commit f78e0e2ee498e8f847500b565792c7d7634dcf54
author Sheng Yang <sheng.yang@intel.com> Mon Oct 29 09:40:42 2007 +0800
committer Avi Kivity <avi@qumranet.com> Wed Jan 30 17:52:58 2008 +0200
tree dfd8f35883b40939a1ec013e27e6303af06d3e77
parent a03490ed29d2771c675d4d9c0ffe22e19a1757f3

KVM: VMX: Enable memory mapped TPR shadow (FlexPriority)

This patch based on CR8/TPR patch, and enable the TPR shadow (FlexPriority)
for 32bit Windows.  Since TPR is accessed very frequently by 32bit
Windows, especially SMP guest, with FlexPriority enabled, we saw significant
performance gain.

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

drivers/kvm/kvm_main.c

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 8f71257..ac5ed00 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -362,10 +362,12 @@
  * space.
  *
  * Discontiguous memory is allowed, mostly for framebuffers.
+ *
+ * Must be called holding kvm->lock.
  */
-int kvm_set_memory_region(struct kvm *kvm,
-			  struct kvm_userspace_memory_region *mem,
-			  int user_alloc)
+int __kvm_set_memory_region(struct kvm *kvm,
+			    struct kvm_userspace_memory_region *mem,
+			    int user_alloc)
 {
 	int r;
 	gfn_t base_gfn;
@@ -392,8 +394,6 @@
 	if (!npages)
 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 
-	mutex_lock(&kvm->lock);
-
 	new = old = *memslot;
 
 	new.base_gfn = base_gfn;
@@ -403,7 +403,7 @@
 	/* Disallow changing a memory slot's size. */
 	r = -EINVAL;
 	if (npages && old.npages && npages != old.npages)
-		goto out_unlock;
+		goto out_free;
 
 	/* Check for overlaps */
 	r = -EEXIST;
@@ -414,7 +414,7 @@
 			continue;
 		if (!((base_gfn + npages <= s->base_gfn) ||
 		      (base_gfn >= s->base_gfn + s->npages)))
-			goto out_unlock;
+			goto out_free;
 	}
 
 	/* Free page dirty bitmap if unneeded */
@@ -428,7 +428,7 @@
 		new.rmap = vmalloc(npages * sizeof(struct page *));
 
 		if (!new.rmap)
-			goto out_unlock;
+			goto out_free;
 
 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
 
@@ -445,7 +445,7 @@
 			up_write(&current->mm->mmap_sem);
 
 			if (IS_ERR((void *)new.userspace_addr))
-				goto out_unlock;
+				goto out_free;
 		}
 	} else {
 		if (!old.user_alloc && old.rmap) {
@@ -468,7 +468,7 @@
 
 		new.dirty_bitmap = vmalloc(dirty_bytes);
 		if (!new.dirty_bitmap)
-			goto out_unlock;
+			goto out_free;
 		memset(new.dirty_bitmap, 0, dirty_bytes);
 	}
 
@@ -498,18 +498,28 @@
 	kvm_mmu_slot_remove_write_access(kvm, mem->slot);
 	kvm_flush_remote_tlbs(kvm);
 
-	mutex_unlock(&kvm->lock);
-
 	kvm_free_physmem_slot(&old, &new);
 	return 0;
 
-out_unlock:
-	mutex_unlock(&kvm->lock);
+out_free:
 	kvm_free_physmem_slot(&new, &old);
 out:
 	return r;
 
 }
+EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
+
+int kvm_set_memory_region(struct kvm *kvm,
+			  struct kvm_userspace_memory_region *mem,
+			  int user_alloc)
+{
+	int r;
+
+	mutex_lock(&kvm->lock);
+	r = __kvm_set_memory_region(kvm, mem, user_alloc);
+	mutex_unlock(&kvm->lock);
+	return r;
+}
 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 
 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
@@ -888,14 +898,21 @@
 		memcpy(val, vcpu->mmio_data, bytes);
 		vcpu->mmio_read_completed = 0;
 		return X86EMUL_CONTINUE;
-	} else if (emulator_read_std(addr, val, bytes, vcpu)
-		   == X86EMUL_CONTINUE)
-		return X86EMUL_CONTINUE;
+	}
 
 	gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);
+
+	/* For APIC access vmexit */
+	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+		goto mmio;
+
+	if (emulator_read_std(addr, val, bytes, vcpu)
+			== X86EMUL_CONTINUE)
+		return X86EMUL_CONTINUE;
 	if (gpa == UNMAPPED_GVA)
 		return X86EMUL_PROPAGATE_FAULT;
 
+mmio:
 	/*
 	 * Is this MMIO handled locally?
 	 */
@@ -938,9 +955,14 @@
 		return X86EMUL_PROPAGATE_FAULT;
 	}
 
+	/* For APIC access vmexit */
+	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+		goto mmio;
+
 	if (emulator_write_phys(vcpu, gpa, val, bytes))
 		return X86EMUL_CONTINUE;
 
+mmio:
 	/*
 	 * Is this MMIO handled locally?
 	 */