Date:   Sun, 21 Nov 2021 23:37:22 +0200
From:   Lasse Collin <lasse.collin@tukaani.org>
To:     Jubin Zhong <zhongjubin@huawei.com>
Cc:     <akpm@linux-foundation.org>, <wangfangpeng1@huawei.com>,
        <liaohua4@huawei.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] kbuild: Enable armthumb BCJ filter for Thumb-2
 kernel
Message-ID: <20211121233722.708131a8@kaneli>
In-Reply-To: <1637379771-39449-1-git-send-email-zhongjubin@huawei.com>
References: <1637379771-39449-1-git-send-email-zhongjubin@huawei.com>
MIME-Version: 1.0
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On 2021-11-20 Jubin Zhong wrote:
> xz_wrap.sh use $SRCARCH to detect the BCJ filter. However, assigning
> arm BCJ filter to Thumb-2 kernel is not optimal. In my case, about 5%
> decrease of image size is observed with armthumb BCJ filter:
> 
> Test results:
>   hardware:      QEMU emulator version 3.1.0
>   config:        vexpress_defconfig with THUMB2_KERNEL & KERNEL_XZ on
>   arm BCJ:       4029808
>   armthumb BCJ:  3827280
> 
> Choose armthumb BCJ filter for Thumb-2 kernel to make smaller images.
> 
> Signed-off-by: Jubin Zhong <zhongjubin@huawei.com>

I still didn't test it but it looks good to me.

Acked-by: Lasse Collin <lasse.collin@tukaani.org>

-- 
Lasse Collin