From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: [PATCH v2 12/22] KVM: MMU: split kvm_mmu_free_page Date: Wed, 22 Jun 2011 22:32:55 +0800 Message-ID: <4E01FD17.3020106@cn.fujitsu.com> References: <4E01FBC9.3020009@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , LKML , KVM To: Avi Kivity Return-path: In-Reply-To: <4E01FBC9.3020009@cn.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Split kvm_mmu_free_page to kvm_mmu_isolate_page and kvm_mmu_free_page One is used to remove the page from cache under mmu lock and the other is used to free page table out of mmu lock Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 21 ++++++++++++++++++--- 1 files changed, 18 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8233aba..c6fabf0 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1039,14 +1039,28 @@ 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); } @@ -1678,6 +1692,7 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm, do { sp = list_first_entry(invalid_list, struct kvm_mmu_page, link); WARN_ON(!sp->role.invalid || sp->root_count); + kvm_mmu_isolate_page(sp); kvm_mmu_free_page(sp); } while (!list_empty(invalid_list)); -- 1.7.5.4