diff options
| author | Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> | 2013-01-08 19:46:07 +0900 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2013-01-14 11:14:09 +0200 |
| commit | b34cb590fb099f7929dd78d9464b70319ee12a98 (patch) | |
| tree | 2af7587ccd189b568129b9e2eccebdcb5cd690d3 /arch/x86/kvm/x86.c | |
| parent | e12091ce7bdd3c82fa392a868d1bdccecee655d5 (diff) | |
KVM: Make kvm_mmu_change_mmu_pages() take mmu_lock by itself
No reason to make callers take mmu_lock since we do not need to protect
kvm_mmu_change_mmu_pages() and kvm_mmu_slot_remove_write_access()
together by mmu_lock in kvm_arch_commit_memory_region(): the former
calls kvm_mmu_commit_zap_page() and flushes TLBs by itself.
Note: we do not need to protect kvm->arch.n_requested_mmu_pages by
mmu_lock as can be seen from the fact that it is read locklessly.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index add5e480196..080bbdcbf2e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3270,12 +3270,10 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, return -EINVAL; mutex_lock(&kvm->slots_lock); - spin_lock(&kvm->mmu_lock); kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages); kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages; - spin_unlock(&kvm->mmu_lock); mutex_unlock(&kvm->slots_lock); return 0; } @@ -6894,7 +6892,6 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, if (!kvm->arch.n_requested_mmu_pages) nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm); - spin_lock(&kvm->mmu_lock); if (nr_mmu_pages) kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages); /* @@ -6902,9 +6899,11 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, * Existing largepage mappings are destroyed here and new ones will * not be created until the end of the logging. */ - if (npages && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES)) + if (npages && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES)) { + spin_lock(&kvm->mmu_lock); kvm_mmu_slot_remove_write_access(kvm, mem->slot); - spin_unlock(&kvm->mmu_lock); + spin_unlock(&kvm->mmu_lock); + } /* * If memory slot is created, or moved, we need to clear all * mmio sptes. |