[PATCH 2/3] KVM: RISC-V: Use kvm_vcpu.srcu_idx, drop RISC-V's unnecessary copy

From: Sean Christopherson
Date: Thu Apr 14 2022 - 20:43:58 EST


Use the generic kvm_vcpu's srcu_idx instead of using an indentical field
in RISC-V's version of kvm_vcpu_arch. Generic KVM very intentionally
does not touch vcpu->srcu_idx, i.e. there's zero chance of running afoul
of common code.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/riscv/include/asm/kvm_host.h | 3 ---
arch/riscv/kvm/vcpu.c | 16 ++++++++--------
arch/riscv/kvm/vcpu_exit.c | 4 ++--
3 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index 78da839657e5..cd4bbcecb0fb 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -193,9 +193,6 @@ struct kvm_vcpu_arch {

/* Don't run the VCPU (blocked) */
bool pause;
-
- /* SRCU lock index for in-kernel run loop */
- int srcu_idx;
};

static inline void kvm_arch_hardware_unsetup(void) {}
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 6785aef4cbd4..2f1caf23eed4 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -724,13 +724,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
/* Mark this VCPU ran at least once */
vcpu->arch.ran_atleast_once = true;

- vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);

/* Process MMIO value returned from user-space */
if (run->exit_reason == KVM_EXIT_MMIO) {
ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run);
if (ret) {
- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
return ret;
}
}
@@ -739,13 +739,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
if (run->exit_reason == KVM_EXIT_RISCV_SBI) {
ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run);
if (ret) {
- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
return ret;
}
}

if (run->immediate_exit) {
- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
return -EINTR;
}

@@ -784,7 +784,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
*/
vcpu->mode = IN_GUEST_MODE;

- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
smp_mb__after_srcu_read_unlock();

/*
@@ -802,7 +802,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
vcpu->mode = OUTSIDE_GUEST_MODE;
local_irq_enable();
preempt_enable();
- vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
continue;
}

@@ -846,7 +846,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)

preempt_enable();

- vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);

ret = kvm_riscv_vcpu_exit(vcpu, run, &trap);
}
@@ -855,7 +855,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)

vcpu_put(vcpu);

- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);

return ret;
}
diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
index aa8af129e4bb..2d56faddb9d1 100644
--- a/arch/riscv/kvm/vcpu_exit.c
+++ b/arch/riscv/kvm/vcpu_exit.c
@@ -456,9 +456,9 @@ static int stage2_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run,
void kvm_riscv_vcpu_wfi(struct kvm_vcpu *vcpu)
{
if (!kvm_arch_vcpu_runnable(vcpu)) {
- srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx);
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
kvm_vcpu_halt(vcpu);
- vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
kvm_clear_request(KVM_REQ_UNHALT, vcpu);
}
}
--
2.36.0.rc0.470.gd361397f0d-goog