From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan Cameron Subject: Fostering linux community collaboration on hardware accelerators Date: Tue, 10 Oct 2017 12:28:05 +0100 Message-ID: <20171009112425.00003966@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit To: , "Liguozhu (Kenneth) " , Ilias Apalodimas , , , , Alex Williamson , Frederic Barrat , Andrew Donnellan , Mark Brown , , , Ard Biesheuvel , Jean-Philippe Brucker , Kirti Wankhede , "Eric Auger" , , , Return-path: Sender: kvm-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org Hi All, Please forward this email to anyone you think may be interested. On behalf of Huawei, I am looking into options to foster a wider community around the various ongoing projects related to Accelerator support within Linux. The particular area of interest to Huawei is that of harnessing accelerators from userspace, but in a collaborative way with the kernel still able to make efficient use of them, where appropriate. We are keen to foster a wider community than one just focused on our own current technology. This is a field with no clear answers, so the widest possible range of input is needed! The address list of this email is drawn from people we have had discussions with or who have been suggested in response to Kenneth Lee's wrapdrive presentation at Linaro Connect and earlier presentations on the more general issue. A few relevant lists added to hopefully catch anyone we missed. My apologies to anyone who got swept up in this and isn't interested! Here we are defining accelerators fairly broadly - suggestions for a better term are also welcome. The infrastructure may be appropriate for: * Traditional offload engines - cryptography, compression and similar * Upcoming AI accelerators * ODP type requirements for access to elements of networking * Systems utilizing SVM including CCIX and other cache coherent buses * Many things we haven't thought of yet... As I see it, there are several aspects to this: 1) Kernel drivers for accelerators themselves. * Traditional drivers such as crypto etc - These already have their own communities. The main focus of such work will always be through them. - What a more general community could add here would be an overview of the shared infrastructure of such devices. This is particularly true around VFIO based (or similar) userspace interfaces with a non trivial userspace component. * How to support new types of accelerator? 2) The need for lightweight access paths from userspace that 'play well' and share resources etc with standard in-kernel drivers. This is the area that Kenneth Lee and Huawei have been focusing on with their wrapdrive effort. We know there are other similar efforts going on in other companies. * This may involve interacting with existing kernel communities such as those around VFIO and mdev. * Resource management when we may have many consumers - not all hardware has appropriate features to deal with this. 3) Usecases for accelerators. e.g. * kTLS * Storage encryption * ODP - networking dataplane * AI toolkits Discussions we want to get started include: * A wider range of hardware than we are currently considering. What makes sense to target / what hardware do people have they would like to support? * Upstream paths - potential blockers and how to overcome them. The standard kernel drivers should be fairly straightforward, but once we start looking at systems with a heavier userspace component, things will get more controversial! * Fostering stronger userspace communities to allow these these accelerators to be easily harnessed. So as ever with a linux community focusing on a particular topic, the obvious solution is a mailing list. There are a number of options on how do this. 1) Ask one of the industry bodies to host? Who? 2) Put together a compelling argument for linux-accelerators@vger.kernel.org as probably the most generic location for such a list. More open questions are 1) Scope? * Would anyone ever use such an overarching list? * Are we better off with the usual adhoc list of 'interested parties' + lkml? * Do we actually need to define the full scope - are we better with a vague definition? 2) Is there an existing community we can use to discuss these issues? (beyond the obvious firehose of LKML). 3) Who else to approach for input on these general questions? In parallel to this there are elements such as git / patchwork etc but they can all be done as they are needed. Thanks -- Jonathan Cameron Huawei