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Message-ID: <f6fc1fa8bf4decf97d76900a64fe0bc2bf25576d.camel@mengyan1223.wang>
Subject: Re: [PATCH V4 19/22] LoongArch: Add VDSO and VSYSCALL support
From:   Xi Ruoyao <xry111@mengyan1223.wang>
To:     Huacai Chen <chenhuacai@loongson.cn>,
        Arnd Bergmann <arnd@arndb.de>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Airlie <airlied@linux.ie>,
        Jonathan Corbet <corbet@lwn.net>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     linux-arch@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, Xuefeng Li <lixuefeng@loongson.cn>,
        Yanteng Si <siyanteng@loongson.cn>,
        Huacai Chen <chenhuacai@gmail.com>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>
Date:   Thu, 30 Sep 2021 23:43:41 +0800
In-Reply-To: <20210927064300.624279-20-chenhuacai@loongson.cn>
References: <20210927064300.624279-1-chenhuacai@loongson.cn>
         <20210927064300.624279-20-chenhuacai@loongson.cn>
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On Mon, 2021-09-27 at 14:42 +0800, Huacai Chen wrote:
> diff --git a/arch/loongarch/vdso/gen_vdso_offsets.sh
> b/arch/loongarch/vdso/gen_vdso_offsets.sh
> new file mode 100755
> index 000000000000..7da255fea213
> --- /dev/null
> +++ b/arch/loongarch/vdso/gen_vdso_offsets.sh
> @@ -0,0 +1,14 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +
> +#
> +# Derived from RISC-V and ARM64:
> +# Author: Will Deacon <will.deacon@arm.com>
> +#
> +# Match symbols in the DSO that look like VDSO_*; produce a header
> file
> +# of constant offsets into the shared object.
> +#
> +
> +LC_ALL=C

I'm wondering whether this line is really useful... There is no "export"
here so the variable won't be passed to the environment of the sed
command below.

> +sed -n -e 's/^00*/0/' -e \
> +'s/^\([0-9a-fA-F]*\) . VDSO_\([a-zA-Z0-9_]*\)$/\#define
> vdso_offset_\2\t0x\1/p'