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Subject: Re: [PATCH] MIPS: include: Mark __xchg as __always_inline
To:     Thomas Bogendoerfer <tbogendoerfer@suse.de>,
        Ralf Baechle <ralf@linux-mips.org>,
        Paul Burton <paul.burton@mips.com>,
        James Hogan <jhogan@kernel.org>, linux-mips@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jiaxun Yang <jiaxun.yang@flygoat.com>
References: <20191009100600.10572-1-tbogendoerfer@suse.de>
From:   =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= <f4bug@amsat.org>
Message-ID: <a685a8fe-7cd9-7d94-54c8-3b6e133cfd74@amsat.org>
Date:   Wed, 9 Oct 2019 14:43:35 +0200
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On 10/9/19 12:06 PM, Thomas Bogendoerfer wrote:
> Commit ac7c3e4ff401 ("compiler: enable CONFIG_OPTIMIZE_INLINING
> forcibly") allows compiler to uninline functions marked as 'inline'.
> In cace of __xchg this would cause to reference function

Typo: "in case of"

> __xchg_called_with_bad_pointer, which is an error case
> for catching bugs and will not happen for correct code, if
> __xchg is inlined.
> 

Ah, this is the equivalent of ARM commit 920fdab7b3c.

Maybe add:

Fixes: ac7c3e4ff401

> Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
> ---
>   arch/mips/include/asm/cmpxchg.h | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/mips/include/asm/cmpxchg.h b/arch/mips/include/asm/cmpxchg.h
> index 012dcf7046ad..f6136871561d 100644
> --- a/arch/mips/include/asm/cmpxchg.h
> +++ b/arch/mips/include/asm/cmpxchg.h
> @@ -77,8 +77,8 @@ extern unsigned long __xchg_called_with_bad_pointer(void)
>   extern unsigned long __xchg_small(volatile void *ptr, unsigned long val,
>   				  unsigned int size);
>   
> -static inline unsigned long __xchg(volatile void *ptr, unsigned long x,
> -				   int size)
> +static __always_inline
> +unsigned long __xchg(volatile void *ptr, unsigned long x, int size)
>   {
>   	switch (size) {
>   	case 1:
> 

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>