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Message-ID: <28a90ac0-dc8f-f0dd-74d8-d2884e2cbd30@huawei.com>
Date:   Wed, 23 Nov 2022 10:06:03 +0800
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Subject: Re: [PATCH] arm64: armv8_deprecated: fix unused-function error
To:     Mark Rutland <mark.rutland@arm.com>
CC:     <catalin.marinas@arm.com>, <will@kernel.org>,
        <yusongping@huawei.com>, <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
References: <20221122032010.202956-1-renzhijie2@huawei.com>
 <Y3z9dEkMdCeWAWq0@FVFF77S0Q05N.cambridge.arm.com>
From:   Ren Zhijie <renzhijie2@huawei.com>
In-Reply-To: <Y3z9dEkMdCeWAWq0@FVFF77S0Q05N.cambridge.arm.com>
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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@huawei.com>
>> ---
>>   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
>>
> .