From a4ee1ca4a36e7857d90ae8c2b85f1bde9a042c10 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 23 Nov 2010 11:13:00 +0800 Subject: KVM: MMU: delay flush all tlbs on sync_page path Quote from Avi: | I don't think we need to flush immediately; set a "tlb dirty" bit somewhere | that is cleareded when we flush the tlb. kvm_mmu_notifier_invalidate_page() | can consult the bit and force a flush if set. Signed-off-by: Xiao Guangrong Signed-off-by: Marcelo Tosatti --- virt/kvm/kvm_main.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5156d458a84..ee99b77e445 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -168,8 +168,12 @@ static bool make_all_cpus_request(struct kvm *kvm, unsigned int req) void kvm_flush_remote_tlbs(struct kvm *kvm) { + int dirty_count = kvm->tlbs_dirty; + + smp_mb(); if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH)) ++kvm->stat.remote_tlb_flush; + cmpxchg(&kvm->tlbs_dirty, dirty_count, 0); } void kvm_reload_remote_mmus(struct kvm *kvm) @@ -249,7 +253,7 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); kvm->mmu_notifier_seq++; - need_tlb_flush = kvm_unmap_hva(kvm, address); + need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty; spin_unlock(&kvm->mmu_lock); srcu_read_unlock(&kvm->srcu, idx); @@ -293,6 +297,7 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, kvm->mmu_notifier_count++; for (; start < end; start += PAGE_SIZE) need_tlb_flush |= kvm_unmap_hva(kvm, start); + need_tlb_flush |= kvm->tlbs_dirty; spin_unlock(&kvm->mmu_lock); srcu_read_unlock(&kvm->srcu, idx); -- cgit v1.2.3