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| 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/mmu.c | |
| parent | e12091ce7bdd3c82fa392a868d1bdccecee655d5 (diff) | |
| download | lwn-b34cb590fb099f7929dd78d9464b70319ee12a98.tar.gz lwn-b34cb590fb099f7929dd78d9464b70319ee12a98.zip | |
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/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 9c1b2d6158bf..f5572804f594 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2143,6 +2143,8 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int goal_nr_mmu_pages) * change the value */ + spin_lock(&kvm->mmu_lock); + if (kvm->arch.n_used_mmu_pages > goal_nr_mmu_pages) { while (kvm->arch.n_used_mmu_pages > goal_nr_mmu_pages && !list_empty(&kvm->arch.active_mmu_pages)) { @@ -2157,6 +2159,8 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int goal_nr_mmu_pages) } kvm->arch.n_max_mmu_pages = goal_nr_mmu_pages; + + spin_unlock(&kvm->mmu_lock); } int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) |