From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754340Ab3EPVOZ (ORCPT ); Thu, 16 May 2013 17:14:25 -0400 Received: from e28smtp03.in.ibm.com ([122.248.162.3]:48914 "EHLO e28smtp03.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754099Ab3EPVNW (ORCPT ); Thu, 16 May 2013 17:13:22 -0400 From: Xiao Guangrong To: gleb@redhat.com Cc: avi.kivity@gmail.com, mtosatti@redhat.com, pbonzini@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Xiao Guangrong Subject: [PATCH v6 4/7] KVM: MMU: zap pages in batch Date: Fri, 17 May 2013 05:12:59 +0800 Message-Id: <1368738782-18649-5-git-send-email-xiaoguangrong@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <1368738782-18649-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> References: <1368738782-18649-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13051621-3864-0000-0000-0000082F48F0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Zap at lease 10 pages before releasing mmu-lock to reduce the overload caused by requiring lock [ It improves kernel building 0.6% ~ 1% ] Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 14 ++++++++++++-- 1 files changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 891ad2c..7ad0e50 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4207,14 +4207,18 @@ restart: spin_unlock(&kvm->mmu_lock); } +#define BATCH_ZAP_PAGES 10 static void kvm_zap_obsolete_pages(struct kvm *kvm) { struct kvm_mmu_page *sp, *node; LIST_HEAD(invalid_list); + int batch = 0; restart: list_for_each_entry_safe_reverse(sp, node, &kvm->arch.active_mmu_pages, link) { + int ret; + /* * No obsolete page exists before new created page since * active_mmu_pages is the FIFO list. @@ -4252,10 +4256,16 @@ restart: * Need not flush tlb since we only zap the sp with invalid * generation number. */ - if (cond_resched_lock(&kvm->mmu_lock)) + if ((batch >= BATCH_ZAP_PAGES) && + cond_resched_lock(&kvm->mmu_lock)) { + batch = 0; goto restart; + } - if (kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list)) + ret = kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list); + batch += ret; + + if (ret) goto restart; } -- 1.7.7.6