Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935743Ab3IEKbV (ORCPT ); Thu, 5 Sep 2013 06:31:21 -0400 Received: from e28smtp08.in.ibm.com ([122.248.162.8]:52194 "EHLO e28smtp08.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935728Ab3IEK3s (ORCPT ); Thu, 5 Sep 2013 06:29:48 -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 v2 11/15] KVM: MMU: reintroduce kvm_mmu_isolate_page() Date: Thu, 5 Sep 2013 18:29:14 +0800 Message-Id: <1378376958-27252-12-git-send-email-xiaoguangrong@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1378376958-27252-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> References: <1378376958-27252-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13090510-2000-0000-0000-00000D9913FD Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1886 Lines: 62 It was removed by commit 834be0d83. Now we will need it to do lockless shadow page walking protected by rcu, so reintroduce it Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index fe80019..2bf450a 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1675,14 +1675,30 @@ static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr) percpu_counter_add(&kvm_total_used_mmu_pages, nr); } -static void kvm_mmu_free_page(struct kvm_mmu_page *sp) +/* + * Remove the sp from shadow page cache, after call it, + * we can not find this sp from the cache, and the shadow + * page table is still valid. + * + * It should be under the protection of mmu lock. + */ +static void kvm_mmu_isolate_page(struct kvm_mmu_page *sp) { ASSERT(is_empty_shadow_page(sp->spt)); + hlist_del(&sp->hash_link); - list_del(&sp->link); - free_page((unsigned long)sp->spt); if (!sp->role.direct) free_page((unsigned long)sp->gfns); +} + +/* + * Free the shadow page table and the sp, we can do it + * out of the protection of mmu lock. + */ +static void kvm_mmu_free_page(struct kvm_mmu_page *sp) +{ + list_del(&sp->link); + free_page((unsigned long)sp->spt); kmem_cache_free(mmu_page_header_cache, sp); } @@ -2361,6 +2377,7 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm, list_for_each_entry_safe(sp, nsp, invalid_list, link) { WARN_ON(!sp->role.invalid || sp->root_count); + kvm_mmu_isolate_page(sp); kvm_mmu_free_page(sp); } } -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/