[PATCH kvmtool 3/9] arm: Get rid of the ARM_VCPU_FEATURE_FLAGS() macro

Alexandru Elisei alexandru.elisei at arm.com
Mon Nov 15 08:56:59 PST 2021


The ARM_VCPU_FEATURE_FLAGS() macro sets a feature bit in a rather
convoluted way: if cpu_id is 0, then bit KVM_ARM_VCPU_POWER_OFF is 0,
otherwise is set to 1. There's really no need for this indirection,
especially considering that the macro has been changed to return the same
value for both the arm and arm64 architectures. Replace it with a simple
conditional statement in kvm_cpu__arch_init(), which makes it clearer to
understand.

Signed-off-by: Alexandru Elisei <alexandru.elisei at arm.com>
---
 arm/aarch32/include/kvm/kvm-cpu-arch.h | 4 ----
 arm/aarch64/include/kvm/kvm-cpu-arch.h | 4 ----
 arm/kvm-cpu.c                          | 6 +++++-
 3 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/arm/aarch32/include/kvm/kvm-cpu-arch.h b/arm/aarch32/include/kvm/kvm-cpu-arch.h
index 780e0e2f0934..fc9aef9f6320 100644
--- a/arm/aarch32/include/kvm/kvm-cpu-arch.h
+++ b/arm/aarch32/include/kvm/kvm-cpu-arch.h
@@ -5,10 +5,6 @@
 
 #include "arm-common/kvm-cpu-arch.h"
 
-#define ARM_VCPU_FEATURE_FLAGS(kvm, cpuid)	{			\
-	[0] = (!!(cpuid) << KVM_ARM_VCPU_POWER_OFF),			\
-}
-
 #define ARM_MPIDR_HWID_BITMASK	0xFFFFFF
 #define ARM_CPU_ID		0, 0, 0
 #define ARM_CPU_ID_MPIDR	5
diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h
index 016cf5b2b9ea..17b80493e2c0 100644
--- a/arm/aarch64/include/kvm/kvm-cpu-arch.h
+++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h
@@ -5,10 +5,6 @@
 
 #include "arm-common/kvm-cpu-arch.h"
 
-#define ARM_VCPU_FEATURE_FLAGS(kvm, cpuid)	{				\
-	[0] = (!!(cpuid) << KVM_ARM_VCPU_POWER_OFF),				\
-}
-
 #define ARM_MPIDR_HWID_BITMASK	0xFF00FFFFFFUL
 #define ARM_CPU_ID		3, 0, 0, 0
 #define ARM_CPU_ID_MPIDR	5
diff --git a/arm/kvm-cpu.c b/arm/kvm-cpu.c
index 554414f81b7a..62177ea73f82 100644
--- a/arm/kvm-cpu.c
+++ b/arm/kvm-cpu.c
@@ -43,7 +43,7 @@ struct kvm_cpu *kvm_cpu__arch_init(struct kvm *kvm, unsigned long cpu_id)
 	unsigned int i;
 	struct kvm_vcpu_init preferred_init;
 	struct kvm_vcpu_init vcpu_init = {
-		.features = ARM_VCPU_FEATURE_FLAGS(kvm, cpu_id)
+		.features = {},
 	};
 
 	vcpu = calloc(1, sizeof(struct kvm_cpu));
@@ -63,6 +63,10 @@ struct kvm_cpu *kvm_cpu__arch_init(struct kvm *kvm, unsigned long cpu_id)
 	if (vcpu->kvm_run == MAP_FAILED)
 		die("unable to mmap vcpu fd");
 
+	/* VCPU 0 is the boot CPU, the others start in a poweroff state. */
+	if (cpu_id > 0)
+		vcpu_init.features[0] |= (1UL << KVM_ARM_VCPU_POWER_OFF);
+
 	/* Set KVM_ARM_VCPU_PSCI_0_2 if available */
 	if (kvm__supports_extension(kvm, KVM_CAP_ARM_PSCI_0_2)) {
 		vcpu_init.features[0] |= (1UL << KVM_ARM_VCPU_PSCI_0_2);
-- 
2.31.1




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