From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9D14C433EF for ; Fri, 19 Nov 2021 06:12:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92498610A0 for ; Fri, 19 Nov 2021 06:12:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233614AbhKSGPX (ORCPT ); Fri, 19 Nov 2021 01:15:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59596 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232884AbhKSGPV (ORCPT ); Fri, 19 Nov 2021 01:15:21 -0500 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D91BCC061757; Thu, 18 Nov 2021 22:12:20 -0800 (PST) Received: by mail-pl1-x642.google.com with SMTP id q17so7315044plr.11; Thu, 18 Nov 2021 22:12:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=0vlFTFNGU4TzImjGgcP9WVs/xDWGV6QhBtB/igQrgA4=; b=X7/coZFc3LVK0ZZb/OnK+LCoxog0ZJTF699urYd6fPETAfpodMkL6g/3ZgSqHKs5z2 afc3s3MuBToYBDB7mArLWqa17pi+OlpDK3Q6LrdxBkzYeEsWnDDQ7lsas/k89W6r/ggo bCa4a3tcJ1uwa/P2cFbfqnJjDMgZQRyL95aBf5TbRZV3C+8HE62xARRMrpndcWqfpIH7 Q6UItcpEh67LBz6JjF/lPrO4E6w7NwaIHW8KYRl+xi7Yn61gEhdtP4rSoB4WZ3uYykUJ 6s4TKjXYLJSv6OVOZVtq2gYHCZxaGdI71xUN8IHOwvWwJYtWS2sLiVC8hb0sOA7QqzcN 5uzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=0vlFTFNGU4TzImjGgcP9WVs/xDWGV6QhBtB/igQrgA4=; b=iNR3/kEo7VnU/qfIKh5XN178Dy4uk7bb7mIrzV/s/wlgrtE6W+FtXVgCdTVvsH8Jrg m102mAi/gVM7jCN3PtJX5BVRXDqX2yWwNLZ/Y+MpErqh4fpxIju8pwlNbU4GnGEXedM0 0cBQMHq9A2JNbFRKt4PvhdlBffeUMju3f0bL1IIuMjpZEaMJO5NEFiGbdDGDU+0bvz/9 puS/Od08+Cf/Otjth6baMFBGCAMrk8V5qrexXpZ6SRMDpb82d1qq7Vjr0uIKqwEIrLs6 p4k5Kj3YUy7zA1385VCZv4MHblQWmi3p5R3Vj54RNwPPobv0acIYkKL1R9aWdR59bjM2 GAqw== X-Gm-Message-State: AOAM532cs7IH+qOp2FkvUf9fYndVgMoWcAy+I3F2+EVGEN+cIxhS2wXF qSf0zD2SnNDt6QZyfsYXcFM= X-Google-Smtp-Source: ABdhPJxI4BfYYOZRQP+jdrzJ/tejEWy9hQ0mjL5s/RWDjxlO0QpAnXIUcYBXTDeJpxrk5shmSgjJww== X-Received: by 2002:a17:90b:1c06:: with SMTP id oc6mr1699541pjb.126.1637302340312; Thu, 18 Nov 2021 22:12:20 -0800 (PST) Received: from localhost ([2405:201:6014:d064:502e:73f4:8af1:9522]) by smtp.gmail.com with ESMTPSA id oa17sm1192722pjb.37.2021.11.18.22.12.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Nov 2021 22:12:19 -0800 (PST) Date: Fri, 19 Nov 2021 11:42:15 +0530 From: Kumar Kartikeya Dwivedi To: Alexei Starovoitov Cc: bpf , Jens Axboe , Pavel Begunkov , io-uring@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Pavel Emelyanov , Alexander Mihalicyn , Andrei Vagin , criu@openvz.org, Linux-Fsdevel Subject: Re: [PATCH bpf-next v1 1/8] io_uring: Implement eBPF iterator for registered buffers Message-ID: <20211119061215.3kcz6r6em7g4p3vr@apollo.localdomain> References: <20211116054237.100814-1-memxor@gmail.com> <20211116054237.100814-2-memxor@gmail.com> <20211118220226.ritjbjeh5s4yw7hl@ast-mbp.dhcp.thefacebook.com> <20211119041523.cf427s3hzj75f7jr@apollo.localdomain> <20211119045659.vriegs5nxgszo3p3@ast-mbp.dhcp.thefacebook.com> <20211119051657.5334zvkcqga754z3@apollo.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Fri, Nov 19, 2021 at 10:54:21AM IST, Alexei Starovoitov wrote: > On Thu, Nov 18, 2021 at 9:17 PM Kumar Kartikeya Dwivedi > wrote: > > > > On Fri, Nov 19, 2021 at 10:26:59AM IST, Alexei Starovoitov wrote: > > > On Fri, Nov 19, 2021 at 09:45:23AM +0530, Kumar Kartikeya Dwivedi wrote: > > > > > > > > Also, this work is part of GSoC. There is already code that is waiting for this > > > > to fill in the missing pieces [0]. If you want me to add a sample/selftest that > > > > demonstrates/tests how this can be used to reconstruct a task's io_uring, I can > > > > certainly do that. We've already spent a few months contemplating on a few > > > > approaches and this turned out to be the best/most powerful. At one point I had > > > > to scrap some my earlier patches completely because they couldn't work with > > > > descriptorless io_uring. Iterator seem like the best solution so far that can > > > > adapt gracefully to feature additions in something seeing as heavy development > > > > as io_uring. > > > > > > > > [0]: https://github.com/checkpoint-restore/criu/commit/cfa3f405d522334076fc4d687bd077bee3186ccf#diff-d2cfa5a05213c854d539de003a23a286311ae81431026d3d50b0068c0cb5a852 > > > > [1]: https://github.com/checkpoint-restore/criu/pull/1597 > > > > > > Is that the main PR? 1095 changed files? Is it stale or something? > > > Is there a way to view the actual logic that exercises these bpf iterators? > > > > No, there is no code exercising BPF iterator in that PR yet (since it wouldn't > > build/run in CI). There's some code I have locally that uses these to collect > > the necessary information, I can post that, either as a sample or selftest in > > the next version, or separately on GH for you to take a look. > > > > I still rebased it so that you can see the rest of the actual code. > > I would like to see a working end to end solution. > Understood, I'll address this in v2. > Also I'd like to hear what Jens and Pavel have to say about > applicability of CRIU to io_uring in general. -- Kartikeya