From owner-svn-src-all@FreeBSD.ORG Thu Sep 9 16:20:04 2010 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 89AE01065697; Thu, 9 Sep 2010 16:20:04 +0000 (UTC) (envelope-from alc@rice.edu) Received: from mh1.mail.rice.edu (mh1.mail.rice.edu [128.42.201.20]) by mx1.freebsd.org (Postfix) with ESMTP id 597EA8FC1D; Thu, 9 Sep 2010 16:20:03 +0000 (UTC) Received: from mh1.mail.rice.edu (localhost.localdomain [127.0.0.1]) by mh1.mail.rice.edu (Postfix) with ESMTP id 42D3228F70D; Thu, 9 Sep 2010 11:01:40 -0500 (CDT) X-Virus-Scanned: by amavis-2.6.4 at mh1.mail.rice.edu, auth channel Received: from mh1.mail.rice.edu ([127.0.0.1]) by mh1.mail.rice.edu (mh1.mail.rice.edu [127.0.0.1]) (amavis, port 10026) with ESMTP id OdvSxPDBouxG; Thu, 9 Sep 2010 11:01:40 -0500 (CDT) Received: from adsl-216-63-78-18.dsl.hstntx.swbell.net (adsl-216-63-78-18.dsl.hstntx.swbell.net [216.63.78.18]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (No client certificate requested) (Authenticated sender: alc) by mh1.mail.rice.edu (Postfix) with ESMTPSA id AFD7128F6BA; Thu, 9 Sep 2010 11:01:39 -0500 (CDT) Message-ID: <4C8904E3.9000907@rice.edu> Date: Thu, 09 Sep 2010 11:01:39 -0500 From: Alan Cox User-Agent: Thunderbird 2.0.0.24 (X11/20100725) MIME-Version: 1.0 To: Nathan Whitehorn References: <201009091332.o89DWw9H087769@svn.freebsd.org> In-Reply-To: <201009091332.o89DWw9H087769@svn.freebsd.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r212360 - head/sys/vm X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Sep 2010 16:20:04 -0000 Nathan Whitehorn wrote: > Author: nwhitehorn > Date: Thu Sep 9 13:32:58 2010 > New Revision: 212360 > URL: http://svn.freebsd.org/changeset/base/212360 > > Log: > On architectures with non-tree-based page tables like PowerPC, every page > in a range must be checked when calling pmap_remove(). Calling > pmap_remove() from vm_pageout_map_deactivate_pages() with the entire range > of the map could result in attempting to demap an extraordinary number > of pages (> 10^15), so iterate through each map entry and unmap each of > them individually. > > This is a machine-dependent issue, and so I will argue that it is the pmap's and not the machine-independent layer's responsibility to deal with this. Our sparc64 port faces the same problem with the TSB, and it deals with it internally. Moreover, the solution isn't that complicated. Is there any reason why the sparc64 solution can't be applied to powerpc? Regards, Alan