From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 17B17A00C4; Thu, 28 Jul 2022 09:25:43 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 4971B427ED; Thu, 28 Jul 2022 09:25:40 +0200 (CEST) Received: from mail-lj1-f176.google.com (mail-lj1-f176.google.com [209.85.208.176]) by mails.dpdk.org (Postfix) with ESMTP id 53FBA40E25 for ; Thu, 28 Jul 2022 09:25:39 +0200 (CEST) Received: by mail-lj1-f176.google.com with SMTP id w16so588274ljh.3 for ; Thu, 28 Jul 2022 00:25:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=MOU661I169sdGpEKmpyhpp1pyq7UnJ1c5bW0PZAc4Eg=; b=I83U7xo4ykV3ULqLXV/x7vyzBNScY/3wYvapepvXkxwwsDE6KRrAQUI8pkS2KP8XOJ h08zj0V9p8kb8f9Ca4p64K4Qb9y0LMaVF9YH/wCt8r9pYrnrk25x3d1jROM5lhgqYF51 IRjYMi42QKoE1vAJxpPyb5SUu6xVLlLSvq7aW5LpWgT12K3zaUtWvUGEmO0/0lGfTK75 mYwkCnsnsQz4TxKm0Xx6XU8MJkyDNGU3NrdUY7wZetWwSf3JMP6dqRiKBlVaoVUdWaeN xwmLMc7PNS3HC2+NZs+fdvzQWuATBdC/VxL9EdZjrIMgN4DeJ8EaJnEhsaYSAjAVcbRr zqFQ== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=MOU661I169sdGpEKmpyhpp1pyq7UnJ1c5bW0PZAc4Eg=; b=brgYSe6QVnkngwyyF+vYmwnbIMa11/xOSpujtDZrNjPYNyOcUK7sXlikUYla4Bl8vx U10wkD/UkbZCXPdpi0g6nbmNZvfFSe8yzUZD4pC7FBGzsc+KJny3t9ph+uI974ZM2tsZ QWY+bJIbU6kBW7uvazmEEIebGiXTyahOA3c6MGROMiyjUchwHx44jRn3CzASwCa5MEGU uU5ZK8YdDncUEVLcN6ywGveVgYcMN34Z5+DfeJCQSGjDBPX7RfiXkp6ZNRwxqPUX/Qte AF7G6nnyyC5caZ62XAE76TGNcohan0TyV/sAjM4QUheKsGm8vQrIaClm9rBvJUEiF/0x EG6w== X-Gm-Message-State: AJIora/gPV2pN96D2fdoVM8QY68SHaDe54uXW6H97o/1ynM8jR58lZq4 4yv3lOeiSKi5MxUXoR1oZ0Q= X-Google-Smtp-Source: AGRyM1uSNRIPVo3SoxwUz12s7yUvvXOc6LaND6MD/D7zge7n5Aq7UFZ/EvX7ML2GqLFD9KgMrAWWlw== X-Received: by 2002:a2e:b52a:0:b0:25d:f323:791c with SMTP id z10-20020a2eb52a000000b0025df323791cmr8360812ljm.417.1658993138611; Thu, 28 Jul 2022 00:25:38 -0700 (PDT) Received: from sovereign (broadband-37-110-65-23.ip.moscow.rt.ru. [37.110.65.23]) by smtp.gmail.com with ESMTPSA id o15-20020ac24e8f000000b0048a407f41bbsm55425lfr.238.2022.07.28.00.25.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Jul 2022 00:25:38 -0700 (PDT) Date: Thu, 28 Jul 2022 10:25:37 +0300 From: Dmitry Kozlyuk To: Don Wallwork Cc: "dev@dpdk.org" Subject: Re: [RFC] EAL: legacy memory fixed address translations Message-ID: <20220728102537.48ff6e5f@sovereign> In-Reply-To: References: <256b5409-ddaf-d7cc-00c1-273ca76dbf71@xsightlabs.com> <6aaa04d8-2ac5-ced6-ec25-d42bc52a3e2f@xsightlabs.com> <20220726225910.26159820@sovereign> <20220727233644.21f0b2a3@sovereign> X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org 2022-07-27 17:43 (UTC-0400), Don Wallwork: > On 7/27/2022 4:36 PM, Dmitry Kozlyuk wrote: > > I now understand more about_why_ you want this feature > > but became less confident_what_ do you're proposing specifically. > > Let me try to give a trivial example of how it would work > to make sure we're on the same page and then we can get > back to details.. Thanks you, Don. Now it's perfectly clear what EAL should do and we can discuss API. [...] > So in this example, we have a fixed offset of 9G to translate > between VA to PA or vice versa.This works whether the huge > pages happen to be allocated statically (legacy mode) or > dynamically. True! One special case is external memory (rte_extmem_*) which has user-controlled VA and IOVA. If all non-external memory is mapped within one VA region, it is possible to detect that an address is in external memory, although it's an extra check.