[PATCH 07/13] target/i386: Allow elision of kvm_enable_x2apic()

[Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>]

Call kvm_enabled() before kvm_enable_x2apic() to
let the compiler elide its call.

Suggested-by: Daniel Henrique Barboza <dbarboza@xxxxxxxxxxxxxxxx>
Signed-off-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
---
 hw/i386/intel_iommu.c      | 2 +-
 hw/i386/x86.c              | 2 +-
 target/i386/kvm/kvm-stub.c | 7 -------
 3 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 3ca71df369..c9961ef752 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -4053,7 +4053,7 @@ static bool vtd_decide_config(IntelIOMMUState *s, Error **errp)
             error_setg(errp, "eim=on requires accel=kvm,kernel-irqchip=split");
             return false;
         }
-        if (!kvm_enable_x2apic()) {
+        if (kvm_enabled() && !kvm_enable_x2apic()) {
             error_setg(errp, "eim=on requires support on the KVM side"
                              "(X2APIC_API, first shipped in v4.7)");
             return false;
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index a88a126123..d2920af792 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -136,7 +136,7 @@ void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
      * With KVM's in-kernel lapic: only if X2APIC API is enabled.
      */
     if (x86ms->apic_id_limit > 255 && !xen_enabled() &&
-        (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
+        kvm_enabled() && (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
         error_report("current -smp configuration requires kernel "
                      "irqchip and X2APIC API support.");
         exit(EXIT_FAILURE);
diff --git a/target/i386/kvm/kvm-stub.c b/target/i386/kvm/kvm-stub.c
index f985d9a1d3..62cccebee4 100644
--- a/target/i386/kvm/kvm-stub.c
+++ b/target/i386/kvm/kvm-stub.c
@@ -12,13 +12,6 @@
 #include "qemu/osdep.h"
 #include "kvm_i386.h"
 
-#ifndef __OPTIMIZE__
-bool kvm_enable_x2apic(void)
-{
-    return false;
-}
-#endif
-
 bool kvm_hv_vpindex_settable(void)
 {
     return false;
-- 
2.41.0