC Masami for probe related changes in the future. Thanks Namhyung, Let me find the patches. > > Thanks, > Namhyung > > > > > > > Leo Yan (3): > > perf: Dynamically allocate buffer for event string > > perf probe: Check group string length > > perf probe: Generate hash event for long symbol > > > > tools/perf/util/probe-event.c | 71 ++++++++++++++++++++++++++++++++--- > > 1 file changed, 65 insertions(+), 6 deletions(-) > > > > -- > > 2.34.1 > > -- Masami Hiramatsu (Google)