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| author | Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> | 2010-11-23 11:13:00 +0800 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-01-12 11:29:51 +0200 |
| commit | a4ee1ca4a36e7857d90ae8c2b85f1bde9a042c10 (patch) | |
| tree | 29707dd004ef14df318ac35321b95ac62570fc99 /virt | |
| parent | 407c61c6bd6a51b56d02f8bbad8aadf19db8c7b5 (diff) | |
| download | lwn-a4ee1ca4a36e7857d90ae8c2b85f1bde9a042c10.tar.gz lwn-a4ee1ca4a36e7857d90ae8c2b85f1bde9a042c10.zip | |
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 <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/kvm_main.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5156d458a84d..ee99b77e4451 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); |