From owner-freebsd-amd64@FreeBSD.ORG Wed Nov 5 17:52:30 2014 Return-Path: Delivered-To: freebsd-amd64@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 0A13C81A for ; Wed, 5 Nov 2014 17:52:30 +0000 (UTC) Received: from mail-ie0-f173.google.com (mail-ie0-f173.google.com [209.85.223.173]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id C9DB3F32 for ; Wed, 5 Nov 2014 17:52:29 +0000 (UTC) Received: by mail-ie0-f173.google.com with SMTP id tr6so1217358ieb.18 for ; Wed, 05 Nov 2014 09:52:22 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=QzhKclLinZcc1W6IGtN+RECBqE4pAOARa8QMVj70VOo=; b=C9sxMn4NOyxjJKQB+gOBlS28BAPeJMTJ5w3R4dVel0Tt2Z2W1fQrJiEEtfiKOGbxnS WHn9lMws6rpy0pQk1r0dICzrMcXAfT7RC0HvRElaDvePDsCS5st+w5ydx58YhUkamhr8 j1aODCvOxZHVmL7+fXBOnYyMSp+IVqjgVuJyvrJ4NJYRFx0EL6fmCm1Q1ozPladMgEB1 TcVtnKkp4ByNFNRyLlxEQfgk3NoOJsyUBxWIkBLDTBRZMcj0ab4pZ2KXHwGY/wc7pOvj KHNOP4Fy0a33Wgz+w+rInWAvEISbs0cSs75FIM0o/I8zRkvgZE5UGSXo82dDZVugpu01 W4Ag== X-Gm-Message-State: ALoCoQl2kbnmfN87Aj5AcAwk0RypuJa8BZian2TKH3JivCrKvePmIKkYKhELCd2/N9xWptD7QhTT MIME-Version: 1.0 X-Received: by 10.43.87.79 with SMTP id av15mr6179809icc.44.1415209942052; Wed, 05 Nov 2014 09:52:22 -0800 (PST) Received: by 10.107.52.144 with HTTP; Wed, 5 Nov 2014 09:52:21 -0800 (PST) In-Reply-To: <20141104084628.GN53947@kib.kiev.ua> References: <201410301353.05185.jhb@freebsd.org> <3381641.WgZAz21Lfu@pippin.baldwin.cx> <20141104084628.GN53947@kib.kiev.ua> Date: Wed, 5 Nov 2014 23:22:21 +0530 Message-ID: Subject: Re: memory type e820 From: Sourish Mazumder To: Konstantin Belousov Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 Cc: freebsd-amd64@freebsd.org X-BeenThere: freebsd-amd64@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Porting FreeBSD to the AMD64 platform List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Nov 2014 17:52:30 -0000 Should there be any difference in performance while writing to a memory as cached versus uncached mapping? On Tue, Nov 4, 2014 at 2:16 PM, Konstantin Belousov wrote: > On Mon, Nov 03, 2014 at 01:52:44PM -0500, John Baldwin wrote: > > On Saturday 01 November 2014 18:55:53 Sourish Mazumder wrote: > > > Hi John, > > > > > > I tried the pmap_mapdev() as suggested by you. Works perfectly. Thanks > for > > > the information. > > > > Sure. > > > > > What is required, If I want to add this nvram memory to VM pages? > > > > Hmm. If this is device memory you generally don't want that. I'm not > > actually sure how to do this at runtime. If you don't mind having a > local > > hack you can add a change in the MD startup code (e.g. in hammer_time() > > in sys/amd64/amd64/machdep.c) to adjust the ranges added to > > phys_avail[] and dump_avail[]. > > The facility exists to do this. It is OBJT_MGTDEVICE pager and > vm_phys_fictitious_reg_range(). This is used by i915 and TTM for > aperture, and seems XEN dom0 code uses it for mapping pages from > other domains into dom0. > -- Sourish Mazumder 9986309755