KVM: MMU: Coalesce remote tlb flushes
Host side TLB flush can be merged together if multiple
spte need to be write-protected.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 401eb7c..9a57e1a 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -513,6 +513,7 @@
{
unsigned long *rmapp;
u64 *spte;
+ int write_protected = 0;
gfn = unalias_gfn(kvm, gfn);
rmapp = gfn_to_rmap(kvm, gfn);
@@ -522,11 +523,14 @@
BUG_ON(!spte);
BUG_ON(!(*spte & PT_PRESENT_MASK));
rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte);
- if (is_writeble_pte(*spte))
+ if (is_writeble_pte(*spte)) {
set_shadow_pte(spte, *spte & ~PT_WRITABLE_MASK);
- kvm_flush_remote_tlbs(kvm);
+ write_protected = 1;
+ }
spte = rmap_next(kvm, rmapp, spte);
}
+ if (write_protected)
+ kvm_flush_remote_tlbs(kvm);
}
#ifdef MMU_DEBUG