From owner-svn-src-all@FreeBSD.ORG Sun Dec 29 02:44:51 2013 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B23F55FE; Sun, 29 Dec 2013 02:44:51 +0000 (UTC) Received: from mail.xcllnt.net (mail.xcllnt.net [50.0.150.214]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 6854F1F98; Sun, 29 Dec 2013 02:44:51 +0000 (UTC) Received: from [192.168.2.84] (50-0-150-213.dsl.static.sonic.net [50.0.150.213]) (authenticated bits=0) by mail.xcllnt.net (8.14.7/8.14.7) with ESMTP id rBT2inAM009816 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Sat, 28 Dec 2013 18:44:50 -0800 (PST) (envelope-from marcel@xcllnt.net) Content-Type: multipart/signed; boundary="Apple-Mail=_74A7F0B3-FBE7-45BE-9813-536FAE1F82CC"; protocol="application/pgp-signature"; micalg=pgp-sha1 Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Subject: Re: svn commit: r259908 - head/sys/vm From: Marcel Moolenaar In-Reply-To: <52BF6699.1040006@freebsd.org> Date: Sat, 28 Dec 2013 18:45:11 -0800 Message-Id: <14556BDB-35C3-49CE-896A-DEA8B1EB5B9C@xcllnt.net> References: <201312260546.rBQ5kAoJ009798@svn.freebsd.org> <52BF6699.1040006@freebsd.org> To: Nathan Whitehorn X-Mailer: Apple Mail (2.1827) Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, Marcel Moolenaar , src-committers@freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.17 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: Sun, 29 Dec 2013 02:44:51 -0000 --Apple-Mail=_74A7F0B3-FBE7-45BE-9813-536FAE1F82CC Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii On Dec 28, 2013, at 4:02 PM, Nathan Whitehorn wrote: > On 12/26/13 00:46, Marcel Moolenaar wrote: >> Author: marcel >> Date: Thu Dec 26 05:46:10 2013 >> New Revision: 259908 >> URL: http://svnweb.freebsd.org/changeset/base/259908 >> >> Log: >> For ia64, use pmap_remove_pages() and not pmap_remove(). The problem is >> that we don't have a good way (yet) to iterate over the mapped pages by >> virtual address and simply try each page within the range. Given that we >> call pmap_remove() over the entire 2^63 bytes of address space, it takes >> a while for pmap_remove to have tried all 2^50 pages. >> By using pmap_remove_pages() we use the PV list to find all mappings. >> >> Change derived from a patch by: alc >> > > Why make this ia64-specific? It seems like a potentially useful general > optimization and certainly shouldn't be harmful on other architectures. What alc@ said. Making it generic requires a bit more work and it's not clear to me whether it's a good change. Basically, ia64 fails to handle the pmap_remove() interface. So, for now I see it as a quick fix. What happens next is open. We're thinking of using the new trie code to track PTEs per PMAP. This helps to support pmap_remove() efficiently and may have other advantages. -- Marcel Moolenaar marcel@xcllnt.net --Apple-Mail=_74A7F0B3-FBE7-45BE-9813-536FAE1F82CC Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org iEYEARECAAYFAlK/jLcACgkQpgWlLWHuifZwCACeKGw0BUH3uRFlN1ovJyHIwQdX MK0AmwZsBLfjxyaAaxKxRU75Jrmf6LCc =qidu -----END PGP SIGNATURE----- --Apple-Mail=_74A7F0B3-FBE7-45BE-9813-536FAE1F82CC--