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Date:   Thu, 7 Sep 2023 09:49:12 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Puranjay Mohan <puranjay12@gmail.com>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>,
        Yonghong Song <yonghong.song@linux.dev>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Shubham Bansal <illusionist.neo@gmail.com>,
        Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>,
        bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH bpf-next v2 5/8] arm32, bpf: add support for 32-bit
 signed division
Message-ID: <ZPmOiF9UsPf8FN5V@shell.armlinux.org.uk>
References: <20230906183320.1959008-1-puranjay12@gmail.com>
 <20230906183320.1959008-6-puranjay12@gmail.com>
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On Wed, Sep 06, 2023 at 06:33:17PM +0000, Puranjay Mohan wrote:
> The cpuv4 added a new BPF_SDIV instruction that does signed division.
> The encoding is similar to BPF_DIV but BPF_SDIV sets offset=1.
> 
> ARM32 already supports 32-bit BPF_DIV which can be easily extended to
> support BPF_SDIV as ARM32 has the SDIV instruction. When the CPU is not
> ARM-v7, we implement that SDIV/SMOD with the function call similar to
> the implementation of DIV/MOD.
> 
> Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Thanks, this is a lot more clear!

-- 
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