From owner-svn-src-projects@FreeBSD.ORG Tue Sep 24 18:46:18 2013 Return-Path: Delivered-To: svn-src-projects@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 ESMTP id D784AF70; Tue, 24 Sep 2013 18:46:18 +0000 (UTC) (envelope-from neel@FreeBSD.org) 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)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id C4D532158; Tue, 24 Sep 2013 18:46:18 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id r8OIkIJR071752; Tue, 24 Sep 2013 18:46:18 GMT (envelope-from neel@svn.freebsd.org) Received: (from neel@localhost) by svn.freebsd.org (8.14.7/8.14.5/Submit) id r8OIkIwh071751; Tue, 24 Sep 2013 18:46:18 GMT (envelope-from neel@svn.freebsd.org) Message-Id: <201309241846.r8OIkIwh071751@svn.freebsd.org> From: Neel Natu Date: Tue, 24 Sep 2013 18:46:18 +0000 (UTC) To: src-committers@freebsd.org, svn-src-projects@freebsd.org Subject: svn commit: r255858 - projects/bhyve_npt_pmap/sys/amd64/vmm X-SVN-Group: projects MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-projects@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the src " projects" tree" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Sep 2013 18:46:18 -0000 Author: neel Date: Tue Sep 24 18:46:18 2013 New Revision: 255858 URL: http://svnweb.freebsd.org/changeset/base/255858 Log: Use 'vm_fault_quick_hold_pages()' to hold pages belonging to the guest address space before accessing them in the host. We used to use 'vm_fault_hold()' prior to this change. This worked correctly but had the drawback that it would 'pmap_enter()' the gpa->hpa mapping unconditionally in the nested pmap. This in turn would cause unnecessary superpage demotions and promotions if the 'gpa' happened to be a superpage mapping. Discussed with: alc@, kib@ Modified: projects/bhyve_npt_pmap/sys/amd64/vmm/vmm.c Modified: projects/bhyve_npt_pmap/sys/amd64/vmm/vmm.c ============================================================================== --- projects/bhyve_npt_pmap/sys/amd64/vmm/vmm.c Tue Sep 24 18:24:01 2013 (r255857) +++ projects/bhyve_npt_pmap/sys/amd64/vmm/vmm.c Tue Sep 24 18:46:18 2013 (r255858) @@ -602,17 +602,17 @@ void * vm_gpa_hold(struct vm *vm, vm_paddr_t gpa, size_t len, int reqprot, void **cookie) { - int rv, pageoff; + int count, pageoff; vm_page_t m; pageoff = gpa & PAGE_MASK; if (len > PAGE_SIZE - pageoff) panic("vm_gpa_hold: invalid gpa/len: 0x%016lx/%lu", gpa, len); - rv = vm_fault_hold(&vm->vmspace->vm_map, trunc_page(gpa), reqprot, - VM_FAULT_NORMAL, &m); + count = vm_fault_quick_hold_pages(&vm->vmspace->vm_map, + trunc_page(gpa), PAGE_SIZE, reqprot, &m, 1); - if (rv == KERN_SUCCESS) { + if (count == 1) { *cookie = m; return ((void *)(PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)) + pageoff)); } else {