Re: [PATCH 08/13] kvm/powerpc: Move guest enter/exit down into subarch-specific code

[Marcelo Tosatti <mtosatti@redhat.com>]

On Wed, May 11, 2011 at 08:43:31PM +1000, Paul Mackerras wrote:
> >From 964ee93b2d728e4fb16ae66eaceb6e912bf114ad Mon Sep 17 00:00:00 2001
> From: Paul Mackerras <paulus@samba.org>
> Date: Tue, 10 May 2011 22:23:18 +1000
> Subject: [PATCH 08/13] kvm/powerpc: Move guest enter/exit down into
>  subarch-specific code
> 
> Instead of doing the kvm_guest_enter/exit() and local_irq_dis/enable()
> calls in powerpc.c, this moves them down into the subarch-specific
> book3s_pr.c and booke.c.  This eliminates an extra local_irq_enable()
> call in book3s_pr.c, and will be needed for when we do SMT4 guest
> support in the book3s hypervisor mode code.
> 
> Signed-off-by: Paul Mackerras <paulus@samba.org>
> ---
>  arch/powerpc/include/asm/kvm_ppc.h   |    1 +
>  arch/powerpc/kvm/book3s_interrupts.S |    2 +-
>  arch/powerpc/kvm/book3s_pr.c         |   12 ++++++------
>  arch/powerpc/kvm/booke.c             |   13 +++++++++++++
>  arch/powerpc/kvm/powerpc.c           |    6 +-----
>  5 files changed, 22 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
> index f3c218a..3210911 100644
> --- a/arch/powerpc/include/asm/kvm_ppc.h
> +++ b/arch/powerpc/include/asm/kvm_ppc.h
> @@ -42,6 +42,7 @@ enum emulation_result {
>  	EMULATE_AGAIN,        /* something went wrong. go again */
>  };
>  
> +extern int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
>  extern int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
>  extern char kvmppc_handlers_start[];
>  extern unsigned long kvmppc_handler_len;
> diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S
> index 2f0bc92..8c5e0e1 100644
> --- a/arch/powerpc/kvm/book3s_interrupts.S
> +++ b/arch/powerpc/kvm/book3s_interrupts.S
> @@ -85,7 +85,7 @@
>   *  r3: kvm_run pointer
>   *  r4: vcpu pointer
>   */
> -_GLOBAL(__kvmppc_vcpu_entry)
> +_GLOBAL(__kvmppc_vcpu_run)
>  
>  kvm_start_entry:
>  	/* Write correct stack frame */
> diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
> index 08cedf0..f769915 100644
> --- a/arch/powerpc/kvm/book3s_pr.c
> +++ b/arch/powerpc/kvm/book3s_pr.c
> @@ -891,8 +891,7 @@ void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu)
>  	vfree(vcpu_book3s);
>  }
>  
> -extern int __kvmppc_vcpu_entry(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
> -int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
> +int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
>  {
>  	int ret;
>  	double fpr[32][TS_FPRWIDTH];
> @@ -944,14 +943,15 @@ int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
>  	/* Remember the MSR with disabled extensions */
>  	ext_msr = current->thread.regs->msr;
>  
> -	/* XXX we get called with irq disabled - change that! */
> -	local_irq_enable();
> -
>  	/* Preload FPU if it's enabled */
>  	if (vcpu->arch.shared->msr & MSR_FP)
>  		kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP);
>  
> -	ret = __kvmppc_vcpu_entry(kvm_run, vcpu);
> +	kvm_guest_enter();


kvm_guest_enter should run with interrupts disabled.