diff mbox series

[PULL,43/51] target/i386: Allow elision of kvm_enable_x2apic()

Message ID 20230907130004.500601-44-pbonzini@redhat.com
State Accepted
Commit 9926cf34de5fa15da1d58e809692b5c7ccf72ec5
Headers show
Series None | expand

Commit Message

Paolo Bonzini Sept. 7, 2023, 12:59 p.m. UTC 
From: Philippe Mathieu-Daudé <philmd@linaro.org>

Call kvm_enabled() before kvm_enable_x2apic() to let the compiler elide
its call.  Cleanup the code by simplifying "!xen_enabled() &&
kvm_enabled()" to just "kvm_enabled()".

Suggested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230904124325.79040-8-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/i386/intel_iommu.c      | 2 +-
 hw/i386/x86.c              | 9 +++------
 target/i386/kvm/kvm-stub.c | 7 -------
 3 files changed, 4 insertions(+), 14 deletions(-)
diff mbox series

Patch

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 3ca71df3693..c9961ef752c 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 a88a126123b..3e86cf3060f 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -129,13 +129,10 @@  void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
                                                       ms->smp.max_cpus - 1) + 1;
 
     /*
-     * Can we support APIC ID 255 or higher?
-     *
-     * Under Xen: yes.
-     * With userspace emulated lapic: no
-     * With KVM's in-kernel lapic: only if X2APIC API is enabled.
+     * Can we support APIC ID 255 or higher?  With KVM, that requires
+     * both in-kernel lapic and X2APIC userspace API.
      */
-    if (x86ms->apic_id_limit > 255 && !xen_enabled() &&
+    if (x86ms->apic_id_limit > 255 && kvm_enabled() &&
         (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
         error_report("current -smp configuration requires kernel "
                      "irqchip and X2APIC API support.");
diff --git a/target/i386/kvm/kvm-stub.c b/target/i386/kvm/kvm-stub.c
index f985d9a1d39..62cccebee4f 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;