Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S271056AbUJVKhO (ORCPT ); Fri, 22 Oct 2004 06:37:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S271058AbUJVKhO (ORCPT ); Fri, 22 Oct 2004 06:37:14 -0400 Received: from holomorphy.com ([207.189.100.168]:44993 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S271056AbUJVKhN (ORCPT ); Fri, 22 Oct 2004 06:37:13 -0400 Date: Fri, 22 Oct 2004 03:37:08 -0700 From: William Lee Irwin III To: Christoph Lameter Cc: "Chen, Kenneth W" , raybry@sgi.com, linux-kernel@vger.kernel.org Subject: Re: Hugepages demand paging V1 [2/4]: set_huge_pte() arch updates Message-ID: <20041022103708.GK17038@holomorphy.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: The Domain of Holomorphy User-Agent: Mutt/1.5.6+20040722i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1144 Lines: 24 On Thu, Oct 21, 2004 at 09:57:23PM -0700, Christoph Lameter wrote: > Changelog > * Update set_huge_pte throughout all arches > * set_huge_pte has an additional address argument > * set_huge_pte must also do what update_mmu_cache typically does > for PAGESIZE ptes. > Signed-off-by: Christoph Lameter What's described above is not what the patch implements. The patch is calling update_mmu_cache() in a loop on all the virtual base pages of a virtual hugepage, which won't help at all, as it doesn't understand how to find the hugepages regardless of virtual address. AFAICT code to actually do the equivalent of update_mmu_cache() on hugepages most likely involves privileged instructions and perhaps digging around some cpu-specific data structures (e.g. the natively architected pagetables bearing no resemblance to Linux') for almost every non-x86 architecture. -- wli - 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/