[PATCH v2 3/3] KVM: x86: simplify kvm_mwait_in_guest()

From: Radim KrÄmÃÅ
Date: Wed Nov 29 2017 - 16:24:50 EST


If Intel/AMD implements MWAIT, we expect that it works well and only
reject known bugs; no reason to do it the other way around for minor
vendors. (Not that they are relevant ATM.)

This allows further simplification of kvm_mwait_in_guest().
And use boot_cpu_has() instead of "cpu_has(&boot_cpu_data," while at it.

Signed-off-by: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
---
arch/x86/kvm/x86.h | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index d15859ec5e92..c69f973111cb 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -265,18 +265,8 @@ static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec)

static inline bool kvm_mwait_in_guest(void)
{
- if (!cpu_has(&boot_cpu_data, X86_FEATURE_MWAIT))
- return false;
-
- switch (boot_cpu_data.x86_vendor) {
- case X86_VENDOR_AMD:
- /* All AMD CPUs have a working MWAIT implementation */
- return true;
- case X86_VENDOR_INTEL:
- return !boot_cpu_has_bug(X86_BUG_MONITOR);
- default:
- return false;
- }
+ return boot_cpu_has(X86_FEATURE_MWAIT) &&
+ !boot_cpu_has_bug(X86_BUG_MONITOR);
}

#endif
--
2.14.2