From owner-cvs-src@FreeBSD.ORG Mon Jan 14 21:25:07 2008 Return-Path: Delivered-To: cvs-src@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3146916A417; Mon, 14 Jan 2008 21:25:07 +0000 (UTC) (envelope-from alc@FreeBSD.org) Received: from repoman.freebsd.org (repoman.freebsd.org [IPv6:2001:4f8:fff6::29]) by mx1.freebsd.org (Postfix) with ESMTP id 016EB13C4D3; Mon, 14 Jan 2008 21:25:07 +0000 (UTC) (envelope-from alc@FreeBSD.org) Received: from repoman.freebsd.org (localhost [127.0.0.1]) by repoman.freebsd.org (8.14.1/8.14.1) with ESMTP id m0ELP6Bj050970; Mon, 14 Jan 2008 21:25:06 GMT (envelope-from alc@repoman.freebsd.org) Received: (from alc@localhost) by repoman.freebsd.org (8.14.1/8.14.1/Submit) id m0ELP6hX050969; Mon, 14 Jan 2008 21:25:06 GMT (envelope-from alc) Message-Id: <200801142125.m0ELP6hX050969@repoman.freebsd.org> From: Alan Cox Date: Mon, 14 Jan 2008 21:25:06 +0000 (UTC) To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org X-FreeBSD-CVS-Branch: HEAD Cc: Subject: cvs commit: src/sys/amd64/amd64 pmap.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 Jan 2008 21:25:07 -0000 alc 2008-01-14 21:25:06 UTC FreeBSD src repository Modified files: sys/amd64/amd64 pmap.c Log: Make pmap_is_prefaultable() more TLB friendly. Specifically, make it use the kernel's direct map instead of the pmap's recursive mapping to access the lowest level in the page table. The direct map is preferable for two reasons: (1) The TLB is more likely to hold the required direct mapping because pmap_enter() has already used the direct map to access a nearby PTE and (2) loading a direct mapping into the TLB involves walking only 2 or 3 levels of the page table instead of 4. Revision Changes Path 1.604 +1 -1 src/sys/amd64/amd64/pmap.c