On 9/4/23 14:43, Philippe Mathieu-Daudé wrote:
> Call kvm_enabled() before kvm_enable_x2apic() to
> let the compiler elide its call.
>
> Suggested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> 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())) {
This "!xen && kvm" expression can be simplified.
I am queuing the series with this squashed in:
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index d2920af792d..3e86cf3060f 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -129,14 +129,11 @@ 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() &&
- kvm_enabled() && (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
+ 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.");
exit(EXIT_FAILURE);
Paolo
> 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;