From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2F3BE1BD9ED; Thu, 31 Oct 2024 09:05:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730365536; cv=none; b=jRLFUHaDhawOOosw6jwRBzwt5fS8zFezPukS0atGK0S42PyfSRRdJQh11Nfiy/YiLnpuZ+l2Ho3dy6KrwOfC8BwEiw2iYK1HEn9yPixKjAEWTrkCmnDTxWJ8j14+jbkH1kKDs9bW0G4KNkjvoLoCkFsGmKuFJiNfzc90Q6GS5M0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730365536; c=relaxed/simple; bh=GG1JVJs4dR1AOjE1AJ7ilFPgtAWW0eecmwqTp/vt+xo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JL4tYAR5kRcDvdtnAsHyh0rE+tlwPiEGJmicXcf1WZbwYu19Wuo6qD54KAXfllD83qohOO84Y3TImntX5oYPtHLMqoCRyYw9Ghduf33ADU9ivkGJQ0JlE4J9BWHYTid3RblvUAGNLjMdQvMeNxVLEBjOA9nvesucvGgkw6/C5kk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QmlWshUd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QmlWshUd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E46ACC4CEC3; Thu, 31 Oct 2024 09:05:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730365535; bh=GG1JVJs4dR1AOjE1AJ7ilFPgtAWW0eecmwqTp/vt+xo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QmlWshUdBNcB1FWxXRPNndrpzxX3aAqhzeAeIGagnyn4fy5f45tGBkaDIMtVIOMSH f2449uvXl29R43CYnG1NWyJNJFs8AcYS+J3/4AoaP+t4DGqAhmFlaAi0DonSP1IJXs nqTFKGmBX62BU7Kq02whoNjJqhZNJXu4xTMAUf5TA9MsBWXeKgqU/7OfPHX4JQdM6Q cYeO/+jCF2CQ7VRPVWNfb4dd0leBLAU/Wm+kzEVcI2myW0Ik/rO07OwQb1Z9w7wpM9 cbflE1vTPSMudvnmxNiKBwpQsf9zOOlAijHfeIWAa1xqN0InkTRlZPm0qFA7PRteHE VKaKdM1Y44eGA== Date: Thu, 31 Oct 2024 11:05:30 +0200 From: Leon Romanovsky To: Christoph Hellwig , Jens Axboe Cc: Jason Gunthorpe , Robin Murphy , Joerg Roedel , Will Deacon , Sagi Grimberg , Keith Busch , Bjorn Helgaas , Logan Gunthorpe , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Marek Szyprowski , =?iso-8859-1?B?Suly9G1l?= Glisse , Andrew Morton , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v1 00/17] Provide a new two step DMA mapping API Message-ID: <20241031090530.GC7473@unreal> References: <3144b6e7-5c80-46d2-8ddc-a71af3c23072@kernel.dk> <20241031083450.GA30625@lst.de> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241031083450.GA30625@lst.de> On Thu, Oct 31, 2024 at 09:34:50AM +0100, Christoph Hellwig wrote: > On Wed, Oct 30, 2024 at 07:44:13PM -0600, Jens Axboe wrote: > > On Christoph's request, I tested this series last week and saw some > > pretty significant performance regressions on my box. I don't know what > > the status is in terms of that, just want to make sure something like > > this doesn't get merged until that is both fully understood and sorted > > out. This series is a subset of the series you tested and doesn't include the block layer changes which most likely were the cause of the performance regression. This is why I separated the block layer changes from the rest of the series and marked them as RFC. The current patch set is viable for HMM and VFIO. Can you please retest only this series and leave the block layer changes for later till Christoph finds the answer for the performance regression? Thanks > > Working on it, but I have way too many things going on at once. Note > that the weird thing about your setup was that we apparently dropped into > the slow path, which still puzzles me. But I should probably also look > into making that path a little less slow. > >