KVM: switch to get_user_pages_fast

Convert gfn_to_pfn to use get_user_pages_fast, which can do lockless
pagetable lookups on x86. Kernel compilation on 4-way guest is 3.7%
faster on VMX.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 0 insertions, 2 deletions

diff --git a/arch/powerpc/kvm/44x_tlb.c b/arch/powerpc/kvm/44x_tlb.c
index 7b11fd7be542..2e227a412bc2 100644
--- a/arch/powerpc/kvm/44x_tlb.c
+++ b/arch/powerpc/kvm/44x_tlb.c
@@ -147,9 +147,7 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
         stlbe = &vcpu->arch.shadow_tlb[victim];
 
         /* Get reference to new page. */
-        down_read(&current->mm->mmap_sem);
         new_page = gfn_to_page(vcpu->kvm, gfn);
-        up_read(&current->mm->mmap_sem);
         if (is_error_page(new_page)) {
                 printk(KERN_ERR "Couldn't get guest page for gfn %lx!\n", gfn);
                 kvm_release_page_clean(new_page);