From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x230.google.com (mail-qt0-x230.google.com [IPv6:2607:f8b0:400d:c0d::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 87D2E3B2A4 for ; Wed, 1 Aug 2018 15:20:23 -0400 (EDT) Received: by mail-qt0-x230.google.com with SMTP id b15-v6so21174114qtp.11 for ; Wed, 01 Aug 2018 12:20:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=0wlMdZ+diq73yl8f9DPTtUV4jIo9TMf4pD1ic0XXxng=; b=reYhFn2+ly/IicLJsLemQde4ULTQwybron+4jq8bzwNN9lCnRTC1uE+1d0JaMKxoFk fQjQzy65Ocrc33oH+DRBfIZRmJHzC5TgWfRKjMbAbJz18Zqh4L7Hl6mtuMBd/aLQw8ng 5YPqDxHN3QZPYCC4vKoedy+sedgoerlJXyYJyyELvgDLroR2HgnH53KzlNH62v22qpzR CF6QCj3G0/Asn6yB7MjzXgeRk7Cz3+kpTSZaD2UTvLbP8pYi6jQKRaZiF47zJGlpkfd2 xZTHvsbUhK6QnqbD7TCBcFzOy8intVahc27qLkc90UNbS8nchBlrnSfcC+ILKObZQSLL LQTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=0wlMdZ+diq73yl8f9DPTtUV4jIo9TMf4pD1ic0XXxng=; b=AEFyjoNWwG8P3wwK3x915CbY59wYY/sc9B5RP9XyFUiKmaafkSb5IxpQzhQw+7IHf0 WZWLVYSKoK1ecyzVYM/D/u2O7v3VQdebLxGeJ/Lsz8K2YQdXkbt/jPSmvkV26KOSmFlJ T8RcghNzqn46xGKnMMoxLznpNFm4oxV4nghXzqyCr9vAKGlc1LkOpa2QKhHzieZ2ano7 svMc7eYKcTXreKrNNexOd8K8r2g7PHY2hHHhz5dgOjA+E9EwJ7HYHGYmL1rXaiJjD4Kv awnlncit7FDAZc2ZXJt5f+anvFrRAFg3b6T5d9qz5LH5h0pax2K4ALo9jgztuKU2z7iq JyQA== X-Gm-Message-State: AOUpUlGUROhUc9JKt6taKSOK+m4SI+U9XTRXyX+Rff0snoeUfpQZCEF6 ovsU9EnffQI5UhTESiyQX8B0QevRmzHljmosocM= X-Google-Smtp-Source: AAOMgpfNQL/mYJ+w/RhaBEmI1ANR55nHpqv015wMvBQgLkLy7jX8BDIe4Fzo+tfbmqSLI5sD+bsCHQAF3LyyOtSS3A8= X-Received: by 2002:a0c:93b3:: with SMTP id f48-v6mr24529405qvf.151.1533151223120; Wed, 01 Aug 2018 12:20:23 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Dave Taht Date: Wed, 1 Aug 2018 12:20:46 -0700 Message-ID: To: Jonathan Morton Cc: Cake List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Cake] codel in ebpf? X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Aug 2018 19:20:23 -0000 On Wed, Aug 1, 2018 at 10:25 AM Dave Taht wrote: > > I wonder if ebpf has opcode space for an invsqrt? bpf_ktime_get_ns() exists... one thing that I don't know if bpf can do is read/write the skb->tstamp field. The plan would be to rigorously write it (if not supplied by hw) on all ingress ports and check it on all egress ports. That said, every time I've tried to do something in ebpf I hit a limitation I'd not thunk of yet. For example, where can you attach the egress filter? My thought would be to use a bfifo > bpf -> bql, but from what little I understand, it's bpf -> bfifo -> bql --=20 Dave T=C3=A4ht CEO, TekLibre, LLC http://www.teklibre.com Tel: 1-669-226-2619