Re: [kvm-unit-tests PATCH v3 01/27] x86: replace irq_{enable|disable}() with sti()/cli()

[Emanuele Giuseppe Esposito <eesposit@redhat.com>]

Am 22/11/2022 um 17:11 schrieb Maxim Levitsky:
> This removes a layer of indirection which is strictly
> speaking not needed since its x86 code anyway.
> 
> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> ---
>  lib/x86/processor.h       | 19 +++++-----------
>  lib/x86/smp.c             |  2 +-
>  x86/apic.c                |  2 +-
>  x86/asyncpf.c             |  6 ++---
>  x86/eventinj.c            | 22 +++++++++---------
>  x86/hyperv_connections.c  |  2 +-
>  x86/hyperv_stimer.c       |  4 ++--
>  x86/hyperv_synic.c        |  6 ++---
>  x86/intel-iommu.c         |  2 +-
>  x86/ioapic.c              | 14 ++++++------
>  x86/pmu.c                 |  4 ++--
>  x86/svm.c                 |  4 ++--
>  x86/svm_tests.c           | 48 +++++++++++++++++++--------------------
>  x86/taskswitch2.c         |  4 ++--
>  x86/tscdeadline_latency.c |  4 ++--
>  x86/vmexit.c              | 18 +++++++--------
>  x86/vmx_tests.c           | 42 +++++++++++++++++-----------------
>  17 files changed, 98 insertions(+), 105 deletions(-)
> 
> diff --git a/lib/x86/processor.h b/lib/x86/processor.h
> index 7a9e8c82..b89f6a7c 100644
> --- a/lib/x86/processor.h
> +++ b/lib/x86/processor.h
> @@ -653,11 +653,17 @@ static inline void pause(void)
>  	asm volatile ("pause");
>  }
>  
> +/* Disable interrupts as per x86 spec */
>  static inline void cli(void)
>  {
>  	asm volatile ("cli");
>  }
>  
> +/*
> + * Enable interrupts.
> + * Note that next instruction after sti will not have interrupts
> + * evaluated due to concept of 'interrupt shadow'
> + */
>  static inline void sti(void)
>  {
>  	asm volatile ("sti");
> @@ -732,19 +738,6 @@ static inline void wrtsc(u64 tsc)
>  	wrmsr(MSR_IA32_TSC, tsc);
>  }
>  
> -static inline void irq_disable(void)
> -{
> -	asm volatile("cli");
> -}
> -
> -/* Note that irq_enable() does not ensure an interrupt shadow due
> - * to the vagaries of compiler optimizations.  If you need the
> - * shadow, use a single asm with "sti" and the instruction after it.
Minor nitpick: instead of a new doc comment, why not use this same
above? Looks clearer to me.

Regardless,
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>