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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2AAA7C63697 for ; Tue, 17 Nov 2020 21:29:45 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7A58224181 for ; Tue, 17 Nov 2020 21:29:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="VC75sZ0s" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A58224181 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 0B1BD86FC6; Tue, 17 Nov 2020 21:29:44 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ajcB-o3Fwx0S; Tue, 17 Nov 2020 21:29:42 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 195F486FBF; Tue, 17 Nov 2020 21:29:42 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 09F4BC0800; Tue, 17 Nov 2020 21:29:42 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id B25F7C07FF for ; Tue, 17 Nov 2020 21:29:41 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 9953485085 for ; Tue, 17 Nov 2020 21:29:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jCDsnOq731Pe for ; Tue, 17 Nov 2020 21:29:39 +0000 (UTC) X-Greylist: delayed 00:08:04 by SQLgrey-1.7.6 Received: from mail-oi1-f193.google.com (mail-oi1-f193.google.com [209.85.167.193]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 7C90F85082 for ; Tue, 17 Nov 2020 21:29:39 +0000 (UTC) Received: by mail-oi1-f193.google.com with SMTP id t16so24175912oie.11 for ; Tue, 17 Nov 2020 13:29:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qaFR/vbXEE/Fp6N4YA11Mip+TFc+3mxIxAGB0BrXskE=; b=VC75sZ0sI622cqRm8NQfeG/nHdIrHJG5hf4nb18w5Ezfn7dMY95pE7f6ymO6jyVG5b RHrNPQPAkIvmJQcyxl/7knSpyGi+tr36KXPjdVxT8PNSHF++jwPSbnADEtdQfMS8xGvM xybni7VT4JkWf5GIe8nK7+qGTJhJlnTpen1Hc= 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; bh=qaFR/vbXEE/Fp6N4YA11Mip+TFc+3mxIxAGB0BrXskE=; b=Wgkrf+/+pYrKAJhFJafjrq6GKFNvLYpCdrSUu/3IFKXua5nkAueG9rKLctTkMB6WaW v6dUr+0a8PKT4xwWchtFDYufmQELLOMV+SW8hfm2RoioU119JYBofRw07O9DXlEJDCzU AuglGbEDlWFoM3bzL3DfQiJYDIZ83BR2QFiCh+1Aes2LC0MonwbE1HUx8sVY4d+i6HMn WDQfDesAOIaGOn/gzGKZntz8W1a2WMDIsP9lZVVUK65tE+ifjOXbNvpXWper7hB6jXFT QPYXee5ZJ/57VZjkX55SRsJwUW7UL/6mbgAkS1qX3s806ANWos149kLg7S7tv/SHiDox aNwQ== X-Gm-Message-State: AOAM530aNqw3u0p+6SWHOn8hqQx7IdjreoVfb4+jBDt8DdERzLLRIhMG 7XTNQ9fyg0B1/9JauzPmja120ppghjeJQ7JP X-Google-Smtp-Source: ABdhPJySVU2CmSPZ7EK7XwQu/p5gj3X3AGh7VJ9X0SPN7gjkBmBvQDVWfhCvCwt5pmsA+MvHvtqE7A== X-Received: by 2002:aca:c311:: with SMTP id t17mr769481oif.46.1605648094443; Tue, 17 Nov 2020 13:21:34 -0800 (PST) Received: from mail-oi1-f173.google.com (mail-oi1-f173.google.com. [209.85.167.173]) by smtp.gmail.com with ESMTPSA id q10sm6507112oih.56.2020.11.17.13.21.32 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Nov 2020 13:21:33 -0800 (PST) Received: by mail-oi1-f173.google.com with SMTP id d9so24208604oib.3 for ; Tue, 17 Nov 2020 13:21:32 -0800 (PST) X-Received: by 2002:aca:7506:: with SMTP id q6mr742413oic.128.1605648092412; Tue, 17 Nov 2020 13:21:32 -0800 (PST) MIME-Version: 1.0 References: <20200930160917.1234225-1-hch@lst.de> <20200930160917.1234225-9-hch@lst.de> <20201110092506.GA24469@lst.de> <20201110095747.GA26574@lst.de> In-Reply-To: <20201110095747.GA26574@lst.de> From: Ricardo Ribalda Date: Tue, 17 Nov 2020 22:21:21 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 8/8] WIP: add a dma_alloc_contiguous API To: Christoph Hellwig Cc: Linux Media Mailing List , Linux Doc Mailing List , Linux Kernel Mailing List , Kieran Bingham , "list@263.net:IOMMU DRIVERS , Joerg Roedel , " , Laurent Pinchart , Mauro Carvalho Chehab , Robin Murphy X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi Christoph I have been testing with real hardware on arm64 your patchset. And uvc performs 20 times better using Kieran's test https://github.com/ribalda/linux/tree/uvc-noncontiguous These are the result of running yavta --capture=1000 dma_alloc_noncontiguous frames: 999 packets: 999 empty: 0 (0 %) errors: 0 invalid: 0 pts: 0 early, 0 initial, 999 ok scr: 0 count ok, 0 diff ok sof: 2048 <= sof <= 0, freq 0.000 kHz bytes 78466000 : duration 33303 FPS: 29.99 URB: 418105/5000 uS/qty: 83.621 avg 98.783 std 17.396 min 1264.688 max (uS) header: 100040/5000 uS/qty: 20.008 avg 19.458 std 2.969 min 454.167 max (uS) latency: 347653/5000 uS/qty: 69.530 avg 98.937 std 9.114 min 1256.875 max (uS) decode: 70452/5000 uS/qty: 14.090 avg 11.547 std 6.146 min 271.510 max (uS) raw decode speed: 8.967 Gbits/s raw URB handling speed: 1.501 Gbits/s throughput: 18.848 Mbits/s URB decode CPU usage 0.211500 % usb_alloc_coherent frames: 999 packets: 999 empty: 0 (0 %) errors: 0 invalid: 0 pts: 0 early, 0 initial, 999 ok scr: 0 count ok, 0 diff ok sof: 2048 <= sof <= 0, freq 0.000 kHz bytes 70501712 : duration 33319 FPS: 29.98 URB: 1854128/5000 uS/qty: 370.825 avg 417.133 std 14.539 min 2875.760 max (uS) header: 98765/5000 uS/qty: 19.753 avg 30.714 std 1.042 min 573.463 max (uS) latency: 453316/5000 uS/qty: 90.663 avg 114.987 std 4.065 min 860.795 max (uS) decode: 1400811/5000 uS/qty: 280.162 avg 330.786 std 6.305 min 2758.202 max (uS) raw decode speed: 402.866 Mbits/s raw URB handling speed: 304.214 Mbits/s throughput: 16.927 Mbits/s URB decode CPU usage 4.204200 % Best regards On Tue, Nov 10, 2020 at 10:57 AM Christoph Hellwig wrote: > > On Tue, Nov 10, 2020 at 06:50:32PM +0900, Tomasz Figa wrote: > > In what terms it doesn't actually work? Last time I checked some > > platforms actually defined CONFIG_DMA_NONCOHERENT, so those would > > instead use the kmalloc() + dma_map() path. I don't have any > > background on why that was added and whether it needs to be preserved, > > though. Kieran, Laurent, do you have any insight? > > CONFIG_DMA_NONCOHERENT is set on sh and mips for platforms that may > support non-coherent DMA at compile time (but at least for mips that > doesn't actually means this gets used). Using that ifdef to decide > on using usb_alloc_coherent vs letting the usb layer map the data > seems at best odd, and if we are unlucky papering over a bug somewhere. -- Ricardo Ribalda _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu