Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934481AbaGPAGJ (ORCPT ); Tue, 15 Jul 2014 20:06:09 -0400 Received: from terminus.zytor.com ([198.137.202.10]:32818 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932982AbaGPAGF (ORCPT ); Tue, 15 Jul 2014 20:06:05 -0400 Message-ID: <53C5C1C9.6070100@zytor.com> Date: Tue, 15 Jul 2014 17:05:29 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 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 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> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/