From patchwork Fri Jul 16 03:30:18 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 112368 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o6G3YcZL018771 for ; Fri, 16 Jul 2010 03:34:38 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935560Ab0GPDeT (ORCPT ); Thu, 15 Jul 2010 23:34:19 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:55849 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S935497Ab0GPDeS (ORCPT ); Thu, 15 Jul 2010 23:34:18 -0400 Received: from tang.cn.fujitsu.com (tang.cn.fujitsu.com [10.167.250.3]) by song.cn.fujitsu.com (Postfix) with ESMTP id 27E6717016F; Fri, 16 Jul 2010 11:34:17 +0800 (CST) Received: from fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id o6G3VUR1003577; Fri, 16 Jul 2010 11:31:30 +0800 Received: from [10.167.141.99] (unknown [10.167.141.99]) by fnst.cn.fujitsu.com (Postfix) with ESMTPA id F2FC910C1C0; Fri, 16 Jul 2010 11:34:40 +0800 (CST) Message-ID: <4C3FD24A.9020605@cn.fujitsu.com> Date: Fri, 16 Jul 2010 11:30:18 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM list Subject: [PATCH v2 6/6] KVM: MMU: using __xchg_spte more smarter References: <4C3FCFD7.5070005@cn.fujitsu.com> <4C3FD1C9.5010909@cn.fujitsu.com> In-Reply-To: <4C3FD1C9.5010909@cn.fujitsu.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 16 Jul 2010 03:34:38 +0000 (UTC) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index fb3ae54..71e9268 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -682,9 +682,14 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) static void set_spte_track_bits(u64 *sptep, u64 new_spte) { pfn_t pfn; - u64 old_spte; + u64 old_spte = *sptep; + + if (!shadow_accessed_mask || !is_shadow_present_pte(old_spte) || + old_spte & shadow_accessed_mask) { + __set_spte(sptep, new_spte); + } else + old_spte = __xchg_spte(sptep, new_spte); - old_spte = __xchg_spte(sptep, new_spte); if (!is_rmap_spte(old_spte)) return; pfn = spte_to_pfn(old_spte);