From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f52.google.com (mail-pa0-f52.google.com [209.85.220.52]) by kanga.kvack.org (Postfix) with ESMTP id 7F0426B0036 for ; Tue, 15 Jul 2014 20:05:59 -0400 (EDT) Received: by mail-pa0-f52.google.com with SMTP id bj1so197153pad.11 for ; Tue, 15 Jul 2014 17:05:59 -0700 (PDT) Received: from mail.zytor.com (terminus.zytor.com. [2001:1868:205::10]) by mx.google.com with ESMTPS id kg4si12950051pad.239.2014.07.15.17.05.58 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 15 Jul 2014 17:05:58 -0700 (PDT) Message-ID: <53C5C1C9.6070100@zytor.com> Date: Tue, 15 Jul 2014 17:05:29 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: [RFC PATCH 3/11] x86, mm, pat: Change reserve_memtype() to handle WT type References: <1405452884-25688-1-git-send-email-toshi.kani@hp.com> <1405452884-25688-4-git-send-email-toshi.kani@hp.com> <1405465801.28702.34.camel@misato.fc.hp.com> <1405468387.28702.53.camel@misato.fc.hp.com> In-Reply-To: <1405468387.28702.53.camel@misato.fc.hp.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Toshi Kani , Andy Lutomirski Cc: Thomas Gleixner , Ingo Molnar , Andrew Morton , Arnd Bergmann , Konrad Rzeszutek Wilk , plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Stefan Bader , Dave Airlie , Borislav Petkov On 07/15/2014 04:53 PM, Toshi Kani wrote: > > Right. > > I think using struct page table for the RAM ranges is a good way for > saving memory, but I wonder how often the RAM ranges are mapped other > than WB... If not often, reserve_memtype() could simply call > rbt_memtype_check_insert() for all ranges, including RAM. > > In this patch, I left using reserve_ram_pages_type() since I do not see > much reason to use WT for RAM, either. > They get flipped to WC or WT or even UC for some I/O devices, but ultimately the number of ranges is pretty small. -hpa -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org