From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lamorak.hansenpartnership.com (lamorak.hansenpartnership.com [198.37.111.173]) (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 44D8C2AE8E for ; Tue, 15 Jul 2025 14:38:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.37.111.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752590319; cv=none; b=X2hHf/NNk76XJ4FncQl6uglOSTJHSQEyolaB5X4kKAwa4KjpXFteMzpQjqriUwRT3HNeGdRFijTZQ0ARKFiSZ6eXGwYxfhwB+7Zs3AsLwzfQfAQPdCbFObWYyZI1iOzekZHyqlAhHsWd2yT5lT46LxxMx7l1OrjznaPyypqJLKE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752590319; c=relaxed/simple; bh=h3lMg00OPJxVzNkUq/zHFCm7QqJC6EafHIwYYZqmo3I=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; 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 8mT2Eh9SkH+YVOmaKsajgZgrBxA7fWmGoxXswEVxJIFj3vW7yNc0C5HaUdYa5iGOMs4kg2ht4s7yy7NRQuh7BifWjo6BQ6k4S1H+6axZucxhSV1L6zN9d+lr3Xo/vy1unzA== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2025-07-15 at 09:16 -0400, Steven Rostedt wrote: > On Tue, 15 Jul 2025 08:50:08 -0400 > James Bottomley wrote: > > What's wrong with doing this the other way around?=C2=A0 i.e. making > > ftrace and perf modules?=C2=A0 That way you could legitimately export > > the symbol you're asking about and there would be way less out-of- > > tree disadvantage to LTTng?=C2=A0 I know a lot of cloud people who woul= d > > be really happy if the tracing infrastructure were modular because > > it would save us from having to boot different kernels to do in > > depth problem analysis for otherwise locked down environments, so > > they might be willing to invest in upstream development to help you > > achieve this. >=20 > Well, if you can get those cloud people to invest in that work > without causing any regressions, go for it. I think you know as well as I no investment happens without some indication of upstream being in favour, particularly for large changes. So they're not going to invest in doing this on spec because it would be unmaintainable out of tree and would be way more hassle than simply having customers reboot as they do today. > But I doubt it would be acceptable to make the ftrace tracing > infrastructure into a module for the sole purpose of allowing LTTng > to have EXPORT_SYMBOL_GPL(). I don't believe I said that: purpose is not monolithic in open source because people do things for wildly different reasons which a clever leader can stitch together into something more synergistically useful. The cloud vendors would be invested solely for the purpose of being able to load tracing infrastructure on demand (with the permission of the tenant) into a running kernel. They wouldn't care at all about the symbol export problems of LTTng. However, working with the cloud vendors on what they want (and could be persuaded to invest in) would give you what you wanted: an in-tree consumer for these symbols. Regards, James