From owner-svn-src-all@FreeBSD.ORG Sat May 17 14:35:18 2014 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 91D2B986; Sat, 17 May 2014 14:35:18 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 7F037275C; Sat, 17 May 2014 14:35:18 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.8/8.14.8) with ESMTP id s4HEZI35051311; Sat, 17 May 2014 14:35:18 GMT (envelope-from alc@svn.freebsd.org) Received: (from alc@localhost) by svn.freebsd.org (8.14.8/8.14.8/Submit) id s4HEZIHp051310; Sat, 17 May 2014 14:35:18 GMT (envelope-from alc@svn.freebsd.org) Message-Id: <201405171435.s4HEZIHp051310@svn.freebsd.org> From: Alan Cox Date: Sat, 17 May 2014 14:35:18 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r266315 - stable/10/sys/vm X-SVN-Group: stable-10 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18 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: Sat, 17 May 2014 14:35:18 -0000 Author: alc Date: Sat May 17 14:35:18 2014 New Revision: 266315 URL: http://svnweb.freebsd.org/changeset/base/266315 Log: MFC r265850 About 9% of the pmap_protect() calls being performed by vm_map_copy_entry() are unnecessary. Eliminate the unnecessary calls. Modified: stable/10/sys/vm/vm_map.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/vm/vm_map.c ============================================================================== --- stable/10/sys/vm/vm_map.c Sat May 17 14:22:37 2014 (r266314) +++ stable/10/sys/vm/vm_map.c Sat May 17 14:35:18 2014 (r266315) @@ -3023,7 +3023,8 @@ vm_map_copy_entry( * If the source entry is marked needs_copy, it is already * write-protected. */ - if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { + if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0 && + (src_entry->protection & VM_PROT_WRITE) != 0) { pmap_protect(src_map->pmap, src_entry->start, src_entry->end,