Re: [PATCH] arm64: armv8_deprecated: fix unused-function error

[Ren Zhijie]

在 2022/11/23 0:48, Mark Rutland 写道:
> On Tue, Nov 22, 2022 at 03:20:10AM +0000, Ren Zhijie wrote:
> > If CONFIG_SWP_EMULATION is not set and
> > CONFIG_CP15_BARRIER_EMULATION is not set,
> > aarch64-linux-gnu complained about unused-function :
> >
> > arch/arm64/kernel/armv8_deprecated.c:67:21: error: ‘aarch32_check_condition’ defined but not used [-Werror=unused-function]
> >   static unsigned int aarch32_check_condition(u32 opcode, u32 psr)
> >                       ^~~~~~~~~~~~~~~~~~~~~~~
> > cc1: all warnings being treated as errors
> >
> > To fix this error, warp the definition of
> > aarch32_check_condition() by defined(CONFIG_SWP_EMULATION) ||
> > defined(CONFIG_CP15_BARRIER_EMULATION)
> >
> > Fixes: 0c5f416219da ("arm64: armv8_deprecated: move aarch32 helper earlier")
> This also depends on building with additional options to turn warnings into
> errors, no?

No，i just run the normal command as follow:

make ARCH="arm64" CROSS_COMPILE="aarch64-linux-gnu-"

> > Signed-off-by: Ren Zhijie <renzhijie2@xxxxxxxxxx>
> > ---
> >   arch/arm64/kernel/armv8_deprecated.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c
> > index ed0788cf6bbb..3f29ceb6653a 100644
> > --- a/arch/arm64/kernel/armv8_deprecated.c
> > +++ b/arch/arm64/kernel/armv8_deprecated.c
> > @@ -64,6 +64,7 @@ struct insn_emulation {
> >   
> >   #define	ARM_OPCODE_CONDITION_UNCOND	0xf
> >   
> > +#if defined(CONFIG_SWP_EMULATION) || defined(CONFIG_CP15_BARRIER_EMULATION)
> >   static unsigned int aarch32_check_condition(u32 opcode, u32 psr)
> >   {
> >   	u32 cc_bits  = opcode >> 28;
> > @@ -76,6 +77,7 @@ static unsigned int aarch32_check_condition(u32 opcode, u32 psr)
> >   	}
> >   	return ARM_OPCODE_CONDTEST_UNCOND;
> >   }
> > +#endif
> Could we mark this as '__maybe_unused' or 'inline' instead? I think that's
> preferable to the ifdeferry.

sure, i will use __maybe_unused in v2.

Thanks,

Ren.

> Thanks,
> Mark.
>
> >   
> >   #ifdef CONFIG_SWP_EMULATION
> >   /*
> > --
> > 2.17.1
> .