vmm(4): bump vmclear spinout [vmx 1/3]

[Dave Voutila]

Smallest of the VMX/VMCS stability diffs. This bumps the spinout to be
the same number of ticks used by the mplock debug. This is needed on
older/slower hosts.

ok?

-dv

diff e8c587551f20ba6fdaa0f483ea768aade9f66f7d 
981a8cfd4e1dfe412e9c72fb5b47e7e46813bfbb
blob - a7b21ec75899c81f076143fbe59f14279334ea09
blob + e335a1dc5e8a400b4bbf49cac2ec8853dffcdae3
--- sys/arch/amd64/amd64/vmm.c
+++ sys/arch/amd64/amd64/vmm.c
@@ -1373,7 +1373,7 @@ vmclear_on_cpu(struct cpu_info *ci)
 static int
 vmx_remote_vmclear(struct cpu_info *ci, struct vcpu *vcpu)
 {
-       int ret = 0, nticks = 100000;
+       int ret = 0, nticks = 200000000;

        mtx_enter(&ci->ci_vmcs_mtx);
        atomic_swap_ulong(&ci->ci_vmcs_pa, vcpu->vc_control_pa);