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From: yunhui cui <cuiyunhui@bytedance.com>
Date: Mon, 25 Mar 2024 11:59:43 +0800
Message-ID: <CAEEQ3w=mXXTwxph+_ttBLQhvNb66bq9b6Wo-Ka35qpp+3iq2JQ@mail.gmail.com>
Subject: Re: [External] Re: [PATCH] riscv: Improve sbi_ecall() code generation
 by reordering arguments
To: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Qingfang Deng <dqfext@gmail.com>, aou@eecs.berkeley.edu, linux-kernel@vger.kernel.org, 
	linux-riscv@lists.infradead.org, palmer@dabbelt.com, paul.walmsley@sifive.com, 
	samuel.holland@sifive.com
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Hi Alex,

On Mon, Mar 25, 2024 at 2:20=E2=80=AFAM Alexandre Ghiti <alexghiti@rivosinc=
com> wrote:
>
> Hi Qingfang,
>
> On Sat, Mar 23, 2024 at 7:26=E2=80=AFAM Qingfang Deng <dqfext@gmail.com> =
wrote:
> >
> > Hi Alexandre,
> >
> > You can simply make sbi_ecall `__always_inline`, so the C function call
> > overhead can be fully avoided.
>
> I understand your point, though I don't think we need to mark
> sbi_ecall() as inline, it's not in any hot path so it's not worth it.
> This patch simply gets rid of a really useless overhead, but it does
> not visibly accelerate anything.
>
> I hope it makes sense,
>
> Thanks,
>
> Alex
>

The compiler will have inline size restrictions, so I agree with the
modification of this patch instead of inline.
Please refer to:
https://github.com/gcc-mirror/gcc/blob/master/gcc/common.opt,
"finline-limit-"

So=EF=BC=9A
Reviewed-by: Yunhui Cui <cuiyunhui@bytedance.com>

Thanks,
Yunhui