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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 32993C2BB40 for ; Mon, 14 Dec 2020 13:37:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E5BB1229C5 for ; Mon, 14 Dec 2020 13:37:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439993AbgLNNg6 (ORCPT ); Mon, 14 Dec 2020 08:36:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2439600AbgLNNgq (ORCPT ); Mon, 14 Dec 2020 08:36:46 -0500 Received: from mail-qk1-x744.google.com (mail-qk1-x744.google.com [IPv6:2607:f8b0:4864:20::744]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 625CCC0613D3 for ; Mon, 14 Dec 2020 05:36:06 -0800 (PST) Received: by mail-qk1-x744.google.com with SMTP id b64so11464315qkc.12 for ; Mon, 14 Dec 2020 05:36:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=aSX7SZ34+utf+RIxSxOaDvrohcjpjOIx1rXwhtSGUWk=; b=Q2T0WIutJ+KnkQ+kPpVS+ZXIFPM3+uqjlwRi8rGHuCOgdnFgixHZ19jaapgZQZc4dv mM5s7muH4dPGs7c+Mc561ekdxd1Lcl4wPLt61CbpAcNC+ysA1jsmE5jOHS3oFjn2yHQQ 6qrOfyeWdRRgxddLFOXs9tUa4ktfbX9cceFJWY5Am+H4E039f51JACknkU694TI1ctST xWzDMsQ/nkTd3OAsHN0sWnMXSdKwkRv0dIPmu3YiyP6cTqRbNogWF/SmmM7Nb1vPQpG5 jquwiq7zL6pY1whY6t/ZEpaDoM9GTK7YTs6eiRgLqiPNLERLMeUDP1CZDOA0Nu5x95ZH lrlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=aSX7SZ34+utf+RIxSxOaDvrohcjpjOIx1rXwhtSGUWk=; b=R6UULCeMQ8jPmYaHrY2YWbrkFs2m/8qYgtejhu0GnrCzzBqxW8OYh4fSBK9ySdmNGT dc0OSdpgGJZkLbzN5nuHi1aDYO2BsuprKimVoR9A3EAyeNh3TVVRG9RJrL8HZ7HlFBSx q0XqxEN+ZrbJnTF56SOIbWDabftsRXech9/8bj/tmw4t8HZmuYaFNtkkx+mI4ec/5Py+ NmrJRxOpT1Bv8t3bQYHuUc/Fi/AmA6kHzHielESY0wUjkZcdvLa/3NDcV+ubshwMm9ka pd30L89otSM9r0pJM63n9Y0pBWKBCxcONAOB7BLTJFc6xJAg9knNEYYefRqsF3kF6TAK /Zzg== X-Gm-Message-State: AOAM530SrPCegfwSvNLhrYQTc0Eal3IX4fcPsNwyY8Cg9QZRbPDGuooy U9IgB1Xgqr7v7uGHchseR3UnNmO1G2CTpw== X-Google-Smtp-Source: ABdhPJwX7KgX9z0LpyhrKrmdAXAQlfWjO4BubE1fX04pxg+mf4spVzTLz9Tp6Y4EKzZ14AjqLFu/vg== X-Received: by 2002:a05:620a:95d:: with SMTP id w29mr31337314qkw.147.1607952965645; Mon, 14 Dec 2020 05:36:05 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-142-162-115-133.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.115.133]) by smtp.gmail.com with ESMTPSA id i17sm1366425qtg.77.2020.12.14.05.36.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Dec 2020 05:36:04 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1koo1D-00AHmi-4n; Mon, 14 Dec 2020 09:36:03 -0400 Date: Mon, 14 Dec 2020 09:36:03 -0400 From: Jason Gunthorpe To: David Hildenbrand Cc: Pavel Tatashin , LKML , linux-mm , Andrew Morton , Vlastimil Babka , Michal Hocko , Oscar Salvador , Dan Williams , Sasha Levin , Tyler Hicks , Joonsoo Kim , mike.kravetz@oracle.com, Steven Rostedt , Ingo Molnar , Peter Zijlstra , Mel Gorman , Matthew Wilcox , David Rientjes , John Hubbard , Linux Doc Mailing List Subject: Re: [PATCH v3 5/6] mm/gup: migrate pinned pages out of movable zone Message-ID: <20201214133603.GF5487@ziepe.ca> References: <20201211235005.GE5487@ziepe.ca> <2D10D596-3159-483C-81B4-CD187806ED46@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <2D10D596-3159-483C-81B4-CD187806ED46@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 12, 2020 at 08:29:11AM +0100, David Hildenbrand wrote: > > Racing with another GUP in another thread is also not reasonable, so > > failing to isolate can't be a failure > > Having VMs with multiple vfio containers is certainly realistic, and > optimizing in user space to do vfio mappings concurrently doesn‘t > sound too crazy to me. But I haven‘t checked if vfio common code > already handles such concurrency. There is a lot more out there than vfio.. RDMA already does concurrent pin_user_pages in real apps Jason