[PATCH v2] powerpc: select ARCH_HAS_MEMBARRIER_SYNC_CORE

[Andreas Schwab]

On Jul 15 2020, Nicholas Piggin wrote:

> diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h
> index 54a98ef7d7fe..071d7ccb830f 100644
> --- a/arch/powerpc/include/asm/exception-64e.h
> +++ b/arch/powerpc/include/asm/exception-64e.h
> @@ -204,7 +204,11 @@ exc_##label##_book3e:
>  	LOAD_REG_ADDR(r3,interrupt_base_book3e);\
>  	ori	r3,r3,vector_offset at l;		\
>  	mtspr	SPRN_IVOR##vector_number,r3;
> -
> +/*
> + * powerpc relies on return from interrupt/syscall being context synchronising
> + * (which rfi is) to support ARCH_HAS_MEMBARRIER_SYNC_CORE without additional
> + * additional synchronisation instructions.

s/additonal//

Andreas.

-- 
Andreas Schwab, schwab at linux-m68k.org
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